1 /*
   2  * Copyright (c) 1997, 2015, Oracle and/or its affiliates. All rights reserved.
   3  * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
   4  *
   5  * This code is free software; you can redistribute it and/or modify it
   6  * under the terms of the GNU General Public License version 2 only, as
   7  * published by the Free Software Foundation.  Oracle designates this
   8  * particular file as subject to the "Classpath" exception as provided
   9  * by Oracle in the LICENSE file that accompanied this code.
  10  *
  11  * This code is distributed in the hope that it will be useful, but WITHOUT
  12  * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
  13  * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
  14  * version 2 for more details (a copy is included in the LICENSE file that
  15  * accompanied this code).
  16  *
  17  * You should have received a copy of the GNU General Public License version
  18  * 2 along with this work; if not, write to the Free Software Foundation,
  19  * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
  20  *
  21  * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
  22  * or visit www.oracle.com if you need additional information or have any
  23  * questions.
  24  */
  25 
  26 package javax.swing.plaf.basic;
  27 
  28 import javax.swing.*;
  29 import javax.swing.event.*;
  30 import java.awt.*;
  31 import java.awt.event.*;
  32 import java.awt.datatransfer.*;
  33 import java.beans.*;
  34 import static java.lang.Boolean.TRUE;
  35 import java.util.Enumeration;
  36 import java.util.Hashtable;
  37 import java.util.ArrayList;
  38 import java.util.Collections;
  39 import java.util.Comparator;
  40 import javax.swing.plaf.ComponentUI;
  41 import javax.swing.plaf.UIResource;
  42 import javax.swing.plaf.TreeUI;
  43 import javax.swing.tree.*;
  44 import javax.swing.text.Position;
  45 import javax.swing.plaf.basic.DragRecognitionSupport.BeforeDrag;
  46 import sun.awt.AWTAccessor;
  47 import sun.swing.SwingUtilities2;
  48 
  49 import sun.swing.DefaultLookup;
  50 import sun.swing.UIAction;
  51 
  52 /**
  53  * The basic L&F for a hierarchical data structure.
  54  *
  55  * @author Scott Violet
  56  * @author Shannon Hickey (drag and drop)
  57  */
  58 
  59 public class BasicTreeUI extends TreeUI
  60 {
  61     private static final StringBuilder BASELINE_COMPONENT_KEY =
  62         new StringBuilder("Tree.baselineComponent");
  63 
  64     // Old actions forward to an instance of this.
  65     private static final Actions SHARED_ACTION = new Actions();
  66 
  67     /**
  68      * The collapsed icon.
  69      */
  70     protected transient Icon        collapsedIcon;
  71     /**
  72      * The expanded icon.
  73      */
  74     protected transient Icon        expandedIcon;
  75 
  76     /**
  77       * Color used to draw hash marks.  If <code>null</code> no hash marks
  78       * will be drawn.
  79       */
  80     private Color hashColor;
  81 
  82     /** Distance between left margin and where vertical dashes will be
  83       * drawn. */
  84     protected int               leftChildIndent;
  85     /** Distance to add to leftChildIndent to determine where cell
  86       * contents will be drawn. */
  87     protected int               rightChildIndent;
  88     /** Total distance that will be indented.  The sum of leftChildIndent
  89       * and rightChildIndent. */
  90     protected int               totalChildIndent;
  91 
  92     /** Minimum preferred size. */
  93     protected Dimension         preferredMinSize;
  94 
  95     /** Index of the row that was last selected. */
  96     protected int               lastSelectedRow;
  97 
  98     /** Component that we're going to be drawing into. */
  99     protected JTree             tree;
 100 
 101     /** Renderer that is being used to do the actual cell drawing. */
 102     protected transient TreeCellRenderer   currentCellRenderer;
 103 
 104     /** Set to true if the renderer that is currently in the tree was
 105      * created by this instance. */
 106     protected boolean           createdRenderer;
 107 
 108     /** Editor for the tree. */
 109     protected transient TreeCellEditor     cellEditor;
 110 
 111     /** Set to true if editor that is currently in the tree was
 112      * created by this instance. */
 113     protected boolean           createdCellEditor;
 114 
 115     /** Set to false when editing and shouldSelectCell() returns true meaning
 116       * the node should be selected before editing, used in completeEditing. */
 117     protected boolean           stopEditingInCompleteEditing;
 118 
 119     /** Used to paint the TreeCellRenderer. */
 120     protected CellRendererPane  rendererPane;
 121 
 122     /** Size needed to completely display all the nodes. */
 123     protected Dimension         preferredSize;
 124 
 125     /** Is the preferredSize valid? */
 126     protected boolean           validCachedPreferredSize;
 127 
 128     /** Object responsible for handling sizing and expanded issues. */
 129     // WARNING: Be careful with the bounds held by treeState. They are
 130     // always in terms of left-to-right. They get mapped to right-to-left
 131     // by the various methods of this class.
 132     protected AbstractLayoutCache  treeState;
 133 
 134 
 135     /** Used for minimizing the drawing of vertical lines. */
 136     protected Hashtable<TreePath,Boolean> drawingCache;
 137 
 138     /** True if doing optimizations for a largeModel. Subclasses that
 139      * don't support this may wish to override createLayoutCache to not
 140      * return a FixedHeightLayoutCache instance. */
 141     protected boolean           largeModel;
 142 
 143     /** Reponsible for telling the TreeState the size needed for a node. */
 144     protected AbstractLayoutCache.NodeDimensions     nodeDimensions;
 145 
 146     /** Used to determine what to display. */
 147     protected TreeModel         treeModel;
 148 
 149     /** Model maintaining the selection. */
 150     protected TreeSelectionModel treeSelectionModel;
 151 
 152     /** How much the depth should be offset to properly calculate
 153      * x locations. This is based on whether or not the root is visible,
 154      * and if the root handles are visible. */
 155     protected int               depthOffset;
 156 
 157     // Following 4 ivars are only valid when editing.
 158 
 159     /** When editing, this will be the Component that is doing the actual
 160       * editing. */
 161     protected Component         editingComponent;
 162 
 163     /** Path that is being edited. */
 164     protected TreePath          editingPath;
 165 
 166     /** Row that is being edited. Should only be referenced if
 167      * editingComponent is not null. */
 168     protected int               editingRow;
 169 
 170     /** Set to true if the editor has a different size than the renderer. */
 171     protected boolean           editorHasDifferentSize;
 172 
 173     /** Row correspondin to lead path. */
 174     private int                 leadRow;
 175     /** If true, the property change event for LEAD_SELECTION_PATH_PROPERTY,
 176      * or ANCHOR_SELECTION_PATH_PROPERTY will not generate a repaint. */
 177     private boolean             ignoreLAChange;
 178 
 179     /** Indicates the orientation. */
 180     private boolean             leftToRight;
 181 
 182     // Cached listeners
 183     private PropertyChangeListener propertyChangeListener;
 184     private PropertyChangeListener selectionModelPropertyChangeListener;
 185     private MouseListener mouseListener;
 186     private FocusListener focusListener;
 187     private KeyListener keyListener;
 188     /** Used for large models, listens for moved/resized events and
 189      * updates the validCachedPreferredSize bit accordingly. */
 190     private ComponentListener   componentListener;
 191     /** Listens for CellEditor events. */
 192     private CellEditorListener  cellEditorListener;
 193     /** Updates the display when the selection changes. */
 194     private TreeSelectionListener treeSelectionListener;
 195     /** Is responsible for updating the display based on model events. */
 196     private TreeModelListener treeModelListener;
 197     /** Updates the treestate as the nodes expand. */
 198     private TreeExpansionListener treeExpansionListener;
 199 
 200     /** UI property indicating whether to paint lines */
 201     private boolean paintLines = true;
 202 
 203     /** UI property for painting dashed lines */
 204     private boolean lineTypeDashed;
 205 
 206     /**
 207      * The time factor to treate the series of typed alphanumeric key
 208      * as prefix for first letter navigation.
 209      */
 210     private long timeFactor = 1000L;
 211 
 212     private Handler handler;
 213 
 214     /**
 215      * A temporary variable for communication between startEditingOnRelease
 216      * and startEditing.
 217      */
 218     private MouseEvent releaseEvent;
 219 
 220     /**
 221      * Constructs a new instance of {@code BasicTreeUI}.
 222      *
 223      * @param x a component
 224      * @return a new instance of {@code BasicTreeUI}
 225      */
 226     public static ComponentUI createUI(JComponent x) {
 227         return new BasicTreeUI();
 228     }
 229 
 230 
 231     static void loadActionMap(LazyActionMap map) {
 232         map.put(new Actions(Actions.SELECT_PREVIOUS));
 233         map.put(new Actions(Actions.SELECT_PREVIOUS_CHANGE_LEAD));
 234         map.put(new Actions(Actions.SELECT_PREVIOUS_EXTEND_SELECTION));
 235 
 236         map.put(new Actions(Actions.SELECT_NEXT));
 237         map.put(new Actions(Actions.SELECT_NEXT_CHANGE_LEAD));
 238         map.put(new Actions(Actions.SELECT_NEXT_EXTEND_SELECTION));
 239 
 240         map.put(new Actions(Actions.SELECT_CHILD));
 241         map.put(new Actions(Actions.SELECT_CHILD_CHANGE_LEAD));
 242 
 243         map.put(new Actions(Actions.SELECT_PARENT));
 244         map.put(new Actions(Actions.SELECT_PARENT_CHANGE_LEAD));
 245 
 246         map.put(new Actions(Actions.SCROLL_UP_CHANGE_SELECTION));
 247         map.put(new Actions(Actions.SCROLL_UP_CHANGE_LEAD));
 248         map.put(new Actions(Actions.SCROLL_UP_EXTEND_SELECTION));
 249 
 250         map.put(new Actions(Actions.SCROLL_DOWN_CHANGE_SELECTION));
 251         map.put(new Actions(Actions.SCROLL_DOWN_EXTEND_SELECTION));
 252         map.put(new Actions(Actions.SCROLL_DOWN_CHANGE_LEAD));
 253 
 254         map.put(new Actions(Actions.SELECT_FIRST));
 255         map.put(new Actions(Actions.SELECT_FIRST_CHANGE_LEAD));
 256         map.put(new Actions(Actions.SELECT_FIRST_EXTEND_SELECTION));
 257 
 258         map.put(new Actions(Actions.SELECT_LAST));
 259         map.put(new Actions(Actions.SELECT_LAST_CHANGE_LEAD));
 260         map.put(new Actions(Actions.SELECT_LAST_EXTEND_SELECTION));
 261 
 262         map.put(new Actions(Actions.TOGGLE));
 263 
 264         map.put(new Actions(Actions.CANCEL_EDITING));
 265 
 266         map.put(new Actions(Actions.START_EDITING));
 267 
 268         map.put(new Actions(Actions.SELECT_ALL));
 269 
 270         map.put(new Actions(Actions.CLEAR_SELECTION));
 271 
 272         map.put(new Actions(Actions.SCROLL_LEFT));
 273         map.put(new Actions(Actions.SCROLL_RIGHT));
 274 
 275         map.put(new Actions(Actions.SCROLL_LEFT_EXTEND_SELECTION));
 276         map.put(new Actions(Actions.SCROLL_RIGHT_EXTEND_SELECTION));
 277 
 278         map.put(new Actions(Actions.SCROLL_RIGHT_CHANGE_LEAD));
 279         map.put(new Actions(Actions.SCROLL_LEFT_CHANGE_LEAD));
 280 
 281         map.put(new Actions(Actions.EXPAND));
 282         map.put(new Actions(Actions.COLLAPSE));
 283         map.put(new Actions(Actions.MOVE_SELECTION_TO_PARENT));
 284 
 285         map.put(new Actions(Actions.ADD_TO_SELECTION));
 286         map.put(new Actions(Actions.TOGGLE_AND_ANCHOR));
 287         map.put(new Actions(Actions.EXTEND_TO));
 288         map.put(new Actions(Actions.MOVE_SELECTION_TO));
 289 
 290         map.put(TransferHandler.getCutAction());
 291         map.put(TransferHandler.getCopyAction());
 292         map.put(TransferHandler.getPasteAction());
 293     }
 294 
 295     /**
 296      * Constructs a new instance of {@code BasicTreeUI}.
 297      */
 298     public BasicTreeUI() {
 299         super();
 300     }
 301 
 302     /**
 303      * Returns the hash color.
 304      *
 305      * @return the hash color
 306      */
 307     protected Color getHashColor() {
 308         return hashColor;
 309     }
 310 
 311     /**
 312      * Sets the hash color.
 313      *
 314      * @param color the hash color
 315      */
 316     protected void setHashColor(Color color) {
 317         hashColor = color;
 318     }
 319 
 320     /**
 321      * Sets the left child indent.
 322      *
 323      * @param newAmount the left child indent
 324      */
 325     public void setLeftChildIndent(int newAmount) {
 326         leftChildIndent = newAmount;
 327         totalChildIndent = leftChildIndent + rightChildIndent;
 328         if(treeState != null)
 329             treeState.invalidateSizes();
 330         updateSize();
 331     }
 332 
 333     /**
 334      * Returns the left child indent.
 335      *
 336      * @return the left child indent
 337      */
 338     public int getLeftChildIndent() {
 339         return leftChildIndent;
 340     }
 341 
 342     /**
 343      * Sets the right child indent.
 344      *
 345      * @param newAmount the right child indent
 346      */
 347     public void setRightChildIndent(int newAmount) {
 348         rightChildIndent = newAmount;
 349         totalChildIndent = leftChildIndent + rightChildIndent;
 350         if(treeState != null)
 351             treeState.invalidateSizes();
 352         updateSize();
 353     }
 354 
 355     /**
 356      * Returns the right child indent.
 357      *
 358      * @return the right child indent
 359      */
 360     public int getRightChildIndent() {
 361         return rightChildIndent;
 362     }
 363 
 364     /**
 365      * Sets the expanded icon.
 366      *
 367      * @param newG the expanded icon
 368      */
 369     public void setExpandedIcon(Icon newG) {
 370         expandedIcon = newG;
 371     }
 372 
 373     /**
 374      * Returns the expanded icon.
 375      *
 376      * @return the expanded icon
 377      */
 378     public Icon getExpandedIcon() {
 379         return expandedIcon;
 380     }
 381 
 382     /**
 383      * Sets the collapsed icon.
 384      *
 385      * @param newG the collapsed icon
 386      */
 387     public void setCollapsedIcon(Icon newG) {
 388         collapsedIcon = newG;
 389     }
 390 
 391     /**
 392      * Returns the collapsed icon.
 393      *
 394      * @return the collapsed icon
 395      */
 396     public Icon getCollapsedIcon() {
 397         return collapsedIcon;
 398     }
 399 
 400     //
 401     // Methods for configuring the behavior of the tree. None of them
 402     // push the value to the JTree instance. You should really only
 403     // call these methods on the JTree.
 404     //
 405 
 406     /**
 407      * Updates the componentListener, if necessary.
 408      *
 409      * @param largeModel the new value
 410      */
 411     protected void setLargeModel(boolean largeModel) {
 412         if(getRowHeight() < 1)
 413             largeModel = false;
 414         if(this.largeModel != largeModel) {
 415             completeEditing();
 416             this.largeModel = largeModel;
 417             treeState = createLayoutCache();
 418             configureLayoutCache();
 419             updateLayoutCacheExpandedNodesIfNecessary();
 420             updateSize();
 421         }
 422     }
 423 
 424     /**
 425      * Returns {@code true} if large model is set.
 426      *
 427      * @return {@code true} if large model is set
 428      */
 429     protected boolean isLargeModel() {
 430         return largeModel;
 431     }
 432 
 433     /**
 434      * Sets the row height, this is forwarded to the treeState.
 435      *
 436      * @param rowHeight the row height
 437      */
 438     protected void setRowHeight(int rowHeight) {
 439         completeEditing();
 440         if(treeState != null) {
 441             setLargeModel(tree.isLargeModel());
 442             treeState.setRowHeight(rowHeight);
 443             updateSize();
 444         }
 445     }
 446 
 447     /**
 448      * Returns the row height.
 449      *
 450      * @return the row height
 451      */
 452     protected int getRowHeight() {
 453         return (tree == null) ? -1 : tree.getRowHeight();
 454     }
 455 
 456     /**
 457      * Sets the {@code TreeCellRenderer} to {@code tcr}. This invokes
 458      * {@code updateRenderer}.
 459      *
 460      * @param tcr the new value
 461      */
 462     protected void setCellRenderer(TreeCellRenderer tcr) {
 463         completeEditing();
 464         updateRenderer();
 465         if(treeState != null) {
 466             treeState.invalidateSizes();
 467             updateSize();
 468         }
 469     }
 470 
 471     /**
 472      * Return {@code currentCellRenderer}, which will either be the trees
 473      * renderer, or {@code defaultCellRenderer}, which ever wasn't null.
 474      *
 475      * @return an instance of {@code TreeCellRenderer}
 476      */
 477     protected TreeCellRenderer getCellRenderer() {
 478         return currentCellRenderer;
 479     }
 480 
 481     /**
 482      * Sets the {@code TreeModel}.
 483      *
 484      * @param model the new value
 485      */
 486     protected void setModel(TreeModel model) {
 487         completeEditing();
 488         if(treeModel != null && treeModelListener != null)
 489             treeModel.removeTreeModelListener(treeModelListener);
 490         treeModel = model;
 491         if(treeModel != null) {
 492             if(treeModelListener != null)
 493                 treeModel.addTreeModelListener(treeModelListener);
 494         }
 495         if(treeState != null) {
 496             treeState.setModel(model);
 497             updateLayoutCacheExpandedNodesIfNecessary();
 498             updateSize();
 499         }
 500     }
 501 
 502     /**
 503      * Returns the tree model.
 504      *
 505      * @return the tree model
 506      */
 507     protected TreeModel getModel() {
 508         return treeModel;
 509     }
 510 
 511     /**
 512      * Sets the root to being visible.
 513      *
 514      * @param newValue the new value
 515      */
 516     protected void setRootVisible(boolean newValue) {
 517         completeEditing();
 518         updateDepthOffset();
 519         if(treeState != null) {
 520             treeState.setRootVisible(newValue);
 521             treeState.invalidateSizes();
 522             updateSize();
 523         }
 524     }
 525 
 526     /**
 527      * Returns {@code true} if the tree root is visible.
 528      *
 529      * @return {@code true} if the tree root is visible
 530      */
 531     protected boolean isRootVisible() {
 532         return (tree != null) ? tree.isRootVisible() : false;
 533     }
 534 
 535     /**
 536      * Determines whether the node handles are to be displayed.
 537      *
 538      * @param newValue the new value
 539      */
 540     protected void setShowsRootHandles(boolean newValue) {
 541         completeEditing();
 542         updateDepthOffset();
 543         if(treeState != null) {
 544             treeState.invalidateSizes();
 545             updateSize();
 546         }
 547     }
 548 
 549     /**
 550      * Returns {@code true} if the root handles are to be displayed.
 551      *
 552      * @return {@code true} if the root handles are to be displayed
 553      */
 554     protected boolean getShowsRootHandles() {
 555         return (tree != null) ? tree.getShowsRootHandles() : false;
 556     }
 557 
 558     /**
 559      * Sets the cell editor.
 560      *
 561      * @param editor the new cell editor
 562      */
 563     protected void setCellEditor(TreeCellEditor editor) {
 564         updateCellEditor();
 565     }
 566 
 567     /**
 568      * Returns an instance of {@code TreeCellEditor}.
 569      *
 570      * @return an instance of {@code TreeCellEditor}
 571      */
 572     protected TreeCellEditor getCellEditor() {
 573         return (tree != null) ? tree.getCellEditor() : null;
 574     }
 575 
 576     /**
 577      * Configures the receiver to allow, or not allow, editing.
 578      *
 579      * @param newValue the new value
 580      */
 581     protected void setEditable(boolean newValue) {
 582         updateCellEditor();
 583     }
 584 
 585     /**
 586      * Returns {@code true} if the tree is editable.
 587      *
 588      * @return {@code true} if the tree is editable
 589      */
 590     protected boolean isEditable() {
 591         return (tree != null) ? tree.isEditable() : false;
 592     }
 593 
 594     /**
 595      * Resets the selection model. The appropriate listener are installed
 596      * on the model.
 597      *
 598      * @param newLSM new selection model
 599      */
 600     protected void setSelectionModel(TreeSelectionModel newLSM) {
 601         completeEditing();
 602         if(selectionModelPropertyChangeListener != null &&
 603            treeSelectionModel != null)
 604             treeSelectionModel.removePropertyChangeListener
 605                               (selectionModelPropertyChangeListener);
 606         if(treeSelectionListener != null && treeSelectionModel != null)
 607             treeSelectionModel.removeTreeSelectionListener
 608                                (treeSelectionListener);
 609         treeSelectionModel = newLSM;
 610         if(treeSelectionModel != null) {
 611             if(selectionModelPropertyChangeListener != null)
 612                 treeSelectionModel.addPropertyChangeListener
 613                               (selectionModelPropertyChangeListener);
 614             if(treeSelectionListener != null)
 615                 treeSelectionModel.addTreeSelectionListener
 616                                    (treeSelectionListener);
 617             if(treeState != null)
 618                 treeState.setSelectionModel(treeSelectionModel);
 619         }
 620         else if(treeState != null)
 621             treeState.setSelectionModel(null);
 622         if(tree != null)
 623             tree.repaint();
 624     }
 625 
 626     /**
 627      * Returns the tree selection model.
 628      *
 629      * @return the tree selection model
 630      */
 631     protected TreeSelectionModel getSelectionModel() {
 632         return treeSelectionModel;
 633     }
 634 
 635     //
 636     // TreeUI methods
 637     //
 638 
 639     /**
 640       * Returns the Rectangle enclosing the label portion that the
 641       * last item in path will be drawn into.  Will return null if
 642       * any component in path is currently valid.
 643       */
 644     public Rectangle getPathBounds(JTree tree, TreePath path) {
 645         if(tree != null && treeState != null) {
 646             return getPathBounds(path, tree.getInsets(), new Rectangle());
 647         }
 648         return null;
 649     }
 650 
 651     private Rectangle getPathBounds(TreePath path, Insets insets,
 652                                     Rectangle bounds) {
 653         bounds = treeState.getBounds(path, bounds);
 654         if (bounds != null) {
 655             if (leftToRight) {
 656                 bounds.x += insets.left;
 657             } else {
 658                 bounds.x = tree.getWidth() - (bounds.x + bounds.width) -
 659                         insets.right;
 660             }
 661             bounds.y += insets.top;
 662         }
 663         return bounds;
 664     }
 665 
 666     /**
 667       * Returns the path for passed in row.  If row is not visible
 668       * null is returned.
 669       */
 670     public TreePath getPathForRow(JTree tree, int row) {
 671         return (treeState != null) ? treeState.getPathForRow(row) : null;
 672     }
 673 
 674     /**
 675       * Returns the row that the last item identified in path is visible
 676       * at.  Will return -1 if any of the elements in path are not
 677       * currently visible.
 678       */
 679     public int getRowForPath(JTree tree, TreePath path) {
 680         return (treeState != null) ? treeState.getRowForPath(path) : -1;
 681     }
 682 
 683     /**
 684       * Returns the number of rows that are being displayed.
 685       */
 686     public int getRowCount(JTree tree) {
 687         return (treeState != null) ? treeState.getRowCount() : 0;
 688     }
 689 
 690     /**
 691       * Returns the path to the node that is closest to x,y.  If
 692       * there is nothing currently visible this will return null, otherwise
 693       * it'll always return a valid path.  If you need to test if the
 694       * returned object is exactly at x, y you should get the bounds for
 695       * the returned path and test x, y against that.
 696       */
 697     public TreePath getClosestPathForLocation(JTree tree, int x, int y) {
 698         if(tree != null && treeState != null) {
 699             // TreeState doesn't care about the x location, hence it isn't
 700             // adjusted
 701             y -= tree.getInsets().top;
 702             return treeState.getPathClosestTo(x, y);
 703         }
 704         return null;
 705     }
 706 
 707     /**
 708       * Returns true if the tree is being edited.  The item that is being
 709       * edited can be returned by getEditingPath().
 710       */
 711     public boolean isEditing(JTree tree) {
 712         return (editingComponent != null);
 713     }
 714 
 715     /**
 716       * Stops the current editing session.  This has no effect if the
 717       * tree isn't being edited.  Returns true if the editor allows the
 718       * editing session to stop.
 719       */
 720     public boolean stopEditing(JTree tree) {
 721         if(editingComponent != null && cellEditor.stopCellEditing()) {
 722             completeEditing(false, false, true);
 723             return true;
 724         }
 725         return false;
 726     }
 727 
 728     /**
 729       * Cancels the current editing session.
 730       */
 731     public void cancelEditing(JTree tree) {
 732         if(editingComponent != null) {
 733             completeEditing(false, true, false);
 734         }
 735     }
 736 
 737     /**
 738       * Selects the last item in path and tries to edit it.  Editing will
 739       * fail if the CellEditor won't allow it for the selected item.
 740       */
 741     public void startEditingAtPath(JTree tree, TreePath path) {
 742         tree.scrollPathToVisible(path);
 743         if(path != null && tree.isVisible(path))
 744             startEditing(path, null);
 745     }
 746 
 747     /**
 748      * Returns the path to the element that is being edited.
 749      */
 750     public TreePath getEditingPath(JTree tree) {
 751         return editingPath;
 752     }
 753 
 754     //
 755     // Install methods
 756     //
 757 
 758     public void installUI(JComponent c) {
 759         if ( c == null ) {
 760             throw new NullPointerException( "null component passed to BasicTreeUI.installUI()" );
 761         }
 762 
 763         tree = (JTree)c;
 764 
 765         prepareForUIInstall();
 766 
 767         // Boilerplate install block
 768         installDefaults();
 769         installKeyboardActions();
 770         installComponents();
 771         installListeners();
 772 
 773         completeUIInstall();
 774     }
 775 
 776     /**
 777      * Invoked after the {@code tree} instance variable has been
 778      * set, but before any defaults/listeners have been installed.
 779      */
 780     protected void prepareForUIInstall() {
 781         drawingCache = new Hashtable<TreePath,Boolean>(7);
 782 
 783         // Data member initializations
 784         leftToRight = BasicGraphicsUtils.isLeftToRight(tree);
 785         stopEditingInCompleteEditing = true;
 786         lastSelectedRow = -1;
 787         leadRow = -1;
 788         preferredSize = new Dimension();
 789 
 790         largeModel = tree.isLargeModel();
 791         if(getRowHeight() <= 0)
 792             largeModel = false;
 793         setModel(tree.getModel());
 794     }
 795 
 796     /**
 797      * Invoked from installUI after all the defaults/listeners have been
 798      * installed.
 799      */
 800     protected void completeUIInstall() {
 801         // Custom install code
 802 
 803         this.setShowsRootHandles(tree.getShowsRootHandles());
 804 
 805         updateRenderer();
 806 
 807         updateDepthOffset();
 808 
 809         setSelectionModel(tree.getSelectionModel());
 810 
 811         // Create, if necessary, the TreeState instance.
 812         treeState = createLayoutCache();
 813         configureLayoutCache();
 814 
 815         updateSize();
 816     }
 817 
 818     /**
 819      * Installs default properties.
 820      */
 821     protected void installDefaults() {
 822         if(tree.getBackground() == null ||
 823            tree.getBackground() instanceof UIResource) {
 824             tree.setBackground(UIManager.getColor("Tree.background"));
 825         }
 826         if(getHashColor() == null || getHashColor() instanceof UIResource) {
 827             setHashColor(UIManager.getColor("Tree.hash"));
 828         }
 829         if (tree.getFont() == null || tree.getFont() instanceof UIResource)
 830             tree.setFont( UIManager.getFont("Tree.font") );
 831         // JTree's original row height is 16.  To correctly display the
 832         // contents on Linux we should have set it to 18, Windows 19 and
 833         // Solaris 20.  As these values vary so much it's too hard to
 834         // be backward compatable and try to update the row height, we're
 835         // therefor NOT going to adjust the row height based on font.  If the
 836         // developer changes the font, it's there responsibility to update
 837         // the row height.
 838 
 839         setExpandedIcon( (Icon)UIManager.get( "Tree.expandedIcon" ) );
 840         setCollapsedIcon( (Icon)UIManager.get( "Tree.collapsedIcon" ) );
 841 
 842         setLeftChildIndent(((Integer)UIManager.get("Tree.leftChildIndent")).
 843                            intValue());
 844         setRightChildIndent(((Integer)UIManager.get("Tree.rightChildIndent")).
 845                            intValue());
 846 
 847         LookAndFeel.installProperty(tree, "rowHeight",
 848                                     UIManager.get("Tree.rowHeight"));
 849 
 850         largeModel = (tree.isLargeModel() && tree.getRowHeight() > 0);
 851 
 852         Object scrollsOnExpand = UIManager.get("Tree.scrollsOnExpand");
 853         if (scrollsOnExpand != null) {
 854             LookAndFeel.installProperty(tree, "scrollsOnExpand", scrollsOnExpand);
 855         }
 856 
 857         paintLines = UIManager.getBoolean("Tree.paintLines");
 858         lineTypeDashed = UIManager.getBoolean("Tree.lineTypeDashed");
 859 
 860         Long l = (Long)UIManager.get("Tree.timeFactor");
 861         timeFactor = (l!=null) ? l.longValue() : 1000L;
 862 
 863         Object showsRootHandles = UIManager.get("Tree.showsRootHandles");
 864         if (showsRootHandles != null) {
 865             LookAndFeel.installProperty(tree,
 866                     JTree.SHOWS_ROOT_HANDLES_PROPERTY, showsRootHandles);
 867         }
 868     }
 869 
 870     /**
 871      * Registers listeners.
 872      */
 873     protected void installListeners() {
 874         if ( (propertyChangeListener = createPropertyChangeListener())
 875              != null ) {
 876             tree.addPropertyChangeListener(propertyChangeListener);
 877         }
 878         if ( (mouseListener = createMouseListener()) != null ) {
 879             tree.addMouseListener(mouseListener);
 880             if (mouseListener instanceof MouseMotionListener) {
 881                 tree.addMouseMotionListener((MouseMotionListener)mouseListener);
 882             }
 883         }
 884         if ((focusListener = createFocusListener()) != null ) {
 885             tree.addFocusListener(focusListener);
 886         }
 887         if ((keyListener = createKeyListener()) != null) {
 888             tree.addKeyListener(keyListener);
 889         }
 890         if((treeExpansionListener = createTreeExpansionListener()) != null) {
 891             tree.addTreeExpansionListener(treeExpansionListener);
 892         }
 893         if((treeModelListener = createTreeModelListener()) != null &&
 894            treeModel != null) {
 895             treeModel.addTreeModelListener(treeModelListener);
 896         }
 897         if((selectionModelPropertyChangeListener =
 898             createSelectionModelPropertyChangeListener()) != null &&
 899            treeSelectionModel != null) {
 900             treeSelectionModel.addPropertyChangeListener
 901                 (selectionModelPropertyChangeListener);
 902         }
 903         if((treeSelectionListener = createTreeSelectionListener()) != null &&
 904            treeSelectionModel != null) {
 905             treeSelectionModel.addTreeSelectionListener(treeSelectionListener);
 906         }
 907 
 908         TransferHandler th = tree.getTransferHandler();
 909         if (th == null || th instanceof UIResource) {
 910             tree.setTransferHandler(defaultTransferHandler);
 911             // default TransferHandler doesn't support drop
 912             // so we don't want drop handling
 913             if (tree.getDropTarget() instanceof UIResource) {
 914                 tree.setDropTarget(null);
 915             }
 916         }
 917 
 918         LookAndFeel.installProperty(tree, "opaque", Boolean.TRUE);
 919     }
 920 
 921     /**
 922      * Registers keyboard actions.
 923      */
 924     protected void installKeyboardActions() {
 925         InputMap km = getInputMap(JComponent.
 926                                   WHEN_ANCESTOR_OF_FOCUSED_COMPONENT);
 927 
 928         SwingUtilities.replaceUIInputMap(tree, JComponent.
 929                                          WHEN_ANCESTOR_OF_FOCUSED_COMPONENT,
 930                                          km);
 931         km = getInputMap(JComponent.WHEN_FOCUSED);
 932         SwingUtilities.replaceUIInputMap(tree, JComponent.WHEN_FOCUSED, km);
 933 
 934         LazyActionMap.installLazyActionMap(tree, BasicTreeUI.class,
 935                                            "Tree.actionMap");
 936     }
 937 
 938     InputMap getInputMap(int condition) {
 939         if (condition == JComponent.WHEN_ANCESTOR_OF_FOCUSED_COMPONENT) {
 940             return (InputMap)DefaultLookup.get(tree, this,
 941                                                "Tree.ancestorInputMap");
 942         }
 943         else if (condition == JComponent.WHEN_FOCUSED) {
 944             InputMap keyMap = (InputMap)DefaultLookup.get(tree, this,
 945                                                       "Tree.focusInputMap");
 946             InputMap rtlKeyMap;
 947 
 948             if (tree.getComponentOrientation().isLeftToRight() ||
 949                   ((rtlKeyMap = (InputMap)DefaultLookup.get(tree, this,
 950                   "Tree.focusInputMap.RightToLeft")) == null)) {
 951                 return keyMap;
 952             } else {
 953                 rtlKeyMap.setParent(keyMap);
 954                 return rtlKeyMap;
 955             }
 956         }
 957         return null;
 958     }
 959 
 960     /**
 961      * Intalls the subcomponents of the tree, which is the renderer pane.
 962      */
 963     protected void installComponents() {
 964         if ((rendererPane = createCellRendererPane()) != null) {
 965             tree.add( rendererPane );
 966         }
 967     }
 968 
 969     //
 970     // Create methods.
 971     //
 972 
 973     /**
 974      * Creates an instance of {@code NodeDimensions} that is able to determine
 975      * the size of a given node in the tree.
 976      *
 977      * @return an instance of {@code NodeDimensions}
 978      */
 979     protected AbstractLayoutCache.NodeDimensions createNodeDimensions() {
 980         return new NodeDimensionsHandler();
 981     }
 982 
 983     /**
 984      * Creates a listener that is responsible that updates the UI based on
 985      * how the tree changes.
 986      *
 987      * @return an instance of the {@code PropertyChangeListener}
 988      */
 989     protected PropertyChangeListener createPropertyChangeListener() {
 990         return getHandler();
 991     }
 992 
 993     private Handler getHandler() {
 994         if (handler == null) {
 995             handler = new Handler();
 996         }
 997         return handler;
 998     }
 999 
1000     /**
1001      * Creates the listener responsible for updating the selection based on
1002      * mouse events.
1003      *
1004      * @return an instance of the {@code MouseListener}
1005      */
1006     protected MouseListener createMouseListener() {
1007         return getHandler();
1008     }
1009 
1010     /**
1011      * Creates a listener that is responsible for updating the display
1012      * when focus is lost/gained.
1013      *
1014      * @return an instance of the {@code FocusListener}
1015      */
1016     protected FocusListener createFocusListener() {
1017         return getHandler();
1018     }
1019 
1020     /**
1021      * Creates the listener responsible for getting key events from
1022      * the tree.
1023      *
1024      * @return an instance of the {@code KeyListener}
1025      */
1026     protected KeyListener createKeyListener() {
1027         return getHandler();
1028     }
1029 
1030     /**
1031      * Creates the listener responsible for getting property change
1032      * events from the selection model.
1033      *
1034      * @return an instance of the {@code PropertyChangeListener}
1035      */
1036     protected PropertyChangeListener createSelectionModelPropertyChangeListener() {
1037         return getHandler();
1038     }
1039 
1040     /**
1041      * Creates the listener that updates the display based on selection change
1042      * methods.
1043      *
1044      * @return an instance of the {@code TreeSelectionListener}
1045      */
1046     protected TreeSelectionListener createTreeSelectionListener() {
1047         return getHandler();
1048     }
1049 
1050     /**
1051      * Creates a listener to handle events from the current editor.
1052      *
1053      * @return an instance of the {@code CellEditorListener}
1054      */
1055     protected CellEditorListener createCellEditorListener() {
1056         return getHandler();
1057     }
1058 
1059     /**
1060      * Creates and returns a new ComponentHandler. This is used for
1061      * the large model to mark the validCachedPreferredSize as invalid
1062      * when the component moves.
1063      *
1064      * @return an instance of the {@code ComponentListener}
1065      */
1066     protected ComponentListener createComponentListener() {
1067         return new ComponentHandler();
1068     }
1069 
1070     /**
1071      * Creates and returns the object responsible for updating the treestate
1072      * when nodes expanded state changes.
1073      *
1074      * @return an instance of the {@code TreeExpansionListener}
1075      */
1076     protected TreeExpansionListener createTreeExpansionListener() {
1077         return getHandler();
1078     }
1079 
1080     /**
1081      * Creates the object responsible for managing what is expanded, as
1082      * well as the size of nodes.
1083      *
1084      * @return the object responsible for managing what is expanded
1085      */
1086     protected AbstractLayoutCache createLayoutCache() {
1087         if(isLargeModel() && getRowHeight() > 0) {
1088             return new FixedHeightLayoutCache();
1089         }
1090         return new VariableHeightLayoutCache();
1091     }
1092 
1093     /**
1094      * Returns the renderer pane that renderer components are placed in.
1095      *
1096      * @return an instance of the {@code CellRendererPane}
1097      */
1098     protected CellRendererPane createCellRendererPane() {
1099         return new CellRendererPane();
1100     }
1101 
1102     /**
1103      * Creates a default cell editor.
1104      *
1105      * @return a default cell editor
1106      */
1107     protected TreeCellEditor createDefaultCellEditor() {
1108         if(currentCellRenderer != null &&
1109            (currentCellRenderer instanceof DefaultTreeCellRenderer)) {
1110             DefaultTreeCellEditor editor = new DefaultTreeCellEditor
1111                         (tree, (DefaultTreeCellRenderer)currentCellRenderer);
1112 
1113             return editor;
1114         }
1115         return new DefaultTreeCellEditor(tree, null);
1116     }
1117 
1118     /**
1119      * Returns the default cell renderer that is used to do the
1120      * stamping of each node.
1121      *
1122      * @return an instance of {@code TreeCellRenderer}
1123      */
1124     protected TreeCellRenderer createDefaultCellRenderer() {
1125         return new DefaultTreeCellRenderer();
1126     }
1127 
1128     /**
1129      * Returns a listener that can update the tree when the model changes.
1130      *
1131      * @return an instance of the {@code TreeModelListener}.
1132      */
1133     protected TreeModelListener createTreeModelListener() {
1134         return getHandler();
1135     }
1136 
1137     //
1138     // Uninstall methods
1139     //
1140 
1141     public void uninstallUI(JComponent c) {
1142         completeEditing();
1143 
1144         prepareForUIUninstall();
1145 
1146         uninstallDefaults();
1147         uninstallListeners();
1148         uninstallKeyboardActions();
1149         uninstallComponents();
1150 
1151         completeUIUninstall();
1152     }
1153 
1154     /**
1155      * Invoked before unstallation of UI.
1156      */
1157     protected void prepareForUIUninstall() {
1158     }
1159 
1160     /**
1161      * Uninstalls UI.
1162      */
1163     protected void completeUIUninstall() {
1164         if(createdRenderer) {
1165             tree.setCellRenderer(null);
1166         }
1167         if(createdCellEditor) {
1168             tree.setCellEditor(null);
1169         }
1170         cellEditor = null;
1171         currentCellRenderer = null;
1172         rendererPane = null;
1173         componentListener = null;
1174         propertyChangeListener = null;
1175         mouseListener = null;
1176         focusListener = null;
1177         keyListener = null;
1178         setSelectionModel(null);
1179         treeState = null;
1180         drawingCache = null;
1181         selectionModelPropertyChangeListener = null;
1182         tree = null;
1183         treeModel = null;
1184         treeSelectionModel = null;
1185         treeSelectionListener = null;
1186         treeExpansionListener = null;
1187     }
1188 
1189     /**
1190      * Uninstalls default properties.
1191      */
1192     protected void uninstallDefaults() {
1193         if (tree.getTransferHandler() instanceof UIResource) {
1194             tree.setTransferHandler(null);
1195         }
1196     }
1197 
1198     /**
1199      * Unregisters listeners.
1200      */
1201     protected void uninstallListeners() {
1202         if(componentListener != null) {
1203             tree.removeComponentListener(componentListener);
1204         }
1205         if (propertyChangeListener != null) {
1206             tree.removePropertyChangeListener(propertyChangeListener);
1207         }
1208         if (mouseListener != null) {
1209             tree.removeMouseListener(mouseListener);
1210             if (mouseListener instanceof MouseMotionListener) {
1211                 tree.removeMouseMotionListener((MouseMotionListener)mouseListener);
1212             }
1213         }
1214         if (focusListener != null) {
1215             tree.removeFocusListener(focusListener);
1216         }
1217         if (keyListener != null) {
1218             tree.removeKeyListener(keyListener);
1219         }
1220         if(treeExpansionListener != null) {
1221             tree.removeTreeExpansionListener(treeExpansionListener);
1222         }
1223         if(treeModel != null && treeModelListener != null) {
1224             treeModel.removeTreeModelListener(treeModelListener);
1225         }
1226         if(selectionModelPropertyChangeListener != null &&
1227            treeSelectionModel != null) {
1228             treeSelectionModel.removePropertyChangeListener
1229                 (selectionModelPropertyChangeListener);
1230         }
1231         if(treeSelectionListener != null && treeSelectionModel != null) {
1232             treeSelectionModel.removeTreeSelectionListener
1233                                (treeSelectionListener);
1234         }
1235         handler = null;
1236     }
1237 
1238     /**
1239      * Unregisters keyboard actions.
1240      */
1241     protected void uninstallKeyboardActions() {
1242         SwingUtilities.replaceUIActionMap(tree, null);
1243         SwingUtilities.replaceUIInputMap(tree, JComponent.
1244                                          WHEN_ANCESTOR_OF_FOCUSED_COMPONENT,
1245                                          null);
1246         SwingUtilities.replaceUIInputMap(tree, JComponent.WHEN_FOCUSED, null);
1247     }
1248 
1249     /**
1250      * Uninstalls the renderer pane.
1251      */
1252     protected void uninstallComponents() {
1253         if(rendererPane != null) {
1254             tree.remove(rendererPane);
1255         }
1256     }
1257 
1258     /**
1259      * Recomputes the right margin, and invalidates any tree states
1260      */
1261     private void redoTheLayout() {
1262         if (treeState != null) {
1263             treeState.invalidateSizes();
1264         }
1265     }
1266 
1267     /**
1268      * Returns the baseline.
1269      *
1270      * @throws NullPointerException {@inheritDoc}
1271      * @throws IllegalArgumentException {@inheritDoc}
1272      * @see javax.swing.JComponent#getBaseline(int, int)
1273      * @since 1.6
1274      */
1275     public int getBaseline(JComponent c, int width, int height) {
1276         super.getBaseline(c, width, height);
1277         UIDefaults lafDefaults = UIManager.getLookAndFeelDefaults();
1278         Component renderer = (Component)lafDefaults.get(
1279                 BASELINE_COMPONENT_KEY);
1280         if (renderer == null) {
1281             TreeCellRenderer tcr = createDefaultCellRenderer();
1282             renderer = tcr.getTreeCellRendererComponent(
1283                     tree, "a", false, false, false, -1, false);
1284             lafDefaults.put(BASELINE_COMPONENT_KEY, renderer);
1285         }
1286         int rowHeight = tree.getRowHeight();
1287         int baseline;
1288         if (rowHeight > 0) {
1289             baseline = renderer.getBaseline(Integer.MAX_VALUE, rowHeight);
1290         }
1291         else {
1292             Dimension pref = renderer.getPreferredSize();
1293             baseline = renderer.getBaseline(pref.width, pref.height);
1294         }
1295         return baseline + tree.getInsets().top;
1296     }
1297 
1298     /**
1299      * Returns an enum indicating how the baseline of the component
1300      * changes as the size changes.
1301      *
1302      * @throws NullPointerException {@inheritDoc}
1303      * @see javax.swing.JComponent#getBaseline(int, int)
1304      * @since 1.6
1305      */
1306     public Component.BaselineResizeBehavior getBaselineResizeBehavior(
1307             JComponent c) {
1308         super.getBaselineResizeBehavior(c);
1309         return Component.BaselineResizeBehavior.CONSTANT_ASCENT;
1310     }
1311 
1312     //
1313     // Painting routines.
1314     //
1315 
1316     public void paint(Graphics g, JComponent c) {
1317         if (tree != c) {
1318             throw new InternalError("incorrect component");
1319         }
1320 
1321         // Should never happen if installed for a UI
1322         if(treeState == null) {
1323             return;
1324         }
1325 
1326         Rectangle        paintBounds = g.getClipBounds();
1327         Insets           insets = tree.getInsets();
1328         TreePath         initialPath = getClosestPathForLocation
1329                                        (tree, 0, paintBounds.y);
1330         Enumeration<?>   paintingEnumerator = treeState.getVisiblePathsFrom
1331                                               (initialPath);
1332         int              row = treeState.getRowForPath(initialPath);
1333         int              endY = paintBounds.y + paintBounds.height;
1334 
1335         drawingCache.clear();
1336 
1337         if(initialPath != null && paintingEnumerator != null) {
1338             TreePath   parentPath = initialPath;
1339 
1340             // Draw the lines, knobs, and rows
1341 
1342             // Find each parent and have them draw a line to their last child
1343             parentPath = parentPath.getParentPath();
1344             while(parentPath != null) {
1345                 paintVerticalPartOfLeg(g, paintBounds, insets, parentPath);
1346                 drawingCache.put(parentPath, Boolean.TRUE);
1347                 parentPath = parentPath.getParentPath();
1348             }
1349 
1350             boolean         done = false;
1351             // Information for the node being rendered.
1352             boolean         isExpanded;
1353             boolean         hasBeenExpanded;
1354             boolean         isLeaf;
1355             Rectangle       boundsBuffer = new Rectangle();
1356             Rectangle       bounds;
1357             TreePath        path;
1358             boolean         rootVisible = isRootVisible();
1359 
1360             while(!done && paintingEnumerator.hasMoreElements()) {
1361                 path = (TreePath)paintingEnumerator.nextElement();
1362                 if(path != null) {
1363                     isLeaf = treeModel.isLeaf(path.getLastPathComponent());
1364                     if(isLeaf)
1365                         isExpanded = hasBeenExpanded = false;
1366                     else {
1367                         isExpanded = treeState.getExpandedState(path);
1368                         hasBeenExpanded = tree.hasBeenExpanded(path);
1369                     }
1370                     bounds = getPathBounds(path, insets, boundsBuffer);
1371                     if(bounds == null)
1372                         // This will only happen if the model changes out
1373                         // from under us (usually in another thread).
1374                         // Swing isn't multithreaded, but I'll put this
1375                         // check in anyway.
1376                         return;
1377                     // See if the vertical line to the parent has been drawn.
1378                     parentPath = path.getParentPath();
1379                     if(parentPath != null) {
1380                         if(drawingCache.get(parentPath) == null) {
1381                             paintVerticalPartOfLeg(g, paintBounds,
1382                                                    insets, parentPath);
1383                             drawingCache.put(parentPath, Boolean.TRUE);
1384                         }
1385                         paintHorizontalPartOfLeg(g, paintBounds, insets,
1386                                                  bounds, path, row,
1387                                                  isExpanded,
1388                                                  hasBeenExpanded, isLeaf);
1389                     }
1390                     else if(rootVisible && row == 0) {
1391                         paintHorizontalPartOfLeg(g, paintBounds, insets,
1392                                                  bounds, path, row,
1393                                                  isExpanded,
1394                                                  hasBeenExpanded, isLeaf);
1395                     }
1396                     if(shouldPaintExpandControl(path, row, isExpanded,
1397                                                 hasBeenExpanded, isLeaf)) {
1398                         paintExpandControl(g, paintBounds, insets, bounds,
1399                                            path, row, isExpanded,
1400                                            hasBeenExpanded, isLeaf);
1401                     }
1402                     paintRow(g, paintBounds, insets, bounds, path,
1403                                  row, isExpanded, hasBeenExpanded, isLeaf);
1404                     if((bounds.y + bounds.height) >= endY)
1405                         done = true;
1406                 }
1407                 else {
1408                     done = true;
1409                 }
1410                 row++;
1411             }
1412         }
1413 
1414         paintDropLine(g);
1415 
1416         // Empty out the renderer pane, allowing renderers to be gc'ed.
1417         rendererPane.removeAll();
1418 
1419         drawingCache.clear();
1420     }
1421 
1422     /**
1423      * Tells if a {@code DropLocation} should be indicated by a line between
1424      * nodes. This is meant for {@code javax.swing.DropMode.INSERT} and
1425      * {@code javax.swing.DropMode.ON_OR_INSERT} drop modes.
1426      *
1427      * @param loc a {@code DropLocation}
1428      * @return {@code true} if the drop location should be shown as a line
1429      * @since 1.7
1430      */
1431     protected boolean isDropLine(JTree.DropLocation loc) {
1432         return loc != null && loc.getPath() != null && loc.getChildIndex() != -1;
1433     }
1434 
1435     /**
1436      * Paints the drop line.
1437      *
1438      * @param g {@code Graphics} object to draw on
1439      * @since 1.7
1440      */
1441     protected void paintDropLine(Graphics g) {
1442         JTree.DropLocation loc = tree.getDropLocation();
1443         if (!isDropLine(loc)) {
1444             return;
1445         }
1446 
1447         Color c = UIManager.getColor("Tree.dropLineColor");
1448         if (c != null) {
1449             g.setColor(c);
1450             Rectangle rect = getDropLineRect(loc);
1451             g.fillRect(rect.x, rect.y, rect.width, rect.height);
1452         }
1453     }
1454 
1455     /**
1456      * Returns a unbounding box for the drop line.
1457      *
1458      * @param loc a {@code DropLocation}
1459      * @return bounding box for the drop line
1460      * @since 1.7
1461      */
1462     protected Rectangle getDropLineRect(JTree.DropLocation loc) {
1463         Rectangle rect;
1464         TreePath path = loc.getPath();
1465         int index = loc.getChildIndex();
1466         boolean ltr = leftToRight;
1467 
1468         Insets insets = tree.getInsets();
1469 
1470         if (tree.getRowCount() == 0) {
1471             rect = new Rectangle(insets.left,
1472                                  insets.top,
1473                                  tree.getWidth() - insets.left - insets.right,
1474                                  0);
1475         } else {
1476             TreeModel model = getModel();
1477             Object root = model.getRoot();
1478 
1479             if (path.getLastPathComponent() == root
1480                     && index >= model.getChildCount(root)) {
1481 
1482                 rect = tree.getRowBounds(tree.getRowCount() - 1);
1483                 rect.y = rect.y + rect.height;
1484                 Rectangle xRect;
1485 
1486                 if (!tree.isRootVisible()) {
1487                     xRect = tree.getRowBounds(0);
1488                 } else if (model.getChildCount(root) == 0){
1489                     xRect = tree.getRowBounds(0);
1490                     xRect.x += totalChildIndent;
1491                     xRect.width -= totalChildIndent + totalChildIndent;
1492                 } else {
1493                     TreePath lastChildPath = path.pathByAddingChild(
1494                         model.getChild(root, model.getChildCount(root) - 1));
1495                     xRect = tree.getPathBounds(lastChildPath);
1496                 }
1497 
1498                 rect.x = xRect.x;
1499                 rect.width = xRect.width;
1500             } else {
1501                 if (index >= model.getChildCount(path.getLastPathComponent())) {
1502                     rect = tree.getPathBounds(path.pathByAddingChild(
1503                             model.getChild(path.getLastPathComponent(),
1504                                     index - 1)));
1505                     rect.y = rect.y + rect.height;
1506                 } else {
1507                     rect = tree.getPathBounds(path.pathByAddingChild(
1508                             model.getChild(path.getLastPathComponent(),
1509                                     index)));
1510                 }
1511             }
1512         }
1513 
1514         if (rect.y != 0) {
1515             rect.y--;
1516         }
1517 
1518         if (!ltr) {
1519             rect.x = rect.x + rect.width - 100;
1520         }
1521 
1522         rect.width = 100;
1523         rect.height = 2;
1524 
1525         return rect;
1526     }
1527 
1528     /**
1529      * Paints the horizontal part of the leg. The receiver should
1530      * NOT modify {@code clipBounds}, or {@code insets}.<p>
1531      * NOTE: {@code parentRow} can be -1 if the root is not visible.
1532      *
1533      * @param g a graphics context
1534      * @param clipBounds a clipped rectangle
1535      * @param insets insets
1536      * @param bounds a bounding rectangle
1537      * @param path a tree path
1538      * @param row a row
1539      * @param isExpanded {@code true} if the path is expanded
1540      * @param hasBeenExpanded {@code true} if the path has been expanded
1541      * @param isLeaf {@code true} if the path is leaf
1542      */
1543     protected void paintHorizontalPartOfLeg(Graphics g, Rectangle clipBounds,
1544                                             Insets insets, Rectangle bounds,
1545                                             TreePath path, int row,
1546                                             boolean isExpanded,
1547                                             boolean hasBeenExpanded, boolean
1548                                             isLeaf) {
1549         if (!paintLines) {
1550             return;
1551         }
1552 
1553         // Don't paint the legs for the root'ish node if the
1554         int depth = path.getPathCount() - 1;
1555         if((depth == 0 || (depth == 1 && !isRootVisible())) &&
1556            !getShowsRootHandles()) {
1557             return;
1558         }
1559 
1560         int clipLeft = clipBounds.x;
1561         int clipRight = clipBounds.x + clipBounds.width;
1562         int clipTop = clipBounds.y;
1563         int clipBottom = clipBounds.y + clipBounds.height;
1564         int lineY = bounds.y + bounds.height / 2;
1565 
1566         if (leftToRight) {
1567             int leftX = bounds.x - getRightChildIndent();
1568             int nodeX = bounds.x - getHorizontalLegBuffer();
1569 
1570             if(lineY >= clipTop
1571                     && lineY < clipBottom
1572                     && nodeX >= clipLeft
1573                     && leftX < clipRight
1574                     && leftX < nodeX) {
1575 
1576                 g.setColor(getHashColor());
1577                 paintHorizontalLine(g, tree, lineY, leftX, nodeX - 1);
1578             }
1579         } else {
1580             int nodeX = bounds.x + bounds.width + getHorizontalLegBuffer();
1581             int rightX = bounds.x + bounds.width + getRightChildIndent();
1582 
1583             if(lineY >= clipTop
1584                     && lineY < clipBottom
1585                     && rightX >= clipLeft
1586                     && nodeX < clipRight
1587                     && nodeX < rightX) {
1588 
1589                 g.setColor(getHashColor());
1590                 paintHorizontalLine(g, tree, lineY, nodeX, rightX - 1);
1591             }
1592         }
1593     }
1594 
1595     /**
1596      * Paints the vertical part of the leg. The receiver should
1597      * NOT modify {@code clipBounds}, {@code insets}.
1598      *
1599      * @param g a graphics context
1600      * @param clipBounds a clipped rectangle
1601      * @param insets insets
1602      * @param path a tree path
1603      */
1604     protected void paintVerticalPartOfLeg(Graphics g, Rectangle clipBounds,
1605                                           Insets insets, TreePath path) {
1606         if (!paintLines) {
1607             return;
1608         }
1609 
1610         int depth = path.getPathCount() - 1;
1611         if (depth == 0 && !getShowsRootHandles() && !isRootVisible()) {
1612             return;
1613         }
1614         int lineX = getRowX(-1, depth + 1);
1615         if (leftToRight) {
1616             lineX = lineX - getRightChildIndent() + insets.left;
1617         }
1618         else {
1619             lineX = tree.getWidth() - lineX - insets.right +
1620                     getRightChildIndent() - 1;
1621         }
1622         int clipLeft = clipBounds.x;
1623         int clipRight = clipBounds.x + (clipBounds.width - 1);
1624 
1625         if (lineX >= clipLeft && lineX <= clipRight) {
1626             int clipTop = clipBounds.y;
1627             int clipBottom = clipBounds.y + clipBounds.height;
1628             Rectangle parentBounds = getPathBounds(tree, path);
1629             Rectangle lastChildBounds = getPathBounds(tree,
1630                                                      getLastChildPath(path));
1631 
1632             if(lastChildBounds == null)
1633                 // This shouldn't happen, but if the model is modified
1634                 // in another thread it is possible for this to happen.
1635                 // Swing isn't multithreaded, but I'll add this check in
1636                 // anyway.
1637                 return;
1638 
1639             int       top;
1640 
1641             if(parentBounds == null) {
1642                 top = Math.max(insets.top + getVerticalLegBuffer(),
1643                                clipTop);
1644             }
1645             else
1646                 top = Math.max(parentBounds.y + parentBounds.height +
1647                                getVerticalLegBuffer(), clipTop);
1648             if(depth == 0 && !isRootVisible()) {
1649                 TreeModel      model = getModel();
1650 
1651                 if(model != null) {
1652                     Object        root = model.getRoot();
1653 
1654                     if(model.getChildCount(root) > 0) {
1655                         parentBounds = getPathBounds(tree, path.
1656                                   pathByAddingChild(model.getChild(root, 0)));
1657                         if(parentBounds != null)
1658                             top = Math.max(insets.top + getVerticalLegBuffer(),
1659                                            parentBounds.y +
1660                                            parentBounds.height / 2);
1661                     }
1662                 }
1663             }
1664 
1665             int bottom = Math.min(lastChildBounds.y +
1666                                   (lastChildBounds.height / 2), clipBottom);
1667 
1668             if (top <= bottom) {
1669                 g.setColor(getHashColor());
1670                 paintVerticalLine(g, tree, lineX, top, bottom);
1671             }
1672         }
1673     }
1674 
1675     /**
1676      * Paints the expand (toggle) part of a row. The receiver should
1677      * NOT modify {@code clipBounds}, or {@code insets}.
1678      *
1679      * @param g a graphics context
1680      * @param clipBounds a clipped rectangle
1681      * @param insets insets
1682      * @param bounds a bounding rectangle
1683      * @param path a tree path
1684      * @param row a row
1685      * @param isExpanded {@code true} if the path is expanded
1686      * @param hasBeenExpanded {@code true} if the path has been expanded
1687      * @param isLeaf {@code true} if the row is leaf
1688      */
1689     protected void paintExpandControl(Graphics g,
1690                                       Rectangle clipBounds, Insets insets,
1691                                       Rectangle bounds, TreePath path,
1692                                       int row, boolean isExpanded,
1693                                       boolean hasBeenExpanded,
1694                                       boolean isLeaf) {
1695         Object       value = path.getLastPathComponent();
1696 
1697         // Draw icons if not a leaf and either hasn't been loaded,
1698         // or the model child count is > 0.
1699         if (!isLeaf && (!hasBeenExpanded ||
1700                         treeModel.getChildCount(value) > 0)) {
1701             int middleXOfKnob;
1702             if (leftToRight) {
1703                 middleXOfKnob = bounds.x - getRightChildIndent() + 1;
1704             } else {
1705                 middleXOfKnob = bounds.x + bounds.width + getRightChildIndent() - 1;
1706             }
1707             int middleYOfKnob = bounds.y + (bounds.height / 2);
1708 
1709             if (isExpanded) {
1710                 Icon expandedIcon = getExpandedIcon();
1711                 if(expandedIcon != null)
1712                   drawCentered(tree, g, expandedIcon, middleXOfKnob,
1713                                middleYOfKnob );
1714             }
1715             else {
1716                 Icon collapsedIcon = getCollapsedIcon();
1717                 if(collapsedIcon != null)
1718                   drawCentered(tree, g, collapsedIcon, middleXOfKnob,
1719                                middleYOfKnob);
1720             }
1721         }
1722     }
1723 
1724     /**
1725      * Paints the renderer part of a row. The receiver should
1726      * NOT modify {@code clipBounds}, or {@code insets}.
1727      *
1728      * @param g a graphics context
1729      * @param clipBounds a clipped rectangle
1730      * @param insets insets
1731      * @param bounds a bounding rectangle
1732      * @param path a tree path
1733      * @param row a row
1734      * @param isExpanded {@code true} if the path is expanded
1735      * @param hasBeenExpanded {@code true} if the path has been expanded
1736      * @param isLeaf {@code true} if the path is leaf
1737      */
1738     protected void paintRow(Graphics g, Rectangle clipBounds,
1739                             Insets insets, Rectangle bounds, TreePath path,
1740                             int row, boolean isExpanded,
1741                             boolean hasBeenExpanded, boolean isLeaf) {
1742         // Don't paint the renderer if editing this row.
1743         if(editingComponent != null && editingRow == row)
1744             return;
1745 
1746         int leadIndex;
1747 
1748         if(tree.hasFocus()) {
1749             leadIndex = getLeadSelectionRow();
1750         }
1751         else
1752             leadIndex = -1;
1753 
1754         Component component;
1755 
1756         component = currentCellRenderer.getTreeCellRendererComponent
1757                       (tree, path.getLastPathComponent(),
1758                        tree.isRowSelected(row), isExpanded, isLeaf, row,
1759                        (leadIndex == row));
1760 
1761         rendererPane.paintComponent(g, component, tree, bounds.x, bounds.y,
1762                                     bounds.width, bounds.height, true);
1763     }
1764 
1765     /**
1766      * Returns {@code true} if the expand (toggle) control should be drawn for
1767      * the specified row.
1768      *
1769      * @param path a tree path
1770      * @param row a row
1771      * @param isExpanded {@code true} if the path is expanded
1772      * @param hasBeenExpanded {@code true} if the path has been expanded
1773      * @param isLeaf {@code true} if the row is leaf
1774      * @return {@code true} if the expand (toggle) control should be drawn
1775      *         for the specified row
1776      */
1777     protected boolean shouldPaintExpandControl(TreePath path, int row,
1778                                                boolean isExpanded,
1779                                                boolean hasBeenExpanded,
1780                                                boolean isLeaf) {
1781         if(isLeaf)
1782             return false;
1783 
1784         int              depth = path.getPathCount() - 1;
1785 
1786         if((depth == 0 || (depth == 1 && !isRootVisible())) &&
1787            !getShowsRootHandles())
1788             return false;
1789         return true;
1790     }
1791 
1792     /**
1793      * Paints a vertical line.
1794      *
1795      * @param g a graphics context
1796      * @param c a component
1797      * @param x an X coordinate
1798      * @param top an Y1 coordinate
1799      * @param bottom an Y2 coordinate
1800      */
1801     protected void paintVerticalLine(Graphics g, JComponent c, int x, int top,
1802                                     int bottom) {
1803         if (lineTypeDashed) {
1804             drawDashedVerticalLine(g, x, top, bottom);
1805         } else {
1806             g.drawLine(x, top, x, bottom);
1807         }
1808     }
1809 
1810     /**
1811      * Paints a horizontal line.
1812      *
1813      * @param g a graphics context
1814      * @param c a component
1815      * @param y an Y coordinate
1816      * @param left an X1 coordinate
1817      * @param right an X2 coordinate
1818      */
1819     protected void paintHorizontalLine(Graphics g, JComponent c, int y,
1820                                       int left, int right) {
1821         if (lineTypeDashed) {
1822             drawDashedHorizontalLine(g, y, left, right);
1823         } else {
1824             g.drawLine(left, y, right, y);
1825         }
1826     }
1827 
1828     /**
1829      * The vertical element of legs between nodes starts at the bottom of the
1830      * parent node by default.  This method makes the leg start below that.
1831      *
1832      * @return the vertical leg buffer
1833      */
1834     protected int getVerticalLegBuffer() {
1835         return 0;
1836     }
1837 
1838     /**
1839      * The horizontal element of legs between nodes starts at the
1840      * right of the left-hand side of the child node by default.  This
1841      * method makes the leg end before that.
1842      *
1843      * @return the horizontal leg buffer
1844      */
1845     protected int getHorizontalLegBuffer() {
1846         return 0;
1847     }
1848 
1849     private int findCenteredX(int x, int iconWidth) {
1850         return leftToRight
1851                ? x - (int)Math.ceil(iconWidth / 2.0)
1852                : x - (int)Math.floor(iconWidth / 2.0);
1853     }
1854 
1855     //
1856     // Generic painting methods
1857     //
1858 
1859     /**
1860      * Draws the {@code icon} centered at (x,y).
1861      *
1862      * @param c a component
1863      * @param graphics a graphics context
1864      * @param icon an icon
1865      * @param x an X coordinate
1866      * @param y an Y coordinate
1867      */
1868     protected void drawCentered(Component c, Graphics graphics, Icon icon,
1869                                 int x, int y) {
1870         icon.paintIcon(c, graphics,
1871                       findCenteredX(x, icon.getIconWidth()),
1872                       y - icon.getIconHeight() / 2);
1873     }
1874 
1875     /**
1876      * Draws a horizontal dashed line. It is assumed {@code x1} &lt;= {@code x2}.
1877      * If {@code x1} is greater than {@code x2}, the method draws nothing.
1878      *
1879      * @param g an instance of {@code Graphics}
1880      * @param y an Y coordinate
1881      * @param x1 an X1 coordinate
1882      * @param x2 an X2 coordinate
1883      */
1884     protected void drawDashedHorizontalLine(Graphics g, int y, int x1, int x2) {
1885         // Drawing only even coordinates helps join line segments so they
1886         // appear as one line.  This can be defeated by translating the
1887         // Graphics by an odd amount.
1888         drawDashedLine(g, y, x1, x2, false);
1889     }
1890 
1891     /**
1892      * Draws a vertical dashed line. It is assumed {@code y1} &lt;= {@code y2}.
1893      * If {@code y1} is greater than {@code y2}, the method draws nothing.
1894      *
1895      * @param g an instance of {@code Graphics}
1896      * @param x an X coordinate
1897      * @param y1 an Y1 coordinate
1898      * @param y2 an Y2 coordinate
1899      */
1900     protected void drawDashedVerticalLine(Graphics g, int x, int y1, int y2) {
1901         // Drawing only even coordinates helps join line segments so they
1902         // appear as one line.  This can be defeated by translating the
1903         // Graphics by an odd amount.
1904         drawDashedLine(g, x, y1, y2, true);
1905     }
1906 
1907     private void drawDashedLine(Graphics g, int v, int v1, int v2, boolean isVertical) {
1908         if (v1 >= v2) {
1909             return;
1910         }
1911         v1 += (v1 % 2);
1912         Graphics2D g2d = (Graphics2D) g;
1913         Stroke oldStroke = g2d.getStroke();
1914 
1915         BasicStroke dashedStroke = new BasicStroke(1, BasicStroke.CAP_BUTT,
1916                 BasicStroke.JOIN_ROUND, 0, new float[]{1}, 0);
1917         g2d.setStroke(dashedStroke);
1918         if (isVertical) {
1919             g2d.drawLine(v, v1, v, v2);
1920         } else {
1921             g2d.drawLine(v1, v, v2, v);
1922         }
1923 
1924         g2d.setStroke(oldStroke);
1925     }
1926     //
1927     // Various local methods
1928     //
1929 
1930     /**
1931      * Returns the location, along the x-axis, to render a particular row
1932      * at. The return value does not include any Insets specified on the JTree.
1933      * This does not check for the validity of the row or depth, it is assumed
1934      * to be correct and will not throw an Exception if the row or depth
1935      * doesn't match that of the tree.
1936      *
1937      * @param row Row to return x location for
1938      * @param depth Depth of the row
1939      * @return amount to indent the given row.
1940      * @since 1.5
1941      */
1942     protected int getRowX(int row, int depth) {
1943         return totalChildIndent * (depth + depthOffset);
1944     }
1945 
1946     /**
1947      * Makes all the nodes that are expanded in JTree expanded in LayoutCache.
1948      * This invokes updateExpandedDescendants with the root path.
1949      */
1950     protected void updateLayoutCacheExpandedNodes() {
1951         if(treeModel != null && treeModel.getRoot() != null)
1952             updateExpandedDescendants(new TreePath(treeModel.getRoot()));
1953     }
1954 
1955     private void updateLayoutCacheExpandedNodesIfNecessary() {
1956         if (treeModel != null && treeModel.getRoot() != null) {
1957             TreePath rootPath = new TreePath(treeModel.getRoot());
1958             if (tree.isExpanded(rootPath)) {
1959                 updateLayoutCacheExpandedNodes();
1960             } else {
1961                 treeState.setExpandedState(rootPath, false);
1962             }
1963         }
1964     }
1965 
1966     /**
1967      * Updates the expanded state of all the descendants of {@code path}
1968      * by getting the expanded descendants from the tree and forwarding
1969      * to the tree state.
1970      *
1971      * @param path a tree path
1972      */
1973     protected void updateExpandedDescendants(TreePath path) {
1974         completeEditing();
1975         if(treeState != null) {
1976             treeState.setExpandedState(path, true);
1977 
1978             Enumeration<?> descendants = tree.getExpandedDescendants(path);
1979 
1980             if(descendants != null) {
1981                 while(descendants.hasMoreElements()) {
1982                     path = (TreePath)descendants.nextElement();
1983                     treeState.setExpandedState(path, true);
1984                 }
1985             }
1986             updateLeadSelectionRow();
1987             updateSize();
1988         }
1989     }
1990 
1991     /**
1992      * Returns a path to the last child of {@code parent}.
1993      *
1994      * @param parent a tree path
1995      * @return a path to the last child of {@code parent}
1996      */
1997     protected TreePath getLastChildPath(TreePath parent) {
1998         if(treeModel != null) {
1999             int         childCount = treeModel.getChildCount
2000                 (parent.getLastPathComponent());
2001 
2002             if(childCount > 0)
2003                 return parent.pathByAddingChild(treeModel.getChild
2004                            (parent.getLastPathComponent(), childCount - 1));
2005         }
2006         return null;
2007     }
2008 
2009     /**
2010      * Updates how much each depth should be offset by.
2011      */
2012     protected void updateDepthOffset() {
2013         if(isRootVisible()) {
2014             if(getShowsRootHandles())
2015                 depthOffset = 1;
2016             else
2017                 depthOffset = 0;
2018         }
2019         else if(!getShowsRootHandles())
2020             depthOffset = -1;
2021         else
2022             depthOffset = 0;
2023     }
2024 
2025     /**
2026       * Updates the cellEditor based on the editability of the JTree that
2027       * we're contained in.  If the tree is editable but doesn't have a
2028       * cellEditor, a basic one will be used.
2029       */
2030     protected void updateCellEditor() {
2031         TreeCellEditor        newEditor;
2032 
2033         completeEditing();
2034         if(tree == null)
2035             newEditor = null;
2036         else {
2037             if(tree.isEditable()) {
2038                 newEditor = tree.getCellEditor();
2039                 if(newEditor == null) {
2040                     newEditor = createDefaultCellEditor();
2041                     if(newEditor != null) {
2042                         tree.setCellEditor(newEditor);
2043                         createdCellEditor = true;
2044                     }
2045                 }
2046             }
2047             else
2048                 newEditor = null;
2049         }
2050         if(newEditor != cellEditor) {
2051             if(cellEditor != null && cellEditorListener != null)
2052                 cellEditor.removeCellEditorListener(cellEditorListener);
2053             cellEditor = newEditor;
2054             if(cellEditorListener == null)
2055                 cellEditorListener = createCellEditorListener();
2056             if(newEditor != null && cellEditorListener != null)
2057                 newEditor.addCellEditorListener(cellEditorListener);
2058             createdCellEditor = false;
2059         }
2060     }
2061 
2062     /**
2063       * Messaged from the tree we're in when the renderer has changed.
2064       */
2065     protected void updateRenderer() {
2066         if(tree != null) {
2067             TreeCellRenderer      newCellRenderer;
2068 
2069             newCellRenderer = tree.getCellRenderer();
2070             if(newCellRenderer == null) {
2071                 tree.setCellRenderer(createDefaultCellRenderer());
2072                 createdRenderer = true;
2073             }
2074             else {
2075                 createdRenderer = false;
2076                 currentCellRenderer = newCellRenderer;
2077                 if(createdCellEditor) {
2078                     tree.setCellEditor(null);
2079                 }
2080             }
2081         }
2082         else {
2083             createdRenderer = false;
2084             currentCellRenderer = null;
2085         }
2086         updateCellEditor();
2087     }
2088 
2089     /**
2090      * Resets the TreeState instance based on the tree we're providing the
2091      * look and feel for.
2092      */
2093     protected void configureLayoutCache() {
2094         if(treeState != null && tree != null) {
2095             if(nodeDimensions == null)
2096                 nodeDimensions = createNodeDimensions();
2097             treeState.setNodeDimensions(nodeDimensions);
2098             treeState.setRootVisible(tree.isRootVisible());
2099             treeState.setRowHeight(tree.getRowHeight());
2100             treeState.setSelectionModel(getSelectionModel());
2101             // Only do this if necessary, may loss state if call with
2102             // same model as it currently has.
2103             if(treeState.getModel() != tree.getModel())
2104                 treeState.setModel(tree.getModel());
2105             updateLayoutCacheExpandedNodesIfNecessary();
2106             // Create a listener to update preferred size when bounds
2107             // changes, if necessary.
2108             if(isLargeModel()) {
2109                 if(componentListener == null) {
2110                     componentListener = createComponentListener();
2111                     if(componentListener != null)
2112                         tree.addComponentListener(componentListener);
2113                 }
2114             }
2115             else if(componentListener != null) {
2116                 tree.removeComponentListener(componentListener);
2117                 componentListener = null;
2118             }
2119         }
2120         else if(componentListener != null) {
2121             tree.removeComponentListener(componentListener);
2122             componentListener = null;
2123         }
2124     }
2125 
2126     /**
2127      * Marks the cached size as being invalid, and messages the
2128      * tree with <code>treeDidChange</code>.
2129      */
2130     protected void updateSize() {
2131         validCachedPreferredSize = false;
2132         tree.treeDidChange();
2133     }
2134 
2135     private void updateSize0() {
2136         validCachedPreferredSize = false;
2137         tree.revalidate();
2138     }
2139 
2140     /**
2141      * Updates the <code>preferredSize</code> instance variable,
2142      * which is returned from <code>getPreferredSize()</code>.<p>
2143      * For left to right orientations, the size is determined from the
2144      * current AbstractLayoutCache. For RTL orientations, the preferred size
2145      * becomes the width minus the minimum x position.
2146      */
2147     protected void updateCachedPreferredSize() {
2148         if(treeState != null) {
2149             Insets               i = tree.getInsets();
2150 
2151             if(isLargeModel()) {
2152                 Rectangle            visRect = tree.getVisibleRect();
2153 
2154                 if (visRect.x == 0 && visRect.y == 0 &&
2155                         visRect.width == 0 && visRect.height == 0 &&
2156                         tree.getVisibleRowCount() > 0) {
2157                     // The tree doesn't have a valid bounds yet. Calculate
2158                     // based on visible row count.
2159                     visRect.width = 1;
2160                     visRect.height = tree.getRowHeight() *
2161                             tree.getVisibleRowCount();
2162                 } else {
2163                     visRect.x -= i.left;
2164                     visRect.y -= i.top;
2165                 }
2166                 // we should consider a non-visible area above
2167                 Component component = SwingUtilities.getUnwrappedParent(tree);
2168                 if (component instanceof JViewport) {
2169                     component = component.getParent();
2170                     if (component instanceof JScrollPane) {
2171                         JScrollPane pane = (JScrollPane) component;
2172                         JScrollBar bar = pane.getHorizontalScrollBar();
2173                         if ((bar != null) && bar.isVisible()) {
2174                             int height = bar.getHeight();
2175                             visRect.y -= height;
2176                             visRect.height += height;
2177                         }
2178                     }
2179                 }
2180                 preferredSize.width = treeState.getPreferredWidth(visRect);
2181             }
2182             else {
2183                 preferredSize.width = treeState.getPreferredWidth(null);
2184             }
2185             preferredSize.height = treeState.getPreferredHeight();
2186             preferredSize.width += i.left + i.right;
2187             preferredSize.height += i.top + i.bottom;
2188         }
2189         validCachedPreferredSize = true;
2190     }
2191 
2192     /**
2193      * Messaged from the {@code VisibleTreeNode} after it has been expanded.
2194      *
2195      * @param path a tree path
2196      */
2197     protected void pathWasExpanded(TreePath path) {
2198         if(tree != null) {
2199             tree.fireTreeExpanded(path);
2200         }
2201     }
2202 
2203     /**
2204      * Messaged from the {@code VisibleTreeNode} after it has collapsed.
2205      *
2206      * @param path a tree path
2207      */
2208     protected void pathWasCollapsed(TreePath path) {
2209         if(tree != null) {
2210             tree.fireTreeCollapsed(path);
2211         }
2212     }
2213 
2214     /**
2215      * Ensures that the rows identified by {@code beginRow} through
2216      * {@code endRow} are visible.
2217      *
2218      * @param beginRow the begin row
2219      * @param endRow the end row
2220      */
2221     protected void ensureRowsAreVisible(int beginRow, int endRow) {
2222         if(tree != null && beginRow >= 0 && endRow < getRowCount(tree)) {
2223             boolean scrollVert = DefaultLookup.getBoolean(tree, this,
2224                               "Tree.scrollsHorizontallyAndVertically", false);
2225             if(beginRow == endRow) {
2226                 Rectangle     scrollBounds = getPathBounds(tree, getPathForRow
2227                                                            (tree, beginRow));
2228 
2229                 if(scrollBounds != null) {
2230                     if (!scrollVert) {
2231                         scrollBounds.x = tree.getVisibleRect().x;
2232                         scrollBounds.width = 1;
2233                     }
2234                     tree.scrollRectToVisible(scrollBounds);
2235                 }
2236             }
2237             else {
2238                 Rectangle   beginRect = getPathBounds(tree, getPathForRow
2239                                                       (tree, beginRow));
2240                 if (beginRect != null) {
2241                     Rectangle   visRect = tree.getVisibleRect();
2242                     Rectangle   testRect = beginRect;
2243                     int         beginY = beginRect.y;
2244                     int         maxY = beginY + visRect.height;
2245 
2246                     for(int counter = beginRow + 1; counter <= endRow; counter++) {
2247                             testRect = getPathBounds(tree,
2248                                     getPathForRow(tree, counter));
2249                         if (testRect == null) {
2250                             return;
2251                         }
2252                         if((testRect.y + testRect.height) > maxY)
2253                                 counter = endRow;
2254                             }
2255                         tree.scrollRectToVisible(new Rectangle(visRect.x, beginY, 1,
2256                                                       testRect.y + testRect.height-
2257                                                       beginY));
2258                 }
2259             }
2260         }
2261     }
2262 
2263     /**
2264      * Sets the preferred minimum size.
2265      *
2266      * @param newSize the new preferred size
2267      */
2268     public void setPreferredMinSize(Dimension newSize) {
2269         preferredMinSize = newSize;
2270     }
2271 
2272     /**
2273      * Returns the minimum preferred size.
2274      *
2275      * @return the minimum preferred size
2276      */
2277     public Dimension getPreferredMinSize() {
2278         if(preferredMinSize == null)
2279             return null;
2280         return new Dimension(preferredMinSize);
2281     }
2282 
2283     /**
2284      * Returns the preferred size to properly display the tree,
2285      * this is a cover method for {@code getPreferredSize(c, true)}.
2286      *
2287      * @param c a component
2288      * @return the preferred size to represent the tree in the component
2289      */
2290     public Dimension getPreferredSize(JComponent c) {
2291         return getPreferredSize(c, true);
2292     }
2293 
2294     /**
2295      * Returns the preferred size to represent the tree in
2296      * <I>c</I>.  If <I>checkConsistency</I> is {@code true}
2297      * <b>checkConsistency</b> is messaged first.
2298      *
2299      * @param c a component
2300      * @param checkConsistency if {@code true} consistency is checked
2301      * @return the preferred size to represent the tree in the component
2302      */
2303     public Dimension getPreferredSize(JComponent c,
2304                                       boolean checkConsistency) {
2305         Dimension       pSize = this.getPreferredMinSize();
2306 
2307         if(!validCachedPreferredSize)
2308             updateCachedPreferredSize();
2309         if(tree != null) {
2310             if(pSize != null)
2311                 return new Dimension(Math.max(pSize.width,
2312                                               preferredSize.width),
2313                               Math.max(pSize.height, preferredSize.height));
2314             return new Dimension(preferredSize.width, preferredSize.height);
2315         }
2316         else if(pSize != null)
2317             return pSize;
2318         else
2319             return new Dimension(0, 0);
2320     }
2321 
2322     /**
2323       * Returns the minimum size for this component.  Which will be
2324       * the min preferred size or 0, 0.
2325       */
2326     public Dimension getMinimumSize(JComponent c) {
2327         if(this.getPreferredMinSize() != null)
2328             return this.getPreferredMinSize();
2329         return new Dimension(0, 0);
2330     }
2331 
2332     /**
2333       * Returns the maximum size for this component, which will be the
2334       * preferred size if the instance is currently in a JTree, or 0, 0.
2335       */
2336     public Dimension getMaximumSize(JComponent c) {
2337         if(tree != null)
2338             return getPreferredSize(tree);
2339         if(this.getPreferredMinSize() != null)
2340             return this.getPreferredMinSize();
2341         return new Dimension(0, 0);
2342     }
2343 
2344 
2345     /**
2346      * Messages to stop the editing session. If the UI the receiver
2347      * is providing the look and feel for returns true from
2348      * <code>getInvokesStopCellEditing</code>, stopCellEditing will
2349      * invoked on the current editor. Then completeEditing will
2350      * be messaged with false, true, false to cancel any lingering
2351      * editing.
2352      */
2353     protected void completeEditing() {
2354         /* If should invoke stopCellEditing, try that */
2355         if(tree.getInvokesStopCellEditing() &&
2356            stopEditingInCompleteEditing && editingComponent != null) {
2357             cellEditor.stopCellEditing();
2358         }
2359         /* Invoke cancelCellEditing, this will do nothing if stopCellEditing
2360            was successful. */
2361         completeEditing(false, true, false);
2362     }
2363 
2364     /**
2365      * Stops the editing session. If {@code messageStop} is {@code true} the editor
2366      * is messaged with {@code stopEditing}, if {@code messageCancel}
2367      * is {@code true} the editor is messaged with {@code cancelEditing}.
2368      * If {@code messageTree} is {@code true} the {@code treeModel} is messaged
2369      * with {@code valueForPathChanged}.
2370      *
2371      * @param messageStop message to stop editing
2372      * @param messageCancel message to cancel editing
2373      * @param messageTree message to tree
2374      */
2375     @SuppressWarnings("deprecation")
2376     protected void completeEditing(boolean messageStop,
2377                                    boolean messageCancel,
2378                                    boolean messageTree) {
2379         if(stopEditingInCompleteEditing && editingComponent != null) {
2380             Component             oldComponent = editingComponent;
2381             TreePath              oldPath = editingPath;
2382             TreeCellEditor        oldEditor = cellEditor;
2383             Object                newValue = oldEditor.getCellEditorValue();
2384             Rectangle             editingBounds = getPathBounds(tree,
2385                                                                 editingPath);
2386             boolean               requestFocus = (tree != null &&
2387                                    (tree.hasFocus() || SwingUtilities.
2388                                     findFocusOwner(editingComponent) != null));
2389 
2390             editingComponent = null;
2391             editingPath = null;
2392             if(messageStop)
2393                 oldEditor.stopCellEditing();
2394             else if(messageCancel)
2395                 oldEditor.cancelCellEditing();
2396             tree.remove(oldComponent);
2397             if(editorHasDifferentSize) {
2398                 treeState.invalidatePathBounds(oldPath);
2399                 updateSize();
2400             }
2401             else if (editingBounds != null) {
2402                 editingBounds.x = 0;
2403                 editingBounds.width = tree.getSize().width;
2404                 tree.repaint(editingBounds);
2405             }
2406             if(requestFocus)
2407                 tree.requestFocus();
2408             if(messageTree)
2409                 treeModel.valueForPathChanged(oldPath, newValue);
2410         }
2411     }
2412 
2413     // cover method for startEditing that allows us to pass extra
2414     // information into that method via a class variable
2415     private boolean startEditingOnRelease(TreePath path,
2416                                           MouseEvent event,
2417                                           MouseEvent releaseEvent) {
2418         this.releaseEvent = releaseEvent;
2419         try {
2420             return startEditing(path, event);
2421         } finally {
2422             this.releaseEvent = null;
2423         }
2424     }
2425 
2426     /**
2427      * Will start editing for node if there is a {@code cellEditor} and
2428      * {@code shouldSelectCell} returns {@code true}.<p>
2429      * This assumes that path is valid and visible.
2430      *
2431      * @param path a tree path
2432      * @param event a mouse event
2433      * @return {@code true} if the editing is successful
2434      */
2435     protected boolean startEditing(TreePath path, MouseEvent event) {
2436         if (isEditing(tree) && tree.getInvokesStopCellEditing() &&
2437                                !stopEditing(tree)) {
2438             return false;
2439         }
2440         completeEditing();
2441         if(cellEditor != null && tree.isPathEditable(path)) {
2442             int           row = getRowForPath(tree, path);
2443 
2444             if(cellEditor.isCellEditable(event)) {
2445                 editingComponent = cellEditor.getTreeCellEditorComponent
2446                       (tree, path.getLastPathComponent(),
2447                        tree.isPathSelected(path), tree.isExpanded(path),
2448                        treeModel.isLeaf(path.getLastPathComponent()), row);
2449                 Rectangle           nodeBounds = getPathBounds(tree, path);
2450                 if (nodeBounds == null) {
2451                     return false;
2452                 }
2453 
2454                 editingRow = row;
2455 
2456                 Dimension editorSize = editingComponent.getPreferredSize();
2457 
2458                 // Only allow odd heights if explicitly set.
2459                 if(editorSize.height != nodeBounds.height &&
2460                    getRowHeight() > 0)
2461                     editorSize.height = getRowHeight();
2462 
2463                 if(editorSize.width != nodeBounds.width ||
2464                    editorSize.height != nodeBounds.height) {
2465                     // Editor wants different width or height, invalidate
2466                     // treeState and relayout.
2467                     editorHasDifferentSize = true;
2468                     treeState.invalidatePathBounds(path);
2469                     updateSize();
2470                     // To make sure x/y are updated correctly, fetch
2471                     // the bounds again.
2472                     nodeBounds = getPathBounds(tree, path);
2473                     if (nodeBounds == null) {
2474                         return false;
2475                     }
2476                 }
2477                 else
2478                     editorHasDifferentSize = false;
2479                 tree.add(editingComponent);
2480                 editingComponent.setBounds(nodeBounds.x, nodeBounds.y,
2481                                            nodeBounds.width,
2482                                            nodeBounds.height);
2483                 editingPath = path;
2484                 AWTAccessor.getComponentAccessor().revalidateSynchronously(editingComponent);
2485                 editingComponent.repaint();
2486                 if(cellEditor.shouldSelectCell(event)) {
2487                     stopEditingInCompleteEditing = false;
2488                     tree.setSelectionRow(row);
2489                     stopEditingInCompleteEditing = true;
2490                 }
2491 
2492                 Component focusedComponent = SwingUtilities2.
2493                                  compositeRequestFocus(editingComponent);
2494                 boolean selectAll = true;
2495 
2496                 if(event != null) {
2497                     /* Find the component that will get forwarded all the
2498                        mouse events until mouseReleased. */
2499                     Point          componentPoint = SwingUtilities.convertPoint
2500                         (tree, new Point(event.getX(), event.getY()),
2501                          editingComponent);
2502 
2503                     /* Create an instance of BasicTreeMouseListener to handle
2504                        passing the mouse/motion events to the necessary
2505                        component. */
2506                     // We really want similar behavior to getMouseEventTarget,
2507                     // but it is package private.
2508                     Component activeComponent = SwingUtilities.
2509                                     getDeepestComponentAt(editingComponent,
2510                                        componentPoint.x, componentPoint.y);
2511                     if (activeComponent != null) {
2512                         MouseInputHandler handler =
2513                             new MouseInputHandler(tree, activeComponent,
2514                                                   event, focusedComponent);
2515 
2516                         if (releaseEvent != null) {
2517                             handler.mouseReleased(releaseEvent);
2518                         }
2519 
2520                         selectAll = false;
2521                     }
2522                 }
2523                 if (selectAll && focusedComponent instanceof JTextField) {
2524                     ((JTextField)focusedComponent).selectAll();
2525                 }
2526                 return true;
2527             }
2528             else
2529                 editingComponent = null;
2530         }
2531         return false;
2532     }
2533 
2534     //
2535     // Following are primarily for handling mouse events.
2536     //
2537 
2538     /**
2539      * If the {@code mouseX} and {@code mouseY} are in the
2540      * expand/collapse region of the {@code row}, this will toggle
2541      * the row.
2542      *
2543      * @param path a tree path
2544      * @param mouseX an X coordinate
2545      * @param mouseY an Y coordinate
2546      */
2547     protected void checkForClickInExpandControl(TreePath path,
2548                                                 int mouseX, int mouseY) {
2549       if (isLocationInExpandControl(path, mouseX, mouseY)) {
2550           handleExpandControlClick(path, mouseX, mouseY);
2551         }
2552     }
2553 
2554     /**
2555      * Returns {@code true} if {@code mouseX} and {@code mouseY} fall
2556      * in the area of row that is used to expand/collapse the node and
2557      * the node at {@code row} does not represent a leaf.
2558      *
2559      * @param path a tree path
2560      * @param mouseX an X coordinate
2561      * @param mouseY an Y coordinate
2562      * @return {@code true} if the mouse cursor fall in the area of row that
2563      *         is used to expand/collapse the node and the node is not a leaf.
2564      */
2565     protected boolean isLocationInExpandControl(TreePath path,
2566                                                 int mouseX, int mouseY) {
2567         if(path != null && !treeModel.isLeaf(path.getLastPathComponent())){
2568             int                     boxWidth;
2569             Insets                  i = tree.getInsets();
2570 
2571             if(getExpandedIcon() != null)
2572                 boxWidth = getExpandedIcon().getIconWidth();
2573             else
2574                 boxWidth = 8;
2575 
2576             int boxLeftX = getRowX(tree.getRowForPath(path),
2577                                    path.getPathCount() - 1);
2578 
2579             if (leftToRight) {
2580                 boxLeftX = boxLeftX + i.left - getRightChildIndent() + 1;
2581             } else {
2582                 boxLeftX = tree.getWidth() - boxLeftX - i.right + getRightChildIndent() - 1;
2583             }
2584 
2585             boxLeftX = findCenteredX(boxLeftX, boxWidth);
2586 
2587             return (mouseX >= boxLeftX && mouseX < (boxLeftX + boxWidth));
2588         }
2589         return false;
2590     }
2591 
2592     /**
2593      * Messaged when the user clicks the particular row, this invokes
2594      * {@code toggleExpandState}.
2595      *
2596      * @param path a tree path
2597      * @param mouseX an X coordinate
2598      * @param mouseY an Y coordinate
2599      */
2600     protected void handleExpandControlClick(TreePath path, int mouseX,
2601                                             int mouseY) {
2602         toggleExpandState(path);
2603     }
2604 
2605     /**
2606      * Expands path if it is not expanded, or collapses row if it is expanded.
2607      * If expanding a path and {@code JTree} scrolls on expand,
2608      * {@code ensureRowsAreVisible} is invoked to scroll as many of the children
2609      * to visible as possible (tries to scroll to last visible descendant of path).
2610      *
2611      * @param path a tree path
2612      */
2613     protected void toggleExpandState(TreePath path) {
2614         if(!tree.isExpanded(path)) {
2615             int       row = getRowForPath(tree, path);
2616 
2617             tree.expandPath(path);
2618             updateSize();
2619             if(row != -1) {
2620                 if(tree.getScrollsOnExpand())
2621                     ensureRowsAreVisible(row, row + treeState.
2622                                          getVisibleChildCount(path));
2623                 else
2624                     ensureRowsAreVisible(row, row);
2625             }
2626         }
2627         else {
2628             tree.collapsePath(path);
2629             updateSize();
2630         }
2631     }
2632 
2633     /**
2634      * Returning {@code true} signifies a mouse event on the node should toggle
2635      * the selection of only the row under mouse.
2636      *
2637      * @param event a mouse event
2638      * @return {@code true} if a mouse event on the node should toggle the selection
2639      */
2640     protected boolean isToggleSelectionEvent(MouseEvent event) {
2641         return (SwingUtilities.isLeftMouseButton(event) &&
2642                 BasicGraphicsUtils.isMenuShortcutKeyDown(event));
2643     }
2644 
2645     /**
2646      * Returning {@code true} signifies a mouse event on the node should select
2647      * from the anchor point.
2648      *
2649      * @param event a mouse event
2650      * @return {@code true} if a mouse event on the node should select
2651      *         from the anchor point
2652      */
2653     protected boolean isMultiSelectEvent(MouseEvent event) {
2654         return (SwingUtilities.isLeftMouseButton(event) &&
2655                 event.isShiftDown());
2656     }
2657 
2658     /**
2659      * Returning {@code true} indicates the row under the mouse should be toggled
2660      * based on the event. This is invoked after {@code checkForClickInExpandControl},
2661      * implying the location is not in the expand (toggle) control.
2662      *
2663      * @param event a mouse event
2664      * @return {@code true} if the row under the mouse should be toggled
2665      */
2666     protected boolean isToggleEvent(MouseEvent event) {
2667         if(!SwingUtilities.isLeftMouseButton(event)) {
2668             return false;
2669         }
2670         int           clickCount = tree.getToggleClickCount();
2671 
2672         if(clickCount <= 0) {
2673             return false;
2674         }
2675         return ((event.getClickCount() % clickCount) == 0);
2676     }
2677 
2678     /**
2679      * Messaged to update the selection based on a {@code MouseEvent} over a
2680      * particular row. If the event is a toggle selection event, the
2681      * row is either selected, or deselected. If the event identifies
2682      * a multi selection event, the selection is updated from the
2683      * anchor point. Otherwise the row is selected, and if the event
2684      * specified a toggle event the row is expanded/collapsed.
2685      *
2686      * @param path the selected path
2687      * @param event the mouse event
2688      */
2689     protected void selectPathForEvent(TreePath path, MouseEvent event) {
2690         /* Adjust from the anchor point. */
2691         if(isMultiSelectEvent(event)) {
2692             TreePath    anchor = getAnchorSelectionPath();
2693             int         anchorRow = (anchor == null) ? -1 :
2694                                     getRowForPath(tree, anchor);
2695 
2696             if(anchorRow == -1 || tree.getSelectionModel().
2697                       getSelectionMode() == TreeSelectionModel.
2698                       SINGLE_TREE_SELECTION) {
2699                 tree.setSelectionPath(path);
2700             }
2701             else {
2702                 int          row = getRowForPath(tree, path);
2703                 TreePath     lastAnchorPath = anchor;
2704 
2705                 if (isToggleSelectionEvent(event)) {
2706                     if (tree.isRowSelected(anchorRow)) {
2707                         tree.addSelectionInterval(anchorRow, row);
2708                     } else {
2709                         tree.removeSelectionInterval(anchorRow, row);
2710                         tree.addSelectionInterval(row, row);
2711                     }
2712                 } else if(row < anchorRow) {
2713                     tree.setSelectionInterval(row, anchorRow);
2714                 } else {
2715                     tree.setSelectionInterval(anchorRow, row);
2716                 }
2717                 lastSelectedRow = row;
2718                 setAnchorSelectionPath(lastAnchorPath);
2719                 setLeadSelectionPath(path);
2720             }
2721         }
2722 
2723         // Should this event toggle the selection of this row?
2724         /* Control toggles just this node. */
2725         else if(isToggleSelectionEvent(event)) {
2726             if(tree.isPathSelected(path))
2727                 tree.removeSelectionPath(path);
2728             else
2729                 tree.addSelectionPath(path);
2730             lastSelectedRow = getRowForPath(tree, path);
2731             setAnchorSelectionPath(path);
2732             setLeadSelectionPath(path);
2733         }
2734 
2735         /* Otherwise set the selection to just this interval. */
2736         else if(SwingUtilities.isLeftMouseButton(event)) {
2737             tree.setSelectionPath(path);
2738             if(isToggleEvent(event)) {
2739                 toggleExpandState(path);
2740             }
2741         }
2742     }
2743 
2744     /**
2745      * Returns {@code true} if the node at {@code row} is a leaf.
2746      *
2747      * @param row a row
2748      * @return {@code true} if the node at {@code row} is a leaf
2749      */
2750     protected boolean isLeaf(int row) {
2751         TreePath          path = getPathForRow(tree, row);
2752 
2753         if(path != null)
2754             return treeModel.isLeaf(path.getLastPathComponent());
2755         // Have to return something here...
2756         return true;
2757     }
2758 
2759     //
2760     // The following selection methods (lead/anchor) are covers for the
2761     // methods in JTree.
2762     //
2763     private void setAnchorSelectionPath(TreePath newPath) {
2764         ignoreLAChange = true;
2765         try {
2766             tree.setAnchorSelectionPath(newPath);
2767         } finally{
2768             ignoreLAChange = false;
2769         }
2770     }
2771 
2772     private TreePath getAnchorSelectionPath() {
2773         return tree.getAnchorSelectionPath();
2774     }
2775 
2776     private void setLeadSelectionPath(TreePath newPath) {
2777         setLeadSelectionPath(newPath, false);
2778     }
2779 
2780     private void setLeadSelectionPath(TreePath newPath, boolean repaint) {
2781         Rectangle       bounds = repaint ?
2782                             getPathBounds(tree, getLeadSelectionPath()) : null;
2783 
2784         ignoreLAChange = true;
2785         try {
2786             tree.setLeadSelectionPath(newPath);
2787         } finally {
2788             ignoreLAChange = false;
2789         }
2790         leadRow = getRowForPath(tree, newPath);
2791 
2792         if (repaint) {
2793             if (bounds != null) {
2794                 tree.repaint(getRepaintPathBounds(bounds));
2795             }
2796             bounds = getPathBounds(tree, newPath);
2797             if (bounds != null) {
2798                 tree.repaint(getRepaintPathBounds(bounds));
2799             }
2800         }
2801     }
2802 
2803     private Rectangle getRepaintPathBounds(Rectangle bounds) {
2804         if (UIManager.getBoolean("Tree.repaintWholeRow")) {
2805            bounds.x = 0;
2806            bounds.width = tree.getWidth();
2807         }
2808         return bounds;
2809     }
2810 
2811     private TreePath getLeadSelectionPath() {
2812         return tree.getLeadSelectionPath();
2813     }
2814 
2815     /**
2816      * Updates the lead row of the selection.
2817      * @since 1.7
2818      */
2819     protected void updateLeadSelectionRow() {
2820         leadRow = getRowForPath(tree, getLeadSelectionPath());
2821     }
2822 
2823     /**
2824      * Returns the lead row of the selection.
2825      *
2826      * @return selection lead row
2827      * @since 1.7
2828      */
2829     protected int getLeadSelectionRow() {
2830         return leadRow;
2831     }
2832 
2833     /**
2834      * Extends the selection from the anchor to make <code>newLead</code>
2835      * the lead of the selection. This does not scroll.
2836      */
2837     private void extendSelection(TreePath newLead) {
2838         TreePath           aPath = getAnchorSelectionPath();
2839         int                aRow = (aPath == null) ? -1 :
2840                                   getRowForPath(tree, aPath);
2841         int                newIndex = getRowForPath(tree, newLead);
2842 
2843         if(aRow == -1) {
2844             tree.setSelectionRow(newIndex);
2845         }
2846         else {
2847             if(aRow < newIndex) {
2848                 tree.setSelectionInterval(aRow, newIndex);
2849             }
2850             else {
2851                 tree.setSelectionInterval(newIndex, aRow);
2852             }
2853             setAnchorSelectionPath(aPath);
2854             setLeadSelectionPath(newLead);
2855         }
2856     }
2857 
2858     /**
2859      * Invokes <code>repaint</code> on the JTree for the passed in TreePath,
2860      * <code>path</code>.
2861      */
2862     private void repaintPath(TreePath path) {
2863         if (path != null) {
2864             Rectangle bounds = getPathBounds(tree, path);
2865             if (bounds != null) {
2866                 tree.repaint(bounds.x, bounds.y, bounds.width, bounds.height);
2867             }
2868         }
2869     }
2870 
2871     /**
2872      * Updates the TreeState in response to nodes expanding/collapsing.
2873      */
2874     public class TreeExpansionHandler implements TreeExpansionListener {
2875         // NOTE: This class exists only for backward compatibility. All
2876         // its functionality has been moved into Handler. If you need to add
2877         // new functionality add it to the Handler, but make sure this
2878         // class calls into the Handler.
2879 
2880         /**
2881          * Called whenever an item in the tree has been expanded.
2882          */
2883         public void treeExpanded(TreeExpansionEvent event) {
2884             getHandler().treeExpanded(event);
2885         }
2886 
2887         /**
2888          * Called whenever an item in the tree has been collapsed.
2889          */
2890         public void treeCollapsed(TreeExpansionEvent event) {
2891             getHandler().treeCollapsed(event);
2892         }
2893     } // BasicTreeUI.TreeExpansionHandler
2894 
2895 
2896     /**
2897      * Updates the preferred size when scrolling (if necessary).
2898      */
2899     public class ComponentHandler extends ComponentAdapter implements
2900                  ActionListener {
2901         /** Timer used when inside a scrollpane and the scrollbar is
2902          * adjusting. */
2903         protected Timer                timer;
2904         /** ScrollBar that is being adjusted. */
2905         protected JScrollBar           scrollBar;
2906 
2907         public void componentMoved(ComponentEvent e) {
2908             if(timer == null) {
2909                 JScrollPane   scrollPane = getScrollPane();
2910 
2911                 if(scrollPane == null)
2912                     updateSize();
2913                 else {
2914                     scrollBar = scrollPane.getVerticalScrollBar();
2915                     if(scrollBar == null ||
2916                         !scrollBar.getValueIsAdjusting()) {
2917                         // Try the horizontal scrollbar.
2918                         if((scrollBar = scrollPane.getHorizontalScrollBar())
2919                             != null && scrollBar.getValueIsAdjusting())
2920                             startTimer();
2921                         else
2922                             updateSize();
2923                     }
2924                     else
2925                         startTimer();
2926                 }
2927             }
2928         }
2929 
2930         /**
2931          * Creates, if necessary, and starts a Timer to check if need to
2932          * resize the bounds.
2933          */
2934         protected void startTimer() {
2935             if(timer == null) {
2936                 timer = new Timer(200, this);
2937                 timer.setRepeats(true);
2938             }
2939             timer.start();
2940         }
2941 
2942         /**
2943          * Returns the {@code JScrollPane} housing the {@code JTree},
2944          * or null if one isn't found.
2945          *
2946          * @return the {@code JScrollPane} housing the {@code JTree}
2947          */
2948         protected JScrollPane getScrollPane() {
2949             Component       c = tree.getParent();
2950 
2951             while(c != null && !(c instanceof JScrollPane))
2952                 c = c.getParent();
2953             if(c instanceof JScrollPane)
2954                 return (JScrollPane)c;
2955             return null;
2956         }
2957 
2958         /**
2959          * Public as a result of Timer. If the scrollBar is null, or
2960          * not adjusting, this stops the timer and updates the sizing.
2961          */
2962         public void actionPerformed(ActionEvent ae) {
2963             if(scrollBar == null || !scrollBar.getValueIsAdjusting()) {
2964                 if(timer != null)
2965                     timer.stop();
2966                 updateSize();
2967                 timer = null;
2968                 scrollBar = null;
2969             }
2970         }
2971     } // End of BasicTreeUI.ComponentHandler
2972 
2973 
2974     /**
2975      * Forwards all TreeModel events to the TreeState.
2976      */
2977     public class TreeModelHandler implements TreeModelListener {
2978 
2979         // NOTE: This class exists only for backward compatibility. All
2980         // its functionality has been moved into Handler. If you need to add
2981         // new functionality add it to the Handler, but make sure this
2982         // class calls into the Handler.
2983 
2984         public void treeNodesChanged(TreeModelEvent e) {
2985             getHandler().treeNodesChanged(e);
2986         }
2987 
2988         public void treeNodesInserted(TreeModelEvent e) {
2989             getHandler().treeNodesInserted(e);
2990         }
2991 
2992         public void treeNodesRemoved(TreeModelEvent e) {
2993             getHandler().treeNodesRemoved(e);
2994         }
2995 
2996         public void treeStructureChanged(TreeModelEvent e) {
2997             getHandler().treeStructureChanged(e);
2998         }
2999     } // End of BasicTreeUI.TreeModelHandler
3000 
3001 
3002     /**
3003      * Listens for changes in the selection model and updates the display
3004      * accordingly.
3005      */
3006     public class TreeSelectionHandler implements TreeSelectionListener {
3007 
3008         // NOTE: This class exists only for backward compatibility. All
3009         // its functionality has been moved into Handler. If you need to add
3010         // new functionality add it to the Handler, but make sure this
3011         // class calls into the Handler.
3012 
3013         /**
3014          * Messaged when the selection changes in the tree we're displaying
3015          * for.  Stops editing, messages super and displays the changed paths.
3016          */
3017         public void valueChanged(TreeSelectionEvent event) {
3018             getHandler().valueChanged(event);
3019         }
3020     }// End of BasicTreeUI.TreeSelectionHandler
3021 
3022 
3023     /**
3024      * Listener responsible for getting cell editing events and updating
3025      * the tree accordingly.
3026      */
3027     public class CellEditorHandler implements CellEditorListener {
3028 
3029         // NOTE: This class exists only for backward compatibility. All
3030         // its functionality has been moved into Handler. If you need to add
3031         // new functionality add it to the Handler, but make sure this
3032         // class calls into the Handler.
3033 
3034         /** Messaged when editing has stopped in the tree. */
3035         public void editingStopped(ChangeEvent e) {
3036             getHandler().editingStopped(e);
3037         }
3038 
3039         /** Messaged when editing has been canceled in the tree. */
3040         public void editingCanceled(ChangeEvent e) {
3041             getHandler().editingCanceled(e);
3042         }
3043     } // BasicTreeUI.CellEditorHandler
3044 
3045 
3046     /**
3047      * This is used to get multiple key down events to appropriately generate
3048      * events.
3049      */
3050     public class KeyHandler extends KeyAdapter {
3051 
3052         // NOTE: This class exists only for backward compatibility. All
3053         // its functionality has been moved into Handler. If you need to add
3054         // new functionality add it to the Handler, but make sure this
3055         // class calls into the Handler.
3056 
3057         // Also note these fields aren't use anymore, nor does Handler have
3058         // the old functionality. This behavior worked around an old bug
3059         // in JComponent that has long since been fixed.
3060 
3061         /** Key code that is being generated for. */
3062         protected Action              repeatKeyAction;
3063 
3064         /** Set to true while keyPressed is active. */
3065         protected boolean            isKeyDown;
3066 
3067         /**
3068          * Invoked when a key has been typed.
3069          *
3070          * Moves the keyboard focus to the first element
3071          * whose first letter matches the alphanumeric key
3072          * pressed by the user. Subsequent same key presses
3073          * move the keyboard focus to the next object that
3074          * starts with the same letter.
3075          */
3076         public void keyTyped(KeyEvent e) {
3077             getHandler().keyTyped(e);
3078         }
3079 
3080         public void keyPressed(KeyEvent e) {
3081             getHandler().keyPressed(e);
3082         }
3083 
3084         public void keyReleased(KeyEvent e) {
3085             getHandler().keyReleased(e);
3086         }
3087     } // End of BasicTreeUI.KeyHandler
3088 
3089 
3090     /**
3091      * Repaints the lead selection row when focus is lost/gained.
3092      */
3093     public class FocusHandler implements FocusListener {
3094         // NOTE: This class exists only for backward compatibility. All
3095         // its functionality has been moved into Handler. If you need to add
3096         // new functionality add it to the Handler, but make sure this
3097         // class calls into the Handler.
3098 
3099         /**
3100          * Invoked when focus is activated on the tree we're in, redraws the
3101          * lead row.
3102          */
3103         public void focusGained(FocusEvent e) {
3104             getHandler().focusGained(e);
3105         }
3106 
3107         /**
3108          * Invoked when focus is activated on the tree we're in, redraws the
3109          * lead row.
3110          */
3111         public void focusLost(FocusEvent e) {
3112             getHandler().focusLost(e);
3113         }
3114     } // End of class BasicTreeUI.FocusHandler
3115 
3116 
3117     /**
3118      * Class responsible for getting size of node, method is forwarded
3119      * to BasicTreeUI method. X location does not include insets, that is
3120      * handled in getPathBounds.
3121      */
3122     // This returns locations that don't include any Insets.
3123     public class NodeDimensionsHandler extends
3124                  AbstractLayoutCache.NodeDimensions {
3125         /**
3126          * Responsible for getting the size of a particular node.
3127          */
3128         public Rectangle getNodeDimensions(Object value, int row,
3129                                            int depth, boolean expanded,
3130                                            Rectangle size) {
3131             // Return size of editing component, if editing and asking
3132             // for editing row.
3133             if(editingComponent != null && editingRow == row) {
3134                 Dimension        prefSize = editingComponent.
3135                                               getPreferredSize();
3136                 int              rh = getRowHeight();
3137 
3138                 if(rh > 0 && rh != prefSize.height)
3139                     prefSize.height = rh;
3140                 if(size != null) {
3141                     size.x = getRowX(row, depth);
3142                     size.width = prefSize.width;
3143                     size.height = prefSize.height;
3144                 }
3145                 else {
3146                     size = new Rectangle(getRowX(row, depth), 0,
3147                                          prefSize.width, prefSize.height);
3148                 }
3149                 return size;
3150             }
3151             // Not editing, use renderer.
3152             if(currentCellRenderer != null) {
3153                 Component          aComponent;
3154 
3155                 aComponent = currentCellRenderer.getTreeCellRendererComponent
3156                     (tree, value, tree.isRowSelected(row),
3157                      expanded, treeModel.isLeaf(value), row,
3158                      false);
3159                 if(tree != null) {
3160                     // Only ever removed when UI changes, this is OK!
3161                     rendererPane.add(aComponent);
3162                     aComponent.validate();
3163                 }
3164                 Dimension        prefSize = aComponent.getPreferredSize();
3165 
3166                 if(size != null) {
3167                     size.x = getRowX(row, depth);
3168                     size.width = prefSize.width;
3169                     size.height = prefSize.height;
3170                 }
3171                 else {
3172                     size = new Rectangle(getRowX(row, depth), 0,
3173                                          prefSize.width, prefSize.height);
3174                 }
3175                 return size;
3176             }
3177             return null;
3178         }
3179 
3180         /**
3181          * Returns amount to indent the given row.
3182          *
3183          * @param row a row
3184          * @param depth a depth
3185          * @return amount to indent the given row
3186          */
3187         protected int getRowX(int row, int depth) {
3188             return BasicTreeUI.this.getRowX(row, depth);
3189         }
3190 
3191     } // End of class BasicTreeUI.NodeDimensionsHandler
3192 
3193 
3194     /**
3195      * TreeMouseListener is responsible for updating the selection
3196      * based on mouse events.
3197      */
3198     public class MouseHandler extends MouseAdapter implements MouseMotionListener
3199  {
3200         // NOTE: This class exists only for backward compatibility. All
3201         // its functionality has been moved into Handler. If you need to add
3202         // new functionality add it to the Handler, but make sure this
3203         // class calls into the Handler.
3204 
3205         /**
3206          * Invoked when a mouse button has been pressed on a component.
3207          */
3208         public void mousePressed(MouseEvent e) {
3209             getHandler().mousePressed(e);
3210         }
3211 
3212         public void mouseDragged(MouseEvent e) {
3213             getHandler().mouseDragged(e);
3214         }
3215 
3216         /**
3217          * Invoked when the mouse button has been moved on a component
3218          * (with no buttons no down).
3219          * @since 1.4
3220          */
3221         public void mouseMoved(MouseEvent e) {
3222             getHandler().mouseMoved(e);
3223         }
3224 
3225         public void mouseReleased(MouseEvent e) {
3226             getHandler().mouseReleased(e);
3227         }
3228     } // End of BasicTreeUI.MouseHandler
3229 
3230 
3231     /**
3232      * PropertyChangeListener for the tree. Updates the appropriate
3233      * variable, or TreeState, based on what changes.
3234      */
3235     public class PropertyChangeHandler implements
3236                        PropertyChangeListener {
3237 
3238         // NOTE: This class exists only for backward compatibility. All
3239         // its functionality has been moved into Handler. If you need to add
3240         // new functionality add it to the Handler, but make sure this
3241         // class calls into the Handler.
3242 
3243         public void propertyChange(PropertyChangeEvent event) {
3244             getHandler().propertyChange(event);
3245         }
3246     } // End of BasicTreeUI.PropertyChangeHandler
3247 
3248 
3249     /**
3250      * Listener on the TreeSelectionModel, resets the row selection if
3251      * any of the properties of the model change.
3252      */
3253     public class SelectionModelPropertyChangeHandler implements
3254                       PropertyChangeListener {
3255 
3256         // NOTE: This class exists only for backward compatibility. All
3257         // its functionality has been moved into Handler. If you need to add
3258         // new functionality add it to the Handler, but make sure this
3259         // class calls into the Handler.
3260 
3261         public void propertyChange(PropertyChangeEvent event) {
3262             getHandler().propertyChange(event);
3263         }
3264     } // End of BasicTreeUI.SelectionModelPropertyChangeHandler
3265 
3266 
3267     /**
3268      * <code>TreeTraverseAction</code> is the action used for left/right keys.
3269      * Will toggle the expandedness of a node, as well as potentially
3270      * incrementing the selection.
3271      */
3272     @SuppressWarnings("serial") // Superclass is not serializable across versions
3273     public class TreeTraverseAction extends AbstractAction {
3274         /** Determines direction to traverse, 1 means expand, -1 means
3275           * collapse. */
3276         protected int direction;
3277         /** True if the selection is reset, false means only the lead path
3278          * changes. */
3279         private boolean changeSelection;
3280 
3281         /**
3282          * Constructs a new instance of {@code TreeTraverseAction}.
3283          *
3284          * @param direction the direction
3285          * @param name the name of action
3286          */
3287         public TreeTraverseAction(int direction, String name) {
3288             this(direction, name, true);
3289         }
3290 
3291         private TreeTraverseAction(int direction, String name,
3292                                    boolean changeSelection) {
3293             this.direction = direction;
3294             this.changeSelection = changeSelection;
3295         }
3296 
3297         public void actionPerformed(ActionEvent e) {
3298             if (tree != null) {
3299                 SHARED_ACTION.traverse(tree, BasicTreeUI.this, direction,
3300                                        changeSelection);
3301             }
3302         }
3303 
3304         public boolean isEnabled() { return (tree != null &&
3305                                              tree.isEnabled()); }
3306     } // BasicTreeUI.TreeTraverseAction
3307 
3308 
3309     /** TreePageAction handles page up and page down events.
3310       */
3311     @SuppressWarnings("serial") // Superclass is not serializable across versions
3312     public class TreePageAction extends AbstractAction {
3313         /** Specifies the direction to adjust the selection by. */
3314         protected int         direction;
3315         /** True indicates should set selection from anchor path. */
3316         private boolean       addToSelection;
3317         private boolean       changeSelection;
3318 
3319         /**
3320          * Constructs a new instance of {@code TreePageAction}.
3321          *
3322          * @param direction the direction
3323          * @param name the name of action
3324          */
3325         public TreePageAction(int direction, String name) {
3326             this(direction, name, false, true);
3327         }
3328 
3329         private TreePageAction(int direction, String name,
3330                                boolean addToSelection,
3331                                boolean changeSelection) {
3332             this.direction = direction;
3333             this.addToSelection = addToSelection;
3334             this.changeSelection = changeSelection;
3335         }
3336 
3337         public void actionPerformed(ActionEvent e) {
3338             if (tree != null) {
3339                 SHARED_ACTION.page(tree, BasicTreeUI.this, direction,
3340                                    addToSelection, changeSelection);
3341             }
3342         }
3343 
3344         public boolean isEnabled() { return (tree != null &&
3345                                              tree.isEnabled()); }
3346 
3347     } // BasicTreeUI.TreePageAction
3348 
3349 
3350     /** TreeIncrementAction is used to handle up/down actions.  Selection
3351       * is moved up or down based on direction.
3352       */
3353     @SuppressWarnings("serial") // Superclass is not serializable across versions
3354     public class TreeIncrementAction extends AbstractAction  {
3355         /** Specifies the direction to adjust the selection by. */
3356         protected int         direction;
3357         /** If true the new item is added to the selection, if false the
3358          * selection is reset. */
3359         private boolean       addToSelection;
3360         private boolean       changeSelection;
3361 
3362         /**
3363          * Constructs a new instance of {@code TreeIncrementAction}.
3364          *
3365          * @param direction the direction
3366          * @param name the name of action
3367          */
3368         public TreeIncrementAction(int direction, String name) {
3369             this(direction, name, false, true);
3370         }
3371 
3372         private TreeIncrementAction(int direction, String name,
3373                                    boolean addToSelection,
3374                                     boolean changeSelection) {
3375             this.direction = direction;
3376             this.addToSelection = addToSelection;
3377             this.changeSelection = changeSelection;
3378         }
3379 
3380         public void actionPerformed(ActionEvent e) {
3381             if (tree != null) {
3382                 SHARED_ACTION.increment(tree, BasicTreeUI.this, direction,
3383                                         addToSelection, changeSelection);
3384             }
3385         }
3386 
3387         public boolean isEnabled() { return (tree != null &&
3388                                              tree.isEnabled()); }
3389 
3390     } // End of class BasicTreeUI.TreeIncrementAction
3391 
3392     /**
3393       * TreeHomeAction is used to handle end/home actions.
3394       * Scrolls either the first or last cell to be visible based on
3395       * direction.
3396       */
3397     @SuppressWarnings("serial") // Superclass is not serializable across versions
3398     public class TreeHomeAction extends AbstractAction {
3399         /**
3400          * The direction.
3401          */
3402         protected int            direction;
3403         /** Set to true if append to selection. */
3404         private boolean          addToSelection;
3405         private boolean          changeSelection;
3406 
3407         /**
3408          * Constructs a new instance of {@code TreeHomeAction}.
3409          *
3410          * @param direction the direction
3411          * @param name the name of action
3412          */
3413         public TreeHomeAction(int direction, String name) {
3414             this(direction, name, false, true);
3415         }
3416 
3417         private TreeHomeAction(int direction, String name,
3418                                boolean addToSelection,
3419                                boolean changeSelection) {
3420             this.direction = direction;
3421             this.changeSelection = changeSelection;
3422             this.addToSelection = addToSelection;
3423         }
3424 
3425         public void actionPerformed(ActionEvent e) {
3426             if (tree != null) {
3427                 SHARED_ACTION.home(tree, BasicTreeUI.this, direction,
3428                                    addToSelection, changeSelection);
3429             }
3430         }
3431 
3432         public boolean isEnabled() { return (tree != null &&
3433                                              tree.isEnabled()); }
3434 
3435     } // End of class BasicTreeUI.TreeHomeAction
3436 
3437 
3438     /**
3439       * For the first selected row expandedness will be toggled.
3440       */
3441     @SuppressWarnings("serial") // Superclass is not serializable across versions
3442     public class TreeToggleAction extends AbstractAction {
3443         /**
3444          * Constructs a new instance of {@code TreeToggleAction}.
3445          *
3446          * @param name the name of action
3447          */
3448         public TreeToggleAction(String name) {
3449         }
3450 
3451         public void actionPerformed(ActionEvent e) {
3452             if(tree != null) {
3453                 SHARED_ACTION.toggle(tree, BasicTreeUI.this);
3454             }
3455         }
3456 
3457         public boolean isEnabled() { return (tree != null &&
3458                                              tree.isEnabled()); }
3459 
3460     } // End of class BasicTreeUI.TreeToggleAction
3461 
3462 
3463     /**
3464      * ActionListener that invokes cancelEditing when action performed.
3465      */
3466     @SuppressWarnings("serial") // Superclass is not serializable across versions
3467     public class TreeCancelEditingAction extends AbstractAction {
3468         /**
3469          * Constructs a new instance of {@code TreeCancelEditingAction}.
3470          *
3471          * @param name the name of action
3472          */
3473         public TreeCancelEditingAction(String name) {
3474         }
3475 
3476         public void actionPerformed(ActionEvent e) {
3477             if(tree != null) {
3478                 SHARED_ACTION.cancelEditing(tree, BasicTreeUI.this);
3479             }
3480         }
3481 
3482         public boolean isEnabled() { return (tree != null &&
3483                                              tree.isEnabled() &&
3484                                              isEditing(tree)); }
3485     } // End of class BasicTreeUI.TreeCancelEditingAction
3486 
3487 
3488     /**
3489       * MouseInputHandler handles passing all mouse events,
3490       * including mouse motion events, until the mouse is released to
3491       * the destination it is constructed with. It is assumed all the
3492       * events are currently target at source.
3493       */
3494     public class MouseInputHandler extends Object implements
3495                      MouseInputListener
3496     {
3497         /** Source that events are coming from. */
3498         protected Component        source;
3499         /** Destination that receives all events. */
3500         protected Component        destination;
3501         private Component          focusComponent;
3502         private boolean            dispatchedEvent;
3503 
3504         /**
3505          * Constructs a new instance of {@code MouseInputHandler}.
3506          *
3507          * @param source a source component
3508          * @param destination a destination component
3509          * @param event a mouse event
3510          */
3511         public MouseInputHandler(Component source, Component destination,
3512                                       MouseEvent event){
3513             this(source, destination, event, null);
3514         }
3515 
3516         MouseInputHandler(Component source, Component destination,
3517                           MouseEvent event, Component focusComponent) {
3518             this.source = source;
3519             this.destination = destination;
3520             this.source.addMouseListener(this);
3521             this.source.addMouseMotionListener(this);
3522 
3523             SwingUtilities2.setSkipClickCount(destination,
3524                                               event.getClickCount() - 1);
3525 
3526             /* Dispatch the editing event! */
3527             destination.dispatchEvent(SwingUtilities.convertMouseEvent
3528                                           (source, event, destination));
3529             this.focusComponent = focusComponent;
3530         }
3531 
3532         public void mouseClicked(MouseEvent e) {
3533             if(destination != null) {
3534                 dispatchedEvent = true;
3535                 destination.dispatchEvent(SwingUtilities.convertMouseEvent
3536                                           (source, e, destination));
3537             }
3538         }
3539 
3540         public void mousePressed(MouseEvent e) {
3541         }
3542 
3543         public void mouseReleased(MouseEvent e) {
3544             if(destination != null)
3545                 destination.dispatchEvent(SwingUtilities.convertMouseEvent
3546                                           (source, e, destination));
3547             removeFromSource();
3548         }
3549 
3550         public void mouseEntered(MouseEvent e) {
3551             if (!SwingUtilities.isLeftMouseButton(e)) {
3552                 removeFromSource();
3553             }
3554         }
3555 
3556         public void mouseExited(MouseEvent e) {
3557             if (!SwingUtilities.isLeftMouseButton(e)) {
3558                 removeFromSource();
3559             }
3560         }
3561 
3562         public void mouseDragged(MouseEvent e) {
3563             if(destination != null) {
3564                 dispatchedEvent = true;
3565                 destination.dispatchEvent(SwingUtilities.convertMouseEvent
3566                                           (source, e, destination));
3567             }
3568         }
3569 
3570         public void mouseMoved(MouseEvent e) {
3571             removeFromSource();
3572         }
3573 
3574         /**
3575          * Removes an event from the source.
3576          */
3577         protected void removeFromSource() {
3578             if(source != null) {
3579                 source.removeMouseListener(this);
3580                 source.removeMouseMotionListener(this);
3581                 if (focusComponent != null &&
3582                       focusComponent == destination && !dispatchedEvent &&
3583                       (focusComponent instanceof JTextField)) {
3584                     ((JTextField)focusComponent).selectAll();
3585                 }
3586             }
3587             source = destination = null;
3588         }
3589 
3590     } // End of class BasicTreeUI.MouseInputHandler
3591 
3592     private static final TransferHandler defaultTransferHandler = new TreeTransferHandler();
3593 
3594     @SuppressWarnings("serial") // JDK-implementation class
3595     static class TreeTransferHandler extends TransferHandler implements UIResource, Comparator<TreePath> {
3596 
3597         private JTree tree;
3598 
3599         /**
3600          * Create a Transferable to use as the source for a data transfer.
3601          *
3602          * @param c  The component holding the data to be transfered.  This
3603          *  argument is provided to enable sharing of TransferHandlers by
3604          *  multiple components.
3605          * @return  The representation of the data to be transfered.
3606          *
3607          */
3608         protected Transferable createTransferable(JComponent c) {
3609             if (c instanceof JTree) {
3610                 tree = (JTree) c;
3611                 TreePath[] paths = tree.getSelectionPaths();
3612 
3613                 if (paths == null || paths.length == 0) {
3614                     return null;
3615                 }
3616 
3617                 StringBuilder plainStr = new StringBuilder();
3618                 StringBuilder htmlStr = new StringBuilder();
3619 
3620                 htmlStr.append("<html>\n<body>\n<ul>\n");
3621 
3622                 TreeModel model = tree.getModel();
3623                 TreePath lastPath = null;
3624                 TreePath[] displayPaths = getDisplayOrderPaths(paths);
3625 
3626                 for (TreePath path : displayPaths) {
3627                     Object node = path.getLastPathComponent();
3628                     boolean leaf = model.isLeaf(node);
3629                     String label = getDisplayString(path, true, leaf);
3630 
3631                     plainStr.append(label).append('\n');
3632                     htmlStr.append("  <li>").append(label).append('\n');
3633                 }
3634 
3635                 // remove the last newline
3636                 plainStr.deleteCharAt(plainStr.length() - 1);
3637                 htmlStr.append("</ul>\n</body>\n</html>");
3638 
3639                 tree = null;
3640 
3641                 return new BasicTransferable(plainStr.toString(), htmlStr.toString());
3642             }
3643 
3644             return null;
3645         }
3646 
3647         public int compare(TreePath o1, TreePath o2) {
3648             int row1 = tree.getRowForPath(o1);
3649             int row2 = tree.getRowForPath(o2);
3650             return row1 - row2;
3651         }
3652 
3653         String getDisplayString(TreePath path, boolean selected, boolean leaf) {
3654             int row = tree.getRowForPath(path);
3655             boolean hasFocus = tree.getLeadSelectionRow() == row;
3656             Object node = path.getLastPathComponent();
3657             return tree.convertValueToText(node, selected, tree.isExpanded(row),
3658                                            leaf, row, hasFocus);
3659         }
3660 
3661         /**
3662          * Selection paths are in selection order.  The conversion to
3663          * HTML requires display order.  This method resorts the paths
3664          * to be in the display order.
3665          */
3666         TreePath[] getDisplayOrderPaths(TreePath[] paths) {
3667             // sort the paths to display order rather than selection order
3668             ArrayList<TreePath> selOrder = new ArrayList<TreePath>();
3669             for (TreePath path : paths) {
3670                 selOrder.add(path);
3671             }
3672             Collections.sort(selOrder, this);
3673             int n = selOrder.size();
3674             TreePath[] displayPaths = new TreePath[n];
3675             for (int i = 0; i < n; i++) {
3676                 displayPaths[i] = selOrder.get(i);
3677             }
3678             return displayPaths;
3679         }
3680 
3681         public int getSourceActions(JComponent c) {
3682             return COPY;
3683         }
3684 
3685     }
3686 
3687 
3688     private class Handler implements CellEditorListener, FocusListener,
3689                   KeyListener, MouseListener, MouseMotionListener,
3690                   PropertyChangeListener, TreeExpansionListener,
3691                   TreeModelListener, TreeSelectionListener,
3692                   BeforeDrag {
3693         //
3694         // KeyListener
3695         //
3696         private String prefix = "";
3697         private String typedString = "";
3698         private long lastTime = 0L;
3699 
3700         /**
3701          * Invoked when a key has been typed.
3702          *
3703          * Moves the keyboard focus to the first element whose prefix matches the
3704          * sequence of alphanumeric keys pressed by the user with delay less
3705          * than value of <code>timeFactor</code> property (or 1000 milliseconds
3706          * if it is not defined). Subsequent same key presses move the keyboard
3707          * focus to the next object that starts with the same letter until another
3708          * key is pressed, then it is treated as the prefix with appropriate number
3709          * of the same letters followed by first typed another letter.
3710          */
3711         public void keyTyped(KeyEvent e) {
3712             // handle first letter navigation
3713             if(tree != null && tree.getRowCount()>0 && tree.hasFocus() &&
3714                tree.isEnabled()) {
3715                 if (e.isAltDown() || BasicGraphicsUtils.isMenuShortcutKeyDown(e) ||
3716                     isNavigationKey(e)) {
3717                     return;
3718                 }
3719                 boolean startingFromSelection = true;
3720 
3721                 char c = e.getKeyChar();
3722 
3723                 long time = e.getWhen();
3724                 int startingRow = tree.getLeadSelectionRow();
3725                 if (time - lastTime < timeFactor) {
3726                     typedString += c;
3727                     if((prefix.length() == 1) && (c == prefix.charAt(0))) {
3728                         // Subsequent same key presses move the keyboard focus to the next
3729                         // object that starts with the same letter.
3730                         startingRow++;
3731                     } else {
3732                         prefix = typedString;
3733                     }
3734                 } else {
3735                     startingRow++;
3736                     typedString = "" + c;
3737                     prefix = typedString;
3738                 }
3739                 lastTime = time;
3740 
3741                 if (startingRow < 0 || startingRow >= tree.getRowCount()) {
3742                     startingFromSelection = false;
3743                     startingRow = 0;
3744                 }
3745                 TreePath path = tree.getNextMatch(prefix, startingRow,
3746                                                   Position.Bias.Forward);
3747                 if (path != null) {
3748                     tree.setSelectionPath(path);
3749                     int row = getRowForPath(tree, path);
3750                     ensureRowsAreVisible(row, row);
3751                 } else if (startingFromSelection) {
3752                     path = tree.getNextMatch(prefix, 0,
3753                                              Position.Bias.Forward);
3754                     if (path != null) {
3755                         tree.setSelectionPath(path);
3756                         int row = getRowForPath(tree, path);
3757                         ensureRowsAreVisible(row, row);
3758                     }
3759                 }
3760             }
3761         }
3762 
3763         /**
3764          * Invoked when a key has been pressed.
3765          *
3766          * Checks to see if the key event is a navigation key to prevent
3767          * dispatching these keys for the first letter navigation.
3768          */
3769         public void keyPressed(KeyEvent e) {
3770             if (tree != null && isNavigationKey(e)) {
3771                 prefix = "";
3772                 typedString = "";
3773                 lastTime = 0L;
3774             }
3775         }
3776 
3777         public void keyReleased(KeyEvent e) {
3778         }
3779 
3780         /**
3781          * Returns whether or not the supplied key event maps to a key that is used for
3782          * navigation.  This is used for optimizing key input by only passing non-
3783          * navigation keys to the first letter navigation mechanism.
3784          */
3785         private boolean isNavigationKey(KeyEvent event) {
3786             InputMap inputMap = tree.getInputMap(JComponent.WHEN_ANCESTOR_OF_FOCUSED_COMPONENT);
3787             KeyStroke key = KeyStroke.getKeyStrokeForEvent(event);
3788 
3789             return inputMap != null && inputMap.get(key) != null;
3790         }
3791 
3792 
3793         //
3794         // PropertyChangeListener
3795         //
3796         public void propertyChange(PropertyChangeEvent event) {
3797             if (event.getSource() == treeSelectionModel) {
3798                 treeSelectionModel.resetRowSelection();
3799             }
3800             else if(event.getSource() == tree) {
3801                 String              changeName = event.getPropertyName();
3802 
3803                 if (changeName == JTree.LEAD_SELECTION_PATH_PROPERTY) {
3804                     if (!ignoreLAChange) {
3805                         updateLeadSelectionRow();
3806                         repaintPath((TreePath)event.getOldValue());
3807                         repaintPath((TreePath)event.getNewValue());
3808                     }
3809                 }
3810                 else if (changeName == JTree.ANCHOR_SELECTION_PATH_PROPERTY) {
3811                     if (!ignoreLAChange) {
3812                         repaintPath((TreePath)event.getOldValue());
3813                         repaintPath((TreePath)event.getNewValue());
3814                     }
3815                 }
3816                 if(changeName == JTree.CELL_RENDERER_PROPERTY) {
3817                     setCellRenderer((TreeCellRenderer)event.getNewValue());
3818                     redoTheLayout();
3819                 }
3820                 else if(changeName == JTree.TREE_MODEL_PROPERTY) {
3821                     setModel((TreeModel)event.getNewValue());
3822                 }
3823                 else if(changeName == JTree.ROOT_VISIBLE_PROPERTY) {
3824                     setRootVisible(((Boolean)event.getNewValue()).
3825                                    booleanValue());
3826                 }
3827                 else if(changeName == JTree.SHOWS_ROOT_HANDLES_PROPERTY) {
3828                     setShowsRootHandles(((Boolean)event.getNewValue()).
3829                                         booleanValue());
3830                 }
3831                 else if(changeName == JTree.ROW_HEIGHT_PROPERTY) {
3832                     setRowHeight(((Integer)event.getNewValue()).
3833                                  intValue());
3834                 }
3835                 else if(changeName == JTree.CELL_EDITOR_PROPERTY) {
3836                     setCellEditor((TreeCellEditor)event.getNewValue());
3837                 }
3838                 else if(changeName == JTree.EDITABLE_PROPERTY) {
3839                     setEditable(((Boolean)event.getNewValue()).booleanValue());
3840                 }
3841                 else if(changeName == JTree.LARGE_MODEL_PROPERTY) {
3842                     setLargeModel(tree.isLargeModel());
3843                 }
3844                 else if(changeName == JTree.SELECTION_MODEL_PROPERTY) {
3845                     setSelectionModel(tree.getSelectionModel());
3846                 }
3847                 else if(changeName == "font") {
3848                     completeEditing();
3849                     if(treeState != null)
3850                         treeState.invalidateSizes();
3851                     updateSize();
3852                 }
3853                 else if (changeName == "componentOrientation") {
3854                     if (tree != null) {
3855                         leftToRight = BasicGraphicsUtils.isLeftToRight(tree);
3856                         redoTheLayout();
3857                         tree.treeDidChange();
3858 
3859                         InputMap km = getInputMap(JComponent.WHEN_FOCUSED);
3860                         SwingUtilities.replaceUIInputMap(tree,
3861                                                 JComponent.WHEN_FOCUSED, km);
3862                     }
3863                 } else if ("dropLocation" == changeName) {
3864                     JTree.DropLocation oldValue = (JTree.DropLocation)event.getOldValue();
3865                     repaintDropLocation(oldValue);
3866                     repaintDropLocation(tree.getDropLocation());
3867                 }
3868             }
3869         }
3870 
3871         private void repaintDropLocation(JTree.DropLocation loc) {
3872             if (loc == null) {
3873                 return;
3874             }
3875 
3876             Rectangle r;
3877 
3878             if (isDropLine(loc)) {
3879                 r = getDropLineRect(loc);
3880             } else {
3881                 r = tree.getPathBounds(loc.getPath());
3882             }
3883 
3884             if (r != null) {
3885                 tree.repaint(r);
3886             }
3887         }
3888 
3889         //
3890         // MouseListener
3891         //
3892 
3893         // Whether or not the mouse press (which is being considered as part
3894         // of a drag sequence) also caused the selection change to be fully
3895         // processed.
3896         private boolean dragPressDidSelection;
3897 
3898         // Set to true when a drag gesture has been fully recognized and DnD
3899         // begins. Use this to ignore further mouse events which could be
3900         // delivered if DnD is cancelled (via ESCAPE for example)
3901         private boolean dragStarted;
3902 
3903         // The path over which the press occurred and the press event itself
3904         private TreePath pressedPath;
3905         private MouseEvent pressedEvent;
3906 
3907         // Used to detect whether the press event causes a selection change.
3908         // If it does, we won't try to start editing on the release.
3909         private boolean valueChangedOnPress;
3910 
3911         private boolean isActualPath(TreePath path, int x, int y) {
3912             if (path == null) {
3913                 return false;
3914             }
3915 
3916             Rectangle bounds = getPathBounds(tree, path);
3917             if (bounds == null || y > (bounds.y + bounds.height)) {
3918                 return false;
3919             }
3920 
3921             return (x >= bounds.x) && (x <= (bounds.x + bounds.width));
3922         }
3923 
3924         public void mouseClicked(MouseEvent e) {
3925         }
3926 
3927         public void mouseEntered(MouseEvent e) {
3928         }
3929 
3930         public void mouseExited(MouseEvent e) {
3931         }
3932 
3933         /**
3934          * Invoked when a mouse button has been pressed on a component.
3935          */
3936         public void mousePressed(MouseEvent e) {
3937             if (SwingUtilities2.shouldIgnore(e, tree)) {
3938                 return;
3939             }
3940 
3941             // if we can't stop any ongoing editing, do nothing
3942             if (isEditing(tree) && tree.getInvokesStopCellEditing()
3943                                 && !stopEditing(tree)) {
3944                 return;
3945             }
3946 
3947             completeEditing();
3948 
3949             pressedPath = getClosestPathForLocation(tree, e.getX(), e.getY());
3950 
3951             if (tree.getDragEnabled()) {
3952                 mousePressedDND(e);
3953             } else {
3954                 SwingUtilities2.adjustFocus(tree);
3955                 handleSelection(e);
3956             }
3957         }
3958 
3959         private void mousePressedDND(MouseEvent e) {
3960             pressedEvent = e;
3961             boolean grabFocus = true;
3962             dragStarted = false;
3963             valueChangedOnPress = false;
3964 
3965             // if we have a valid path and this is a drag initiating event
3966             if (isActualPath(pressedPath, e.getX(), e.getY()) &&
3967                     DragRecognitionSupport.mousePressed(e)) {
3968 
3969                 dragPressDidSelection = false;
3970 
3971                 if (BasicGraphicsUtils.isMenuShortcutKeyDown(e)) {
3972                     // do nothing for control - will be handled on release
3973                     // or when drag starts
3974                     return;
3975                 } else if (!e.isShiftDown() && tree.isPathSelected(pressedPath)) {
3976                     // clicking on something that's already selected
3977                     // and need to make it the lead now
3978                     setAnchorSelectionPath(pressedPath);
3979                     setLeadSelectionPath(pressedPath, true);
3980                     return;
3981                 }
3982 
3983                 dragPressDidSelection = true;
3984 
3985                 // could be a drag initiating event - don't grab focus
3986                 grabFocus = false;
3987             }
3988 
3989             if (grabFocus) {
3990                 SwingUtilities2.adjustFocus(tree);
3991             }
3992 
3993             handleSelection(e);
3994         }
3995 
3996         void handleSelection(MouseEvent e) {
3997             if(pressedPath != null) {
3998                 Rectangle bounds = getPathBounds(tree, pressedPath);
3999 
4000                 if (bounds == null || e.getY() >= (bounds.y + bounds.height)) {
4001                     return;
4002                 }
4003 
4004                 // Preferably checkForClickInExpandControl could take
4005                 // the Event to do this it self!
4006                 if(SwingUtilities.isLeftMouseButton(e)) {
4007                     checkForClickInExpandControl(pressedPath, e.getX(), e.getY());
4008                     
4009                     if(tree.getClientProperty("Tree.enableDoubleClickOnExpandControl") == TRUE)
4010                         // without this return statement, when double click on 
4011                         // the expand control, only the first click is processed. 
4012                         // used by WindowsNavigationTree
4013                         if (isLocationInExpandControl(pressedPath, e.getX(), e.getY())) 
4014                             return;
4015                 }
4016 
4017                 int x = e.getX();
4018 
4019                 // Perhaps they clicked the cell itself. If so,
4020                 // select it.
4021                 if (x >= bounds.x && x < (bounds.x + bounds.width)) {
4022                     if (tree.getDragEnabled() || !startEditing(pressedPath, e)) {
4023                         selectPathForEvent(pressedPath, e);
4024                     }
4025                 }
4026             }
4027         }
4028 
4029         public void dragStarting(MouseEvent me) {
4030             dragStarted = true;
4031 
4032             if (BasicGraphicsUtils.isMenuShortcutKeyDown(me)) {
4033                 tree.addSelectionPath(pressedPath);
4034                 setAnchorSelectionPath(pressedPath);
4035                 setLeadSelectionPath(pressedPath, true);
4036             }
4037 
4038             pressedEvent = null;
4039             pressedPath = null;
4040         }
4041 
4042         public void mouseDragged(MouseEvent e) {
4043             if (SwingUtilities2.shouldIgnore(e, tree)) {
4044                 return;
4045             }
4046 
4047             if (tree.getDragEnabled()) {
4048                 DragRecognitionSupport.mouseDragged(e, this);
4049             }
4050         }
4051 
4052         /**
4053          * Invoked when the mouse button has been moved on a component
4054          * (with no buttons no down).
4055          */
4056         public void mouseMoved(MouseEvent e) {
4057         }
4058 
4059         public void mouseReleased(MouseEvent e) {
4060             if (SwingUtilities2.shouldIgnore(e, tree)) {
4061                 return;
4062             }
4063 
4064             if (tree.getDragEnabled()) {
4065                 mouseReleasedDND(e);
4066             }
4067 
4068             pressedEvent = null;
4069             pressedPath = null;
4070         }
4071 
4072         private void mouseReleasedDND(MouseEvent e) {
4073             MouseEvent me = DragRecognitionSupport.mouseReleased(e);
4074             if (me != null) {
4075                 SwingUtilities2.adjustFocus(tree);
4076                 if (!dragPressDidSelection) {
4077                     handleSelection(me);
4078                 }
4079             }
4080 
4081             if (!dragStarted) {
4082 
4083                 // Note: We don't give the tree a chance to start editing if the
4084                 // mouse press caused a selection change. Otherwise the default
4085                 // tree cell editor will start editing on EVERY press and
4086                 // release. If it turns out that this affects some editors, we
4087                 // can always parameterize this with a client property. ex:
4088                 //
4089                 // if (pressedPath != null &&
4090                 //         (Boolean.TRUE == tree.getClientProperty("Tree.DnD.canEditOnValueChange") ||
4091                 //          !valueChangedOnPress) && ...
4092                 if (pressedPath != null && !valueChangedOnPress &&
4093                         isActualPath(pressedPath, pressedEvent.getX(), pressedEvent.getY())) {
4094 
4095                     startEditingOnRelease(pressedPath, pressedEvent, e);
4096                 }
4097             }
4098         }
4099 
4100         //
4101         // FocusListener
4102         //
4103         public void focusGained(FocusEvent e) {
4104             if(tree != null) {
4105                 Rectangle                 pBounds;
4106 
4107                 pBounds = getPathBounds(tree, tree.getLeadSelectionPath());
4108                 if(pBounds != null)
4109                     tree.repaint(getRepaintPathBounds(pBounds));
4110                 pBounds = getPathBounds(tree, getLeadSelectionPath());
4111                 if(pBounds != null)
4112                     tree.repaint(getRepaintPathBounds(pBounds));
4113             }
4114         }
4115 
4116         public void focusLost(FocusEvent e) {
4117             focusGained(e);
4118         }
4119 
4120         //
4121         // CellEditorListener
4122         //
4123         public void editingStopped(ChangeEvent e) {
4124             completeEditing(false, false, true);
4125         }
4126 
4127         /** Messaged when editing has been canceled in the tree. */
4128         public void editingCanceled(ChangeEvent e) {
4129             completeEditing(false, false, false);
4130         }
4131 
4132 
4133         //
4134         // TreeSelectionListener
4135         //
4136         public void valueChanged(TreeSelectionEvent event) {
4137             valueChangedOnPress = true;
4138 
4139             // Stop editing
4140             completeEditing();
4141             // Make sure all the paths are visible, if necessary.
4142             // PENDING: This should be tweaked when isAdjusting is added
4143             if(tree.getExpandsSelectedPaths() && treeSelectionModel != null) {
4144                 TreePath[]           paths = treeSelectionModel
4145                                          .getSelectionPaths();
4146 
4147                 if(paths != null) {
4148                     for(int counter = paths.length - 1; counter >= 0;
4149                         counter--) {
4150                         TreePath path = paths[counter].getParentPath();
4151                         boolean expand = true;
4152 
4153                         while (path != null) {
4154                             // Indicates this path isn't valid anymore,
4155                             // we shouldn't attempt to expand it then.
4156                             if (treeModel.isLeaf(path.getLastPathComponent())){
4157                                 expand = false;
4158                                 path = null;
4159                             }
4160                             else {
4161                                 path = path.getParentPath();
4162                             }
4163                         }
4164                         if (expand) {
4165                             tree.makeVisible(paths[counter]);
4166                         }
4167                     }
4168                 }
4169             }
4170 
4171             TreePath oldLead = getLeadSelectionPath();
4172             lastSelectedRow = tree.getMinSelectionRow();
4173             TreePath lead = tree.getSelectionModel().getLeadSelectionPath();
4174             setAnchorSelectionPath(lead);
4175             setLeadSelectionPath(lead);
4176 
4177             TreePath[]       changedPaths = event.getPaths();
4178             Rectangle        nodeBounds;
4179             Rectangle        visRect = tree.getVisibleRect();
4180             boolean          paintPaths = true;
4181             int              nWidth = tree.getWidth();
4182 
4183             if(changedPaths != null) {
4184                 int              counter, maxCounter = changedPaths.length;
4185 
4186                 if(maxCounter > 4) {
4187                     tree.repaint();
4188                     paintPaths = false;
4189                 }
4190                 else {
4191                     for (counter = 0; counter < maxCounter; counter++) {
4192                         nodeBounds = getPathBounds(tree,
4193                                                    changedPaths[counter]);
4194                         if(nodeBounds != null &&
4195                            visRect.intersects(nodeBounds))
4196                             tree.repaint(0, nodeBounds.y, nWidth,
4197                                          nodeBounds.height);
4198                     }
4199                 }
4200             }
4201             if(paintPaths) {
4202                 nodeBounds = getPathBounds(tree, oldLead);
4203                 if(nodeBounds != null && visRect.intersects(nodeBounds))
4204                     tree.repaint(0, nodeBounds.y, nWidth, nodeBounds.height);
4205                 nodeBounds = getPathBounds(tree, lead);
4206                 if(nodeBounds != null && visRect.intersects(nodeBounds))
4207                     tree.repaint(0, nodeBounds.y, nWidth, nodeBounds.height);
4208             }
4209         }
4210 
4211 
4212         //
4213         // TreeExpansionListener
4214         //
4215         public void treeExpanded(TreeExpansionEvent event) {
4216             if(event != null && tree != null) {
4217                 TreePath      path = event.getPath();
4218 
4219                 updateExpandedDescendants(path);
4220             }
4221         }
4222 
4223         public void treeCollapsed(TreeExpansionEvent event) {
4224             if(event != null && tree != null) {
4225                 TreePath        path = event.getPath();
4226 
4227                 completeEditing();
4228                 if(path != null && tree.isVisible(path)) {
4229                     treeState.setExpandedState(path, false);
4230                     updateLeadSelectionRow();
4231                     updateSize();
4232                 }
4233             }
4234         }
4235 
4236         //
4237         // TreeModelListener
4238         //
4239         public void treeNodesChanged(TreeModelEvent e) {
4240             if(treeState != null && e != null) {
4241                 TreePath parentPath = SwingUtilities2.getTreePath(e, getModel());
4242                 int[] indices = e.getChildIndices();
4243                 if (indices == null || indices.length == 0) {
4244                     // The root has changed
4245                     treeState.treeNodesChanged(e);
4246                     updateSize();
4247                 }
4248                 else if (treeState.isExpanded(parentPath)) {
4249                     // Changed nodes are visible
4250                     // Find the minimum index, we only need paint from there
4251                     // down.
4252                     int minIndex = indices[0];
4253                     for (int i = indices.length - 1; i > 0; i--) {
4254                         minIndex = Math.min(indices[i], minIndex);
4255                     }
4256                     Object minChild = treeModel.getChild(
4257                             parentPath.getLastPathComponent(), minIndex);
4258                     TreePath minPath = parentPath.pathByAddingChild(minChild);
4259                     Rectangle minBounds = getPathBounds(tree, minPath);
4260 
4261                     // Forward to the treestate
4262                     treeState.treeNodesChanged(e);
4263 
4264                     // Mark preferred size as bogus.
4265                     updateSize0();
4266 
4267                     // And repaint
4268                     Rectangle newMinBounds = getPathBounds(tree, minPath);
4269                     if (minBounds == null || newMinBounds == null) {
4270                         return;
4271                     }
4272 
4273                     if (indices.length == 1 &&
4274                             newMinBounds.height == minBounds.height) {
4275                         tree.repaint(0, minBounds.y, tree.getWidth(),
4276                                      minBounds.height);
4277                     }
4278                     else {
4279                         tree.repaint(0, minBounds.y, tree.getWidth(),
4280                                      tree.getHeight() - minBounds.y);
4281                     }
4282                 }
4283                 else {
4284                     // Nodes that changed aren't visible.  No need to paint
4285                     treeState.treeNodesChanged(e);
4286                 }
4287             }
4288         }
4289 
4290         public void treeNodesInserted(TreeModelEvent e) {
4291             if(treeState != null && e != null) {
4292                 treeState.treeNodesInserted(e);
4293 
4294                 updateLeadSelectionRow();
4295 
4296                 TreePath       path = SwingUtilities2.getTreePath(e, getModel());
4297 
4298                 if(treeState.isExpanded(path)) {
4299                     updateSize();
4300                 }
4301                 else {
4302                     // PENDING(sky): Need a method in TreeModelEvent
4303                     // that can return the count, getChildIndices allocs
4304                     // a new array!
4305                     int[]      indices = e.getChildIndices();
4306                     int        childCount = treeModel.getChildCount
4307                                             (path.getLastPathComponent());
4308 
4309                     if(indices != null && (childCount - indices.length) == 0)
4310                         updateSize();
4311                 }
4312             }
4313         }
4314 
4315         public void treeNodesRemoved(TreeModelEvent e) {
4316             if(treeState != null && e != null) {
4317                 treeState.treeNodesRemoved(e);
4318 
4319                 updateLeadSelectionRow();
4320 
4321                 TreePath       path = SwingUtilities2.getTreePath(e, getModel());
4322 
4323                 if(treeState.isExpanded(path) ||
4324                    treeModel.getChildCount(path.getLastPathComponent()) == 0)
4325                     updateSize();
4326             }
4327         }
4328 
4329         public void treeStructureChanged(TreeModelEvent e) {
4330             if(treeState != null && e != null) {
4331                 treeState.treeStructureChanged(e);
4332 
4333                 updateLeadSelectionRow();
4334 
4335                 TreePath       pPath = SwingUtilities2.getTreePath(e, getModel());
4336 
4337                 if (pPath != null) {
4338                     pPath = pPath.getParentPath();
4339                 }
4340                 if(pPath == null || treeState.isExpanded(pPath))
4341                     updateSize();
4342             }
4343         }
4344     }
4345 
4346 
4347 
4348     private static class Actions extends UIAction {
4349         private static final String SELECT_PREVIOUS = "selectPrevious";
4350         private static final String SELECT_PREVIOUS_CHANGE_LEAD =
4351                              "selectPreviousChangeLead";
4352         private static final String SELECT_PREVIOUS_EXTEND_SELECTION =
4353                              "selectPreviousExtendSelection";
4354         private static final String SELECT_NEXT = "selectNext";
4355         private static final String SELECT_NEXT_CHANGE_LEAD =
4356                                     "selectNextChangeLead";
4357         private static final String SELECT_NEXT_EXTEND_SELECTION =
4358                                     "selectNextExtendSelection";
4359         private static final String SELECT_CHILD = "selectChild";
4360         private static final String SELECT_CHILD_CHANGE_LEAD =
4361                                     "selectChildChangeLead";
4362         private static final String SELECT_PARENT = "selectParent";
4363         private static final String SELECT_PARENT_CHANGE_LEAD =
4364                                     "selectParentChangeLead";
4365         private static final String SCROLL_UP_CHANGE_SELECTION =
4366                                     "scrollUpChangeSelection";
4367         private static final String SCROLL_UP_CHANGE_LEAD =
4368                                     "scrollUpChangeLead";
4369         private static final String SCROLL_UP_EXTEND_SELECTION =
4370                                     "scrollUpExtendSelection";
4371         private static final String SCROLL_DOWN_CHANGE_SELECTION =
4372                                     "scrollDownChangeSelection";
4373         private static final String SCROLL_DOWN_EXTEND_SELECTION =
4374                                     "scrollDownExtendSelection";
4375         private static final String SCROLL_DOWN_CHANGE_LEAD =
4376                                     "scrollDownChangeLead";
4377         private static final String SELECT_FIRST = "selectFirst";
4378         private static final String SELECT_FIRST_CHANGE_LEAD =
4379                                     "selectFirstChangeLead";
4380         private static final String SELECT_FIRST_EXTEND_SELECTION =
4381                                     "selectFirstExtendSelection";
4382         private static final String SELECT_LAST = "selectLast";
4383         private static final String SELECT_LAST_CHANGE_LEAD =
4384                                     "selectLastChangeLead";
4385         private static final String SELECT_LAST_EXTEND_SELECTION =
4386                                     "selectLastExtendSelection";
4387         private static final String TOGGLE = "toggle";
4388         private static final String CANCEL_EDITING = "cancel";
4389         private static final String START_EDITING = "startEditing";
4390         private static final String SELECT_ALL = "selectAll";
4391         private static final String CLEAR_SELECTION = "clearSelection";
4392         private static final String SCROLL_LEFT = "scrollLeft";
4393         private static final String SCROLL_RIGHT = "scrollRight";
4394         private static final String SCROLL_LEFT_EXTEND_SELECTION =
4395                                     "scrollLeftExtendSelection";
4396         private static final String SCROLL_RIGHT_EXTEND_SELECTION =
4397                                     "scrollRightExtendSelection";
4398         private static final String SCROLL_RIGHT_CHANGE_LEAD =
4399                                     "scrollRightChangeLead";
4400         private static final String SCROLL_LEFT_CHANGE_LEAD =
4401                                     "scrollLeftChangeLead";
4402         private static final String EXPAND = "expand";
4403         private static final String COLLAPSE = "collapse";
4404         private static final String MOVE_SELECTION_TO_PARENT =
4405                                     "moveSelectionToParent";
4406 
4407         // add the lead item to the selection without changing lead or anchor
4408         private static final String ADD_TO_SELECTION = "addToSelection";
4409 
4410         // toggle the selected state of the lead item and move the anchor to it
4411         private static final String TOGGLE_AND_ANCHOR = "toggleAndAnchor";
4412 
4413         // extend the selection to the lead item
4414         private static final String EXTEND_TO = "extendTo";
4415 
4416         // move the anchor to the lead and ensure only that item is selected
4417         private static final String MOVE_SELECTION_TO = "moveSelectionTo";
4418 
4419         Actions() {
4420             super(null);
4421         }
4422 
4423         Actions(String key) {
4424             super(key);
4425         }
4426 
4427         @Override
4428         public boolean accept(Object o) {
4429             if (o instanceof JTree) {
4430                 if (getName() == CANCEL_EDITING) {
4431                     return ((JTree)o).isEditing();
4432                 }
4433             }
4434             return true;
4435         }
4436 
4437         public void actionPerformed(ActionEvent e) {
4438             JTree tree = (JTree)e.getSource();
4439             BasicTreeUI ui = (BasicTreeUI)BasicLookAndFeel.getUIOfType(
4440                              tree.getUI(), BasicTreeUI.class);
4441             if (ui == null) {
4442                 return;
4443             }
4444             String key = getName();
4445             if (key == SELECT_PREVIOUS) {
4446                 increment(tree, ui, -1, false, true);
4447             }
4448             else if (key == SELECT_PREVIOUS_CHANGE_LEAD) {
4449                 increment(tree, ui, -1, false, false);
4450             }
4451             else if (key == SELECT_PREVIOUS_EXTEND_SELECTION) {
4452                 increment(tree, ui, -1, true, true);
4453             }
4454             else if (key == SELECT_NEXT) {
4455                 increment(tree, ui, 1, false, true);
4456             }
4457             else if (key == SELECT_NEXT_CHANGE_LEAD) {
4458                 increment(tree, ui, 1, false, false);
4459             }
4460             else if (key == SELECT_NEXT_EXTEND_SELECTION) {
4461                 increment(tree, ui, 1, true, true);
4462             }
4463             else if (key == SELECT_CHILD) {
4464                 traverse(tree, ui, 1, true);
4465             }
4466             else if (key == SELECT_CHILD_CHANGE_LEAD) {
4467                 traverse(tree, ui, 1, false);
4468             }
4469             else if (key == SELECT_PARENT) {
4470                 traverse(tree, ui, -1, true);
4471             }
4472             else if (key == SELECT_PARENT_CHANGE_LEAD) {
4473                 traverse(tree, ui, -1, false);
4474             }
4475             else if (key == SCROLL_UP_CHANGE_SELECTION) {
4476                 page(tree, ui, -1, false, true);
4477             }
4478             else if (key == SCROLL_UP_CHANGE_LEAD) {
4479                 page(tree, ui, -1, false, false);
4480             }
4481             else if (key == SCROLL_UP_EXTEND_SELECTION) {
4482                 page(tree, ui, -1, true, true);
4483             }
4484             else if (key == SCROLL_DOWN_CHANGE_SELECTION) {
4485                 page(tree, ui, 1, false, true);
4486             }
4487             else if (key == SCROLL_DOWN_EXTEND_SELECTION) {
4488                 page(tree, ui, 1, true, true);
4489             }
4490             else if (key == SCROLL_DOWN_CHANGE_LEAD) {
4491                 page(tree, ui, 1, false, false);
4492             }
4493             else if (key == SELECT_FIRST) {
4494                 home(tree, ui, -1, false, true);
4495             }
4496             else if (key == SELECT_FIRST_CHANGE_LEAD) {
4497                 home(tree, ui, -1, false, false);
4498             }
4499             else if (key == SELECT_FIRST_EXTEND_SELECTION) {
4500                 home(tree, ui, -1, true, true);
4501             }
4502             else if (key == SELECT_LAST) {
4503                 home(tree, ui, 1, false, true);
4504             }
4505             else if (key == SELECT_LAST_CHANGE_LEAD) {
4506                 home(tree, ui, 1, false, false);
4507             }
4508             else if (key == SELECT_LAST_EXTEND_SELECTION) {
4509                 home(tree, ui, 1, true, true);
4510             }
4511             else if (key == TOGGLE) {
4512                 toggle(tree, ui);
4513             }
4514             else if (key == CANCEL_EDITING) {
4515                 cancelEditing(tree, ui);
4516             }
4517             else if (key == START_EDITING) {
4518                 startEditing(tree, ui);
4519             }
4520             else if (key == SELECT_ALL) {
4521                 selectAll(tree, ui, true);
4522             }
4523             else if (key == CLEAR_SELECTION) {
4524                 selectAll(tree, ui, false);
4525             }
4526             else if (key == ADD_TO_SELECTION) {
4527                 if (ui.getRowCount(tree) > 0) {
4528                     int lead = ui.getLeadSelectionRow();
4529                     if (!tree.isRowSelected(lead)) {
4530                         TreePath aPath = ui.getAnchorSelectionPath();
4531                         tree.addSelectionRow(lead);
4532                         ui.setAnchorSelectionPath(aPath);
4533                     }
4534                 }
4535             }
4536             else if (key == TOGGLE_AND_ANCHOR) {
4537                 if (ui.getRowCount(tree) > 0) {
4538                     int lead = ui.getLeadSelectionRow();
4539                     TreePath lPath = ui.getLeadSelectionPath();
4540                     if (!tree.isRowSelected(lead)) {
4541                         tree.addSelectionRow(lead);
4542                     } else {
4543                         tree.removeSelectionRow(lead);
4544                         ui.setLeadSelectionPath(lPath);
4545                     }
4546                     ui.setAnchorSelectionPath(lPath);
4547                 }
4548             }
4549             else if (key == EXTEND_TO) {
4550                 extendSelection(tree, ui);
4551             }
4552             else if (key == MOVE_SELECTION_TO) {
4553                 if (ui.getRowCount(tree) > 0) {
4554                     int lead = ui.getLeadSelectionRow();
4555                     tree.setSelectionInterval(lead, lead);
4556                 }
4557             }
4558             else if (key == SCROLL_LEFT) {
4559                 scroll(tree, ui, SwingConstants.HORIZONTAL, -10);
4560             }
4561             else if (key == SCROLL_RIGHT) {
4562                 scroll(tree, ui, SwingConstants.HORIZONTAL, 10);
4563             }
4564             else if (key == SCROLL_LEFT_EXTEND_SELECTION) {
4565                 scrollChangeSelection(tree, ui, -1, true, true);
4566             }
4567             else if (key == SCROLL_RIGHT_EXTEND_SELECTION) {
4568                 scrollChangeSelection(tree, ui, 1, true, true);
4569             }
4570             else if (key == SCROLL_RIGHT_CHANGE_LEAD) {
4571                 scrollChangeSelection(tree, ui, 1, false, false);
4572             }
4573             else if (key == SCROLL_LEFT_CHANGE_LEAD) {
4574                 scrollChangeSelection(tree, ui, -1, false, false);
4575             }
4576             else if (key == EXPAND) {
4577                 expand(tree, ui);
4578             }
4579             else if (key == COLLAPSE) {
4580                 collapse(tree, ui);
4581             }
4582             else if (key == MOVE_SELECTION_TO_PARENT) {
4583                 moveSelectionToParent(tree, ui);
4584             }
4585         }
4586 
4587         private void scrollChangeSelection(JTree tree, BasicTreeUI ui,
4588                            int direction, boolean addToSelection,
4589                            boolean changeSelection) {
4590             int           rowCount;
4591 
4592             if((rowCount = ui.getRowCount(tree)) > 0 &&
4593                 ui.treeSelectionModel != null) {
4594                 TreePath          newPath;
4595                 Rectangle         visRect = tree.getVisibleRect();
4596 
4597                 if (direction == -1) {
4598                     newPath = ui.getClosestPathForLocation(tree, visRect.x,
4599                                                         visRect.y);
4600                     visRect.x = Math.max(0, visRect.x - visRect.width);
4601                 }
4602                 else {
4603                     visRect.x = Math.min(Math.max(0, tree.getWidth() -
4604                                    visRect.width), visRect.x + visRect.width);
4605                     newPath = ui.getClosestPathForLocation(tree, visRect.x,
4606                                                  visRect.y + visRect.height);
4607                 }
4608                 // Scroll
4609                 tree.scrollRectToVisible(visRect);
4610                 // select
4611                 if (addToSelection) {
4612                     ui.extendSelection(newPath);
4613                 }
4614                 else if(changeSelection) {
4615                     tree.setSelectionPath(newPath);
4616                 }
4617                 else {
4618                     ui.setLeadSelectionPath(newPath, true);
4619                 }
4620             }
4621         }
4622 
4623         private void scroll(JTree component, BasicTreeUI ui, int direction,
4624                             int amount) {
4625             Rectangle visRect = component.getVisibleRect();
4626             Dimension size = component.getSize();
4627             if (direction == SwingConstants.HORIZONTAL) {
4628                 visRect.x += amount;
4629                 visRect.x = Math.max(0, visRect.x);
4630                 visRect.x = Math.min(Math.max(0, size.width - visRect.width),
4631                                      visRect.x);
4632             }
4633             else {
4634                 visRect.y += amount;
4635                 visRect.y = Math.max(0, visRect.y);
4636                 visRect.y = Math.min(Math.max(0, size.width - visRect.height),
4637                                      visRect.y);
4638             }
4639             component.scrollRectToVisible(visRect);
4640         }
4641 
4642         private void extendSelection(JTree tree, BasicTreeUI ui) {
4643             if (ui.getRowCount(tree) > 0) {
4644                 int       lead = ui.getLeadSelectionRow();
4645 
4646                 if (lead != -1) {
4647                     TreePath      leadP = ui.getLeadSelectionPath();
4648                     TreePath      aPath = ui.getAnchorSelectionPath();
4649                     int           aRow = ui.getRowForPath(tree, aPath);
4650 
4651                     if(aRow == -1)
4652                         aRow = 0;
4653                     tree.setSelectionInterval(aRow, lead);
4654                     ui.setLeadSelectionPath(leadP);
4655                     ui.setAnchorSelectionPath(aPath);
4656                 }
4657             }
4658         }
4659 
4660         private void selectAll(JTree tree, BasicTreeUI ui, boolean selectAll) {
4661             int                   rowCount = ui.getRowCount(tree);
4662 
4663             if(rowCount > 0) {
4664                 if(selectAll) {
4665                     if (tree.getSelectionModel().getSelectionMode() ==
4666                             TreeSelectionModel.SINGLE_TREE_SELECTION) {
4667 
4668                         int lead = ui.getLeadSelectionRow();
4669                         if (lead != -1) {
4670                             tree.setSelectionRow(lead);
4671                         } else if (tree.getMinSelectionRow() == -1) {
4672                             tree.setSelectionRow(0);
4673                             ui.ensureRowsAreVisible(0, 0);
4674                         }
4675                         return;
4676                     }
4677 
4678                     TreePath      lastPath = ui.getLeadSelectionPath();
4679                     TreePath      aPath = ui.getAnchorSelectionPath();
4680 
4681                     if(lastPath != null && !tree.isVisible(lastPath)) {
4682                         lastPath = null;
4683                     }
4684                     tree.setSelectionInterval(0, rowCount - 1);
4685                     if(lastPath != null) {
4686                         ui.setLeadSelectionPath(lastPath);
4687                     }
4688                     if(aPath != null && tree.isVisible(aPath)) {
4689                         ui.setAnchorSelectionPath(aPath);
4690                     }
4691                 }
4692                 else {
4693                     TreePath      lastPath = ui.getLeadSelectionPath();
4694                     TreePath      aPath = ui.getAnchorSelectionPath();
4695 
4696                     tree.clearSelection();
4697                     ui.setAnchorSelectionPath(aPath);
4698                     ui.setLeadSelectionPath(lastPath);
4699                 }
4700             }
4701         }
4702 
4703         private void startEditing(JTree tree, BasicTreeUI ui) {
4704             TreePath   lead = ui.getLeadSelectionPath();
4705             int        editRow = (lead != null) ?
4706                                      ui.getRowForPath(tree, lead) : -1;
4707 
4708             if(editRow != -1) {
4709                 tree.startEditingAtPath(lead);
4710             }
4711         }
4712 
4713         private void cancelEditing(JTree tree, BasicTreeUI ui) {
4714             tree.cancelEditing();
4715         }
4716 
4717         private void toggle(JTree tree, BasicTreeUI ui) {
4718             int            selRow = ui.getLeadSelectionRow();
4719 
4720             if(selRow != -1 && !ui.isLeaf(selRow)) {
4721                 TreePath aPath = ui.getAnchorSelectionPath();
4722                 TreePath lPath = ui.getLeadSelectionPath();
4723 
4724                 ui.toggleExpandState(ui.getPathForRow(tree, selRow));
4725                 ui.setAnchorSelectionPath(aPath);
4726                 ui.setLeadSelectionPath(lPath);
4727             }
4728         }
4729 
4730         private void expand(JTree tree, BasicTreeUI ui) {
4731             int selRow = ui.getLeadSelectionRow();
4732             tree.expandRow(selRow);
4733         }
4734 
4735         private void collapse(JTree tree, BasicTreeUI ui) {
4736             int selRow = ui.getLeadSelectionRow();
4737             tree.collapseRow(selRow);
4738         }
4739 
4740         private void increment(JTree tree, BasicTreeUI ui, int direction,
4741                                boolean addToSelection,
4742                                boolean changeSelection) {
4743 
4744             // disable moving of lead unless in discontiguous mode
4745             if (!addToSelection && !changeSelection &&
4746                     tree.getSelectionModel().getSelectionMode() !=
4747                         TreeSelectionModel.DISCONTIGUOUS_TREE_SELECTION) {
4748                 changeSelection = true;
4749             }
4750 
4751             int              rowCount;
4752 
4753             if(ui.treeSelectionModel != null &&
4754                   (rowCount = tree.getRowCount()) > 0) {
4755                 int                  selIndex = ui.getLeadSelectionRow();
4756                 int                  newIndex;
4757 
4758                 if(selIndex == -1) {
4759                     if(direction == 1)
4760                         newIndex = 0;
4761                     else
4762                         newIndex = rowCount - 1;
4763                 }
4764                 else
4765                     /* Aparently people don't like wrapping;( */
4766                     newIndex = Math.min(rowCount - 1, Math.max
4767                                         (0, (selIndex + direction)));
4768                 if(addToSelection && ui.treeSelectionModel.
4769                         getSelectionMode() != TreeSelectionModel.
4770                         SINGLE_TREE_SELECTION) {
4771                     ui.extendSelection(tree.getPathForRow(newIndex));
4772                 }
4773                 else if(changeSelection) {
4774                     tree.setSelectionInterval(newIndex, newIndex);
4775                 }
4776                 else {
4777                     ui.setLeadSelectionPath(tree.getPathForRow(newIndex),true);
4778                 }
4779                 ui.ensureRowsAreVisible(newIndex, newIndex);
4780                 ui.lastSelectedRow = newIndex;
4781             }
4782         }
4783 
4784         private void traverse(JTree tree, BasicTreeUI ui, int direction,
4785                               boolean changeSelection) {
4786 
4787             // disable moving of lead unless in discontiguous mode
4788             if (!changeSelection &&
4789                     tree.getSelectionModel().getSelectionMode() !=
4790                         TreeSelectionModel.DISCONTIGUOUS_TREE_SELECTION) {
4791                 changeSelection = true;
4792             }
4793 
4794             int                rowCount;
4795 
4796             if((rowCount = tree.getRowCount()) > 0) {
4797                 int               minSelIndex = ui.getLeadSelectionRow();
4798                 int               newIndex;
4799 
4800                 if(minSelIndex == -1)
4801                     newIndex = 0;
4802                 else {
4803                     /* Try and expand the node, otherwise go to next
4804                        node. */
4805                     if(direction == 1) {
4806                         TreePath minSelPath = ui.getPathForRow(tree, minSelIndex);
4807                         int childCount = tree.getModel().
4808                             getChildCount(minSelPath.getLastPathComponent());
4809                         newIndex = -1;
4810                         if (!ui.isLeaf(minSelIndex)) {
4811                             if (!tree.isExpanded(minSelIndex)) {
4812                                 ui.toggleExpandState(minSelPath);
4813                             }
4814                             else if (childCount > 0) {
4815                                 newIndex = Math.min(minSelIndex + 1, rowCount - 1);
4816                             }
4817                         }
4818                     }
4819                     /* Try to collapse node. */
4820                     else {
4821                         if(!ui.isLeaf(minSelIndex) &&
4822                            tree.isExpanded(minSelIndex)) {
4823                             ui.toggleExpandState(ui.getPathForRow
4824                                               (tree, minSelIndex));
4825                             newIndex = -1;
4826                         }
4827                         else {
4828                             TreePath         path = ui.getPathForRow(tree,
4829                                                                   minSelIndex);
4830 
4831                             if(path != null && path.getPathCount() > 1) {
4832                                 newIndex = ui.getRowForPath(tree, path.
4833                                                          getParentPath());
4834                             }
4835                             else
4836                                 newIndex = -1;
4837                         }
4838                     }
4839                 }
4840                 if(newIndex != -1) {
4841                     if(changeSelection) {
4842                         tree.setSelectionInterval(newIndex, newIndex);
4843                     }
4844                     else {
4845                         ui.setLeadSelectionPath(ui.getPathForRow(
4846                                                     tree, newIndex), true);
4847                     }
4848                     ui.ensureRowsAreVisible(newIndex, newIndex);
4849                 }
4850             }
4851         }
4852 
4853         private void moveSelectionToParent(JTree tree, BasicTreeUI ui) {
4854             int selRow = ui.getLeadSelectionRow();
4855             TreePath path = ui.getPathForRow(tree, selRow);
4856             if (path != null && path.getPathCount() > 1) {
4857                 int  newIndex = ui.getRowForPath(tree, path.getParentPath());
4858                 if (newIndex != -1) {
4859                     tree.setSelectionInterval(newIndex, newIndex);
4860                     ui.ensureRowsAreVisible(newIndex, newIndex);
4861                 }
4862             }
4863         }
4864 
4865         private void page(JTree tree, BasicTreeUI ui, int direction,
4866                           boolean addToSelection, boolean changeSelection) {
4867 
4868             // disable moving of lead unless in discontiguous mode
4869             if (!addToSelection && !changeSelection &&
4870                     tree.getSelectionModel().getSelectionMode() !=
4871                         TreeSelectionModel.DISCONTIGUOUS_TREE_SELECTION) {
4872                 changeSelection = true;
4873             }
4874 
4875             int           rowCount;
4876 
4877             if((rowCount = ui.getRowCount(tree)) > 0 &&
4878                            ui.treeSelectionModel != null) {
4879                 Dimension         maxSize = tree.getSize();
4880                 TreePath          lead = ui.getLeadSelectionPath();
4881                 TreePath          newPath;
4882                 Rectangle         visRect = tree.getVisibleRect();
4883 
4884                 if(direction == -1) {
4885                     // up.
4886                     newPath = ui.getClosestPathForLocation(tree, visRect.x,
4887                                                          visRect.y);
4888                     if(newPath.equals(lead)) {
4889                         visRect.y = Math.max(0, visRect.y - visRect.height);
4890                         newPath = tree.getClosestPathForLocation(visRect.x,
4891                                                                  visRect.y);
4892                     }
4893                 }
4894                 else {
4895                     // down
4896                     visRect.y = Math.min(maxSize.height, visRect.y +
4897                                          visRect.height - 1);
4898                     newPath = tree.getClosestPathForLocation(visRect.x,
4899                                                              visRect.y);
4900                     if(newPath.equals(lead)) {
4901                         visRect.y = Math.min(maxSize.height, visRect.y +
4902                                              visRect.height - 1);
4903                         newPath = tree.getClosestPathForLocation(visRect.x,
4904                                                                  visRect.y);
4905                     }
4906                 }
4907                 Rectangle            newRect = ui.getPathBounds(tree, newPath);
4908                 if (newRect != null) {
4909                     newRect.x = visRect.x;
4910                     newRect.width = visRect.width;
4911                     if(direction == -1) {
4912                         newRect.height = visRect.height;
4913                     }
4914                     else {
4915                         newRect.y -= (visRect.height - newRect.height);
4916                         newRect.height = visRect.height;
4917                     }
4918 
4919                     if(addToSelection) {
4920                         ui.extendSelection(newPath);
4921                     }
4922                     else if(changeSelection) {
4923                         tree.setSelectionPath(newPath);
4924                     }
4925                     else {
4926                         ui.setLeadSelectionPath(newPath, true);
4927                     }
4928                     tree.scrollRectToVisible(newRect);
4929                 }
4930             }
4931         }
4932 
4933         private void home(JTree tree, final BasicTreeUI ui, int direction,
4934                           boolean addToSelection, boolean changeSelection) {
4935 
4936             // disable moving of lead unless in discontiguous mode
4937             if (!addToSelection && !changeSelection &&
4938                     tree.getSelectionModel().getSelectionMode() !=
4939                         TreeSelectionModel.DISCONTIGUOUS_TREE_SELECTION) {
4940                 changeSelection = true;
4941             }
4942 
4943             final int rowCount = ui.getRowCount(tree);
4944 
4945             if (rowCount > 0) {
4946                 if(direction == -1) {
4947                     ui.ensureRowsAreVisible(0, 0);
4948                     if (addToSelection) {
4949                         TreePath        aPath = ui.getAnchorSelectionPath();
4950                         int             aRow = (aPath == null) ? -1 :
4951                                         ui.getRowForPath(tree, aPath);
4952 
4953                         if (aRow == -1) {
4954                             tree.setSelectionInterval(0, 0);
4955                         }
4956                         else {
4957                             tree.setSelectionInterval(0, aRow);
4958                             ui.setAnchorSelectionPath(aPath);
4959                             ui.setLeadSelectionPath(ui.getPathForRow(tree, 0));
4960                         }
4961                     }
4962                     else if(changeSelection) {
4963                         tree.setSelectionInterval(0, 0);
4964                     }
4965                     else {
4966                         ui.setLeadSelectionPath(ui.getPathForRow(tree, 0),
4967                                                 true);
4968                     }
4969                 }
4970                 else {
4971                     ui.ensureRowsAreVisible(rowCount - 1, rowCount - 1);
4972                     if (addToSelection) {
4973                         TreePath        aPath = ui.getAnchorSelectionPath();
4974                         int             aRow = (aPath == null) ? -1 :
4975                                         ui.getRowForPath(tree, aPath);
4976 
4977                         if (aRow == -1) {
4978                             tree.setSelectionInterval(rowCount - 1,
4979                                                       rowCount -1);
4980                         }
4981                         else {
4982                             tree.setSelectionInterval(aRow, rowCount - 1);
4983                             ui.setAnchorSelectionPath(aPath);
4984                             ui.setLeadSelectionPath(ui.getPathForRow(tree,
4985                                                                rowCount -1));
4986                         }
4987                     }
4988                     else if(changeSelection) {
4989                         tree.setSelectionInterval(rowCount - 1, rowCount - 1);
4990                     }
4991                     else {
4992                         ui.setLeadSelectionPath(ui.getPathForRow(tree,
4993                                                           rowCount - 1), true);
4994                     }
4995                     if (ui.isLargeModel()){
4996                         SwingUtilities.invokeLater(new Runnable() {
4997                             public void run() {
4998                                 ui.ensureRowsAreVisible(rowCount - 1, rowCount - 1);
4999                             }
5000                         });
5001                     }
5002                 }
5003             }
5004         }
5005     }
5006 } // End of class BasicTreeUI