1 /*
   2  * Copyright (c) 1997, 2014, 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.table;
  27 
  28 import sun.swing.table.DefaultTableCellHeaderRenderer;
  29 
  30 import java.util.*;
  31 import java.awt.*;
  32 import java.awt.event.*;
  33 
  34 import javax.swing.*;
  35 import javax.swing.event.*;
  36 import javax.swing.plaf.*;
  37 import javax.accessibility.*;
  38 
  39 import java.beans.PropertyChangeListener;
  40 import java.beans.Transient;
  41 
  42 import java.io.ObjectOutputStream;
  43 import java.io.ObjectInputStream;
  44 import java.io.IOException;
  45 
  46 
  47 /**
  48  * This is the object which manages the header of the <code>JTable</code>.
  49  * <p>
  50  * <strong>Warning:</strong>
  51  * Serialized objects of this class will not be compatible with
  52  * future Swing releases. The current serialization support is
  53  * appropriate for short term storage or RMI between applications running
  54  * the same version of Swing.  As of 1.4, support for long term storage
  55  * of all JavaBeans&trade;
  56  * has been added to the <code>java.beans</code> package.
  57  * Please see {@link java.beans.XMLEncoder}.
  58  *
  59  * @author Alan Chung
  60  * @author Philip Milne
  61  * @see javax.swing.JTable
  62  */
  63 @SuppressWarnings("serial") // Same-version serialization only
  64 public class JTableHeader extends JComponent implements TableColumnModelListener, Accessible
  65 {
  66     /**
  67      * @see #getUIClassID
  68      * @see #readObject
  69      */
  70     private static final String uiClassID = "TableHeaderUI";
  71 
  72 //
  73 // Instance Variables
  74 //
  75     /**
  76      * The table for which this object is the header;
  77      * the default is <code>null</code>.
  78      */
  79     protected JTable table;
  80 
  81     /**
  82      * The <code>TableColumnModel</code> of the table header.
  83      */
  84     protected TableColumnModel  columnModel;
  85 
  86     /**
  87      * If true, reordering of columns are allowed by the user;
  88      * the default is true.
  89      */
  90     protected boolean   reorderingAllowed;
  91 
  92     /**
  93      * If true, resizing of columns are allowed by the user;
  94      * the default is true.
  95      */
  96     protected boolean   resizingAllowed;
  97 
  98     /**
  99      * Obsolete as of Java 2 platform v1.3.  Real time repaints, in response
 100      * to column dragging or resizing, are now unconditional.
 101      */
 102     /*
 103      * If this flag is true, then the header will repaint the table as
 104      * a column is dragged or resized; the default is true.
 105      */
 106     protected boolean   updateTableInRealTime;
 107 
 108     /** The index of the column being resized. <code>null</code> if not resizing. */
 109     transient protected TableColumn     resizingColumn;
 110 
 111     /** The index of the column being dragged. <code>null</code> if not dragging. */
 112     transient protected TableColumn     draggedColumn;
 113 
 114     /** The distance from its original position the column has been dragged. */
 115     transient protected int     draggedDistance;
 116 
 117     /**
 118       *  The default renderer to be used when a <code>TableColumn</code>
 119       *  does not define a <code>headerRenderer</code>.
 120       */
 121     private TableCellRenderer defaultRenderer;
 122 
 123 //
 124 // Constructors
 125 //
 126 
 127     /**
 128      *  Constructs a <code>JTableHeader</code> with a default
 129      *  <code>TableColumnModel</code>.
 130      *
 131      * @see #createDefaultColumnModel
 132      */
 133     public JTableHeader() {
 134         this(null);
 135     }
 136 
 137     /**
 138      *  Constructs a <code>JTableHeader</code> which is initialized with
 139      *  <code>cm</code> as the column model.  If <code>cm</code> is
 140      *  <code>null</code> this method will initialize the table header
 141      *  with a default <code>TableColumnModel</code>.
 142      *
 143      * @param cm        the column model for the table
 144      * @see #createDefaultColumnModel
 145      */
 146     public JTableHeader(TableColumnModel cm) {
 147         super();
 148 
 149         //setFocusable(false); // for strict win/mac compatibility mode,
 150                                // this method should be invoked
 151 
 152         if (cm == null)
 153             cm = createDefaultColumnModel();
 154         setColumnModel(cm);
 155 
 156         // Initialize local ivars
 157         initializeLocalVars();
 158 
 159         // Get UI going
 160         updateUI();
 161     }
 162 
 163 //
 164 // Local behavior attributes
 165 //
 166 
 167     /**
 168      *  Sets the table associated with this header.
 169      *  @param  table   the new table
 170      *  @beaninfo
 171      *   bound: true
 172      *   description: The table associated with this header.
 173      */
 174     public void setTable(JTable table) {
 175         JTable old = this.table;
 176         this.table = table;
 177         firePropertyChange("table", old, table);
 178     }
 179 
 180     /**
 181       *  Returns the table associated with this header.
 182       *  @return  the <code>table</code> property
 183       */
 184     public JTable getTable() {
 185         return table;
 186     }
 187 
 188     /**
 189      *  Sets whether the user can drag column headers to reorder columns.
 190      *
 191      * @param   reorderingAllowed       true if the table view should allow
 192      *                                  reordering; otherwise false
 193      * @see     #getReorderingAllowed
 194      * @beaninfo
 195      *  bound: true
 196      *  description: Whether the user can drag column headers to reorder columns.
 197      */
 198     public void setReorderingAllowed(boolean reorderingAllowed) {
 199         boolean old = this.reorderingAllowed;
 200         this.reorderingAllowed = reorderingAllowed;
 201         firePropertyChange("reorderingAllowed", old, reorderingAllowed);
 202     }
 203 
 204     /**
 205      * Returns true if the user is allowed to rearrange columns by
 206      * dragging their headers, false otherwise. The default is true. You can
 207      * rearrange columns programmatically regardless of this setting.
 208      *
 209      * @return  the <code>reorderingAllowed</code> property
 210      * @see     #setReorderingAllowed
 211      */
 212     public boolean getReorderingAllowed() {
 213         return reorderingAllowed;
 214     }
 215 
 216     /**
 217      *  Sets whether the user can resize columns by dragging between headers.
 218      *
 219      * @param   resizingAllowed         true if table view should allow
 220      *                                  resizing
 221      * @see     #getResizingAllowed
 222      * @beaninfo
 223      *  bound: true
 224      *  description: Whether the user can resize columns by dragging between headers.
 225      */
 226     public void setResizingAllowed(boolean resizingAllowed) {
 227         boolean old = this.resizingAllowed;
 228         this.resizingAllowed = resizingAllowed;
 229         firePropertyChange("resizingAllowed", old, resizingAllowed);
 230     }
 231 
 232     /**
 233      * Returns true if the user is allowed to resize columns by dragging
 234      * between their headers, false otherwise. The default is true. You can
 235      * resize columns programmatically regardless of this setting.
 236      *
 237      * @return  the <code>resizingAllowed</code> property
 238      * @see     #setResizingAllowed
 239      */
 240     public boolean getResizingAllowed() {
 241         return resizingAllowed;
 242     }
 243 
 244     /**
 245      * Returns the the dragged column, if and only if, a drag is in
 246      * process, otherwise returns <code>null</code>.
 247      *
 248      * @return  the dragged column, if a drag is in
 249      *          process, otherwise returns <code>null</code>
 250      * @see     #getDraggedDistance
 251      */
 252     public TableColumn getDraggedColumn() {
 253         return draggedColumn;
 254     }
 255 
 256     /**
 257      * Returns the column's horizontal distance from its original
 258      * position, if and only if, a drag is in process. Otherwise, the
 259      * the return value is meaningless.
 260      *
 261      * @return  the column's horizontal distance from its original
 262      *          position, if a drag is in process, otherwise the return
 263      *          value is meaningless
 264      * @see     #getDraggedColumn
 265      */
 266     public int getDraggedDistance() {
 267         return draggedDistance;
 268     }
 269 
 270     /**
 271      * Returns the resizing column.  If no column is being
 272      * resized this method returns <code>null</code>.
 273      *
 274      * @return  the resizing column, if a resize is in process, otherwise
 275      *          returns <code>null</code>
 276      */
 277     public TableColumn getResizingColumn() {
 278         return resizingColumn;
 279     }
 280 
 281     /**
 282      * Obsolete as of Java 2 platform v1.3.  Real time repaints, in response to
 283      * column dragging or resizing, are now unconditional.
 284      */
 285     /*
 286      *  Sets whether the body of the table updates in real time when
 287      *  a column is resized or dragged.
 288      *
 289      * @param   flag                    true if tableView should update
 290      *                                  the body of the table in real time
 291      * @see #getUpdateTableInRealTime
 292      */
 293     public void setUpdateTableInRealTime(boolean flag) {
 294         updateTableInRealTime = flag;
 295     }
 296 
 297     /**
 298      * Obsolete as of Java 2 platform v1.3.  Real time repaints, in response to
 299      * column dragging or resizing, are now unconditional.
 300      */
 301     /*
 302      * Returns true if the body of the table view updates in real
 303      * time when a column is resized or dragged.  User can set this flag to
 304      * false to speed up the table's response to user resize or drag actions.
 305      * The default is true.
 306      *
 307      * @return  true if the table updates in real time
 308      * @see #setUpdateTableInRealTime
 309      */
 310     public boolean getUpdateTableInRealTime() {
 311         return updateTableInRealTime;
 312     }
 313 
 314     /**
 315      * Sets the default renderer to be used when no <code>headerRenderer</code>
 316      * is defined by a <code>TableColumn</code>.
 317      * @param  defaultRenderer  the default renderer
 318      * @since 1.3
 319      */
 320     public void setDefaultRenderer(TableCellRenderer defaultRenderer) {
 321         this.defaultRenderer = defaultRenderer;
 322     }
 323 
 324     /**
 325      * Returns the default renderer used when no <code>headerRenderer</code>
 326      * is defined by a <code>TableColumn</code>.
 327      * @return the default renderer
 328      * @since 1.3
 329      */
 330     @Transient
 331     public TableCellRenderer getDefaultRenderer() {
 332         return defaultRenderer;
 333     }
 334 
 335     /**
 336      * Returns the index of the column that <code>point</code> lies in, or -1 if it
 337      * lies out of bounds.
 338      *
 339      * @param point  if this <code>point</code> lies within a column, the index of
 340      *               that column will be returned; otherwise it is out of bounds
 341      *               and -1 is returned
 342      *
 343      * @return  the index of the column that <code>point</code> lies in, or -1 if it
 344      *          lies out of bounds
 345      */
 346     public int columnAtPoint(Point point) {
 347         int x = point.x;
 348         if (!getComponentOrientation().isLeftToRight()) {
 349             x = getWidthInRightToLeft() - x - 1;
 350         }
 351         return getColumnModel().getColumnIndexAtX(x);
 352     }
 353 
 354     /**
 355      * Returns the rectangle containing the header tile at <code>column</code>.
 356      * When the <code>column</code> parameter is out of bounds this method uses the
 357      * same conventions as the <code>JTable</code> method <code>getCellRect</code>.
 358      *
 359      * @param column  index of the column
 360      *
 361      * @return  the rectangle containing the header tile at <code>column</code>
 362      * @see JTable#getCellRect
 363      */
 364     public Rectangle getHeaderRect(int column) {
 365         Rectangle r = new Rectangle();
 366         TableColumnModel cm = getColumnModel();
 367 
 368         r.height = getHeight();
 369 
 370         if (column < 0) {
 371             // x = width = 0;
 372             if( !getComponentOrientation().isLeftToRight() ) {
 373                 r.x = getWidthInRightToLeft();
 374             }
 375         }
 376         else if (column >= cm.getColumnCount()) {
 377             if( getComponentOrientation().isLeftToRight() ) {
 378                 r.x = getWidth();
 379             }
 380         }
 381         else {
 382             for(int i = 0; i < column; i++) {
 383                 r.x += cm.getColumn(i).getWidth();
 384             }
 385             if( !getComponentOrientation().isLeftToRight() ) {
 386                 r.x = getWidthInRightToLeft() - r.x - cm.getColumn(column).getWidth();
 387             }
 388 
 389             r.width = cm.getColumn(column).getWidth();
 390         }
 391         return r;
 392     }
 393 
 394 
 395     /**
 396      * Allows the renderer's tips to be used if there is text set.
 397      * @param  event  the location of the event identifies the proper
 398      *                          renderer and, therefore, the proper tip
 399      * @return the tool tip for this component
 400      */
 401     public String getToolTipText(MouseEvent event) {
 402         String tip = null;
 403         Point p = event.getPoint();
 404         int column;
 405 
 406         // Locate the renderer under the event location
 407         if ((column = columnAtPoint(p)) != -1) {
 408             TableColumn aColumn = columnModel.getColumn(column);
 409             TableCellRenderer renderer = aColumn.getHeaderRenderer();
 410             if (renderer == null) {
 411                 renderer = defaultRenderer;
 412             }
 413             Component component = renderer.getTableCellRendererComponent(
 414                               getTable(), aColumn.getHeaderValue(), false, false,
 415                               -1, column);
 416 
 417             // Now have to see if the component is a JComponent before
 418             // getting the tip
 419             if (component instanceof JComponent) {
 420                 // Convert the event to the renderer's coordinate system
 421                 MouseEvent newEvent;
 422                 Rectangle cellRect = getHeaderRect(column);
 423 
 424                 p.translate(-cellRect.x, -cellRect.y);
 425                 newEvent = new MouseEvent(component, event.getID(),
 426                                           event.getWhen(), event.getModifiers(),
 427                                           p.x, p.y, event.getXOnScreen(), event.getYOnScreen(),
 428                                           event.getClickCount(),
 429                                           event.isPopupTrigger(), MouseEvent.NOBUTTON);
 430 
 431                 tip = ((JComponent)component).getToolTipText(newEvent);
 432             }
 433         }
 434 
 435         // No tip from the renderer get our own tip
 436         if (tip == null)
 437             tip = getToolTipText();
 438 
 439         return tip;
 440     }
 441 
 442 //
 443 // Managing TableHeaderUI
 444 //
 445 
 446     /**
 447      * Returns the look and feel (L&amp;F) object that renders this component.
 448      *
 449      * @return the <code>TableHeaderUI</code> object that renders this component
 450      */
 451     public TableHeaderUI getUI() {
 452         return (TableHeaderUI)ui;
 453     }
 454 
 455     /**
 456      * Sets the look and feel (L&amp;F) object that renders this component.
 457      *
 458      * @param ui  the <code>TableHeaderUI</code> L&amp;F object
 459      * @see UIDefaults#getUI
 460      */
 461     public void setUI(TableHeaderUI ui){
 462         if (this.ui != ui) {
 463             super.setUI(ui);
 464             repaint();
 465         }
 466     }
 467 
 468     /**
 469      * Notification from the <code>UIManager</code> that the look and feel
 470      * (L&amp;F) has changed.
 471      * Replaces the current UI object with the latest version from the
 472      * <code>UIManager</code>.
 473      *
 474      * @see JComponent#updateUI
 475      */
 476     public void updateUI(){
 477         setUI((TableHeaderUI)UIManager.getUI(this));
 478 
 479         TableCellRenderer renderer = getDefaultRenderer();
 480         if (renderer instanceof Component) {
 481             SwingUtilities.updateComponentTreeUI((Component)renderer);
 482         }
 483     }
 484 
 485 
 486     /**
 487      * Returns the suffix used to construct the name of the look and feel
 488      * (L&amp;F) class used to render this component.
 489      * @return the string "TableHeaderUI"
 490      *
 491      * @return "TableHeaderUI"
 492      * @see JComponent#getUIClassID
 493      * @see UIDefaults#getUI
 494      */
 495     public String getUIClassID() {
 496         return uiClassID;
 497     }
 498 
 499 
 500 //
 501 // Managing models
 502 //
 503 
 504 
 505     /**
 506      *  Sets the column model for this table to <code>newModel</code> and registers
 507      *  for listener notifications from the new column model.
 508      *
 509      * @param   columnModel     the new data source for this table
 510      * @exception IllegalArgumentException
 511      *                          if <code>newModel</code> is <code>null</code>
 512      * @see     #getColumnModel
 513      * @beaninfo
 514      *  bound: true
 515      *  description: The object governing the way columns appear in the view.
 516      */
 517     public void setColumnModel(TableColumnModel columnModel) {
 518         if (columnModel == null) {
 519             throw new IllegalArgumentException("Cannot set a null ColumnModel");
 520         }
 521         TableColumnModel old = this.columnModel;
 522         if (columnModel != old) {
 523             if (old != null) {
 524                 old.removeColumnModelListener(this);
 525             }
 526             this.columnModel = columnModel;
 527             columnModel.addColumnModelListener(this);
 528 
 529             firePropertyChange("columnModel", old, columnModel);
 530             resizeAndRepaint();
 531         }
 532     }
 533 
 534     /**
 535      * Returns the <code>TableColumnModel</code> that contains all column information
 536      * of this table header.
 537      *
 538      * @return  the <code>columnModel</code> property
 539      * @see     #setColumnModel
 540      */
 541     public TableColumnModel getColumnModel() {
 542         return columnModel;
 543     }
 544 
 545 //
 546 // Implementing TableColumnModelListener interface
 547 //
 548 
 549     /**
 550      * Invoked when a column is added to the table column model.
 551      * <p>
 552      * Application code will not use these methods explicitly, they
 553      * are used internally by <code>JTable</code>.
 554      *
 555      * @param e  the event received
 556      * @see TableColumnModelListener
 557      */
 558     public void columnAdded(TableColumnModelEvent e) { resizeAndRepaint(); }
 559 
 560 
 561     /**
 562      * Invoked when a column is removed from the table column model.
 563      * <p>
 564      * Application code will not use these methods explicitly, they
 565      * are used internally by <code>JTable</code>.
 566      *
 567      * @param e  the event received
 568      * @see TableColumnModelListener
 569      */
 570     public void columnRemoved(TableColumnModelEvent e) { resizeAndRepaint(); }
 571 
 572 
 573     /**
 574      * Invoked when a column is repositioned.
 575      * <p>
 576      * Application code will not use these methods explicitly, they
 577      * are used internally by <code>JTable</code>.
 578      *
 579      * @param e the event received
 580      * @see TableColumnModelListener
 581      */
 582     public void columnMoved(TableColumnModelEvent e) { repaint(); }
 583 
 584 
 585     /**
 586      * Invoked when a column is moved due to a margin change.
 587      * <p>
 588      * Application code will not use these methods explicitly, they
 589      * are used internally by <code>JTable</code>.
 590      *
 591      * @param e the event received
 592      * @see TableColumnModelListener
 593      */
 594     public void columnMarginChanged(ChangeEvent e) { resizeAndRepaint(); }
 595 
 596 
 597     // --Redrawing the header is slow in cell selection mode.
 598     // --Since header selection is ugly and it is always clear from the
 599     // --view which columns are selected, don't redraw the header.
 600     /**
 601      * Invoked when the selection model of the <code>TableColumnModel</code>
 602      * is changed.  This method currently has no effect (the header is not
 603      * redrawn).
 604      * <p>
 605      * Application code will not use these methods explicitly, they
 606      * are used internally by <code>JTable</code>.
 607      *
 608      * @param e the event received
 609      * @see TableColumnModelListener
 610      */
 611     public void columnSelectionChanged(ListSelectionEvent e) { } // repaint(); }
 612 
 613 //
 614 //  Package Methods
 615 //
 616 
 617     /**
 618      *  Returns the default column model object which is
 619      *  a <code>DefaultTableColumnModel</code>.  A subclass can override this
 620      *  method to return a different column model object
 621      *
 622      * @return the default column model object
 623      */
 624     protected TableColumnModel createDefaultColumnModel() {
 625         return new DefaultTableColumnModel();
 626     }
 627 
 628     /**
 629      *  Returns a default renderer to be used when no header renderer
 630      *  is defined by a <code>TableColumn</code>.
 631      *
 632      *  @return the default table column renderer
 633      * @since 1.3
 634      */
 635     protected TableCellRenderer createDefaultRenderer() {
 636         return new DefaultTableCellHeaderRenderer();
 637     }
 638 
 639 
 640     /**
 641      * Initializes the local variables and properties with default values.
 642      * Used by the constructor methods.
 643      */
 644     protected void initializeLocalVars() {
 645         setOpaque(true);
 646         table = null;
 647         reorderingAllowed = true;
 648         resizingAllowed = true;
 649         draggedColumn = null;
 650         draggedDistance = 0;
 651         resizingColumn = null;
 652         updateTableInRealTime = true;
 653 
 654         // I'm registered to do tool tips so we can draw tips for the
 655         // renderers
 656         ToolTipManager toolTipManager = ToolTipManager.sharedInstance();
 657         toolTipManager.registerComponent(this);
 658         setDefaultRenderer(createDefaultRenderer());
 659     }
 660 
 661     /**
 662      * Sizes the header and marks it as needing display.  Equivalent
 663      * to <code>revalidate</code> followed by <code>repaint</code>.
 664      */
 665     public void resizeAndRepaint() {
 666         revalidate();
 667         repaint();
 668     }
 669 
 670     /**
 671       *  Sets the header's <code>draggedColumn</code> to <code>aColumn</code>.
 672       *  <p>
 673       *  Application code will not use this method explicitly, it is used
 674       *  internally by the column dragging mechanism.
 675       *
 676       *  @param  aColumn  the column being dragged, or <code>null</code> if
 677       *                 no column is being dragged
 678       */
 679     public void setDraggedColumn(TableColumn aColumn) {
 680         draggedColumn = aColumn;
 681     }
 682 
 683     /**
 684       *  Sets the header's <code>draggedDistance</code> to <code>distance</code>.
 685       *  @param distance  the distance dragged
 686       */
 687     public void setDraggedDistance(int distance) {
 688         draggedDistance = distance;
 689     }
 690 
 691     /**
 692       *  Sets the header's <code>resizingColumn</code> to <code>aColumn</code>.
 693       *  <p>
 694       *  Application code will not use this method explicitly, it
 695       *  is used internally by the column sizing mechanism.
 696       *
 697       *  @param  aColumn  the column being resized, or <code>null</code> if
 698       *                 no column is being resized
 699       */
 700     public void setResizingColumn(TableColumn aColumn) {
 701         resizingColumn = aColumn;
 702     }
 703 
 704     /**
 705      * See <code>readObject</code> and <code>writeObject</code> in
 706      * <code>JComponent</code> for more
 707      * information about serialization in Swing.
 708      */
 709     private void writeObject(ObjectOutputStream s) throws IOException {
 710         s.defaultWriteObject();
 711         if ((ui != null) && (getUIClassID().equals(uiClassID))) {
 712             ui.installUI(this);
 713         }
 714     }
 715 
 716     private int getWidthInRightToLeft() {
 717         if ((table != null) &&
 718             (table.getAutoResizeMode() != JTable.AUTO_RESIZE_OFF)) {
 719             return table.getWidth();
 720         }
 721         return super.getWidth();
 722     }
 723 
 724     /**
 725      * Returns a string representation of this <code>JTableHeader</code>. This method
 726      * is intended to be used only for debugging purposes, and the
 727      * content and format of the returned string may vary between
 728      * implementations. The returned string may be empty but may not
 729      * be <code>null</code>.
 730      * <P>
 731      * Overriding <code>paramString</code> to provide information about the
 732      * specific new aspects of the JFC components.
 733      *
 734      * @return  a string representation of this <code>JTableHeader</code>
 735      */
 736     protected String paramString() {
 737         String reorderingAllowedString = (reorderingAllowed ?
 738                                           "true" : "false");
 739         String resizingAllowedString = (resizingAllowed ?
 740                                         "true" : "false");
 741         String updateTableInRealTimeString = (updateTableInRealTime ?
 742                                               "true" : "false");
 743 
 744         return super.paramString() +
 745         ",draggedDistance=" + draggedDistance +
 746         ",reorderingAllowed=" + reorderingAllowedString +
 747         ",resizingAllowed=" + resizingAllowedString +
 748         ",updateTableInRealTime=" + updateTableInRealTimeString;
 749     }
 750 
 751 /////////////////
 752 // Accessibility support
 753 ////////////////
 754 
 755     /**
 756      * Gets the AccessibleContext associated with this JTableHeader.
 757      * For JTableHeaders, the AccessibleContext takes the form of an
 758      * AccessibleJTableHeader.
 759      * A new AccessibleJTableHeader instance is created if necessary.
 760      *
 761      * @return an AccessibleJTableHeader that serves as the
 762      *         AccessibleContext of this JTableHeader
 763      */
 764     public AccessibleContext getAccessibleContext() {
 765         if (accessibleContext == null) {
 766             accessibleContext = new AccessibleJTableHeader();
 767         }
 768         return accessibleContext;
 769     }
 770 
 771     //
 772     // *** should also implement AccessibleSelection?
 773     // *** and what's up with keyboard navigation/manipulation?
 774     //
 775     /**
 776      * This class implements accessibility support for the
 777      * <code>JTableHeader</code> class.  It provides an implementation of the
 778      * Java Accessibility API appropriate to table header user-interface
 779      * elements.
 780      * <p>
 781      * <strong>Warning:</strong>
 782      * Serialized objects of this class will not be compatible with
 783      * future Swing releases. The current serialization support is
 784      * appropriate for short term storage or RMI between applications running
 785      * the same version of Swing.  As of 1.4, support for long term storage
 786      * of all JavaBeans&trade;
 787      * has been added to the <code>java.beans</code> package.
 788      * Please see {@link java.beans.XMLEncoder}.
 789      */
 790     @SuppressWarnings("serial") // Same-version serialization only
 791     protected class AccessibleJTableHeader extends AccessibleJComponent {
 792 
 793         /**
 794          * Get the role of this object.
 795          *
 796          * @return an instance of AccessibleRole describing the role of the
 797          * object
 798          * @see AccessibleRole
 799          */
 800         public AccessibleRole getAccessibleRole() {
 801             return AccessibleRole.PANEL;
 802         }
 803 
 804         /**
 805          * Returns the Accessible child, if one exists, contained at the local
 806          * coordinate Point.
 807          *
 808          * @param p The point defining the top-left corner of the Accessible,
 809          * given in the coordinate space of the object's parent.
 810          * @return the Accessible, if it exists, at the specified location;
 811          * else null
 812          */
 813         public Accessible getAccessibleAt(Point p) {
 814             int column;
 815 
 816             // Locate the renderer under the Point
 817             if ((column = JTableHeader.this.columnAtPoint(p)) != -1) {
 818                 TableColumn aColumn = JTableHeader.this.columnModel.getColumn(column);
 819                 TableCellRenderer renderer = aColumn.getHeaderRenderer();
 820                 if (renderer == null) {
 821                     if (defaultRenderer != null) {
 822                         renderer = defaultRenderer;
 823                     } else {
 824                         return null;
 825                     }
 826                 }
 827                 Component component = renderer.getTableCellRendererComponent(
 828                                   JTableHeader.this.getTable(),
 829                                   aColumn.getHeaderValue(), false, false,
 830                                   -1, column);
 831 
 832                 return new AccessibleJTableHeaderEntry(column, JTableHeader.this, JTableHeader.this.table);
 833             } else {
 834                 return null;
 835             }
 836         }
 837 
 838         /**
 839          * Returns the number of accessible children in the object.  If all
 840          * of the children of this object implement Accessible, than this
 841          * method should return the number of children of this object.
 842          *
 843          * @return the number of accessible children in the object.
 844          */
 845         public int getAccessibleChildrenCount() {
 846             return JTableHeader.this.columnModel.getColumnCount();
 847         }
 848 
 849         /**
 850          * Return the nth Accessible child of the object.
 851          *
 852          * @param i zero-based index of child
 853          * @return the nth Accessible child of the object
 854          */
 855         public Accessible getAccessibleChild(int i) {
 856             if (i < 0 || i >= getAccessibleChildrenCount()) {
 857                 return null;
 858             } else {
 859                 TableColumn aColumn = JTableHeader.this.columnModel.getColumn(i)
 860 ;
 861                 TableCellRenderer renderer = aColumn.getHeaderRenderer();
 862                 if (renderer == null) {
 863                     if (defaultRenderer != null) {
 864                         renderer = defaultRenderer;
 865                     } else {
 866                         return null;
 867                     }
 868                 }
 869                 Component component = renderer.getTableCellRendererComponent(
 870                                   JTableHeader.this.getTable(),
 871                                   aColumn.getHeaderValue(), false, false,
 872                                   -1, i);
 873 
 874                 return new AccessibleJTableHeaderEntry(i, JTableHeader.this, JTableHeader.this.table);
 875             }
 876         }
 877 
 878       /**
 879        * This class provides an implementation of the Java Accessibility
 880        * API appropriate for JTableHeader entries.
 881        */
 882         protected class AccessibleJTableHeaderEntry extends AccessibleContext
 883             implements Accessible, AccessibleComponent  {
 884 
 885             private JTableHeader parent;
 886             private int column;
 887             private JTable table;
 888 
 889             /**
 890              *  Constructs an AccessiblJTableHeaaderEntry
 891              * @since 1.4
 892              *
 893              * @param c  the column index
 894              * @param p  the parent <code>JTableHeader</code>
 895              * @param t  the table <code>JTable</code>
 896              */
 897             public AccessibleJTableHeaderEntry(int c, JTableHeader p, JTable t) {
 898                 parent = p;
 899                 column = c;
 900                 table = t;
 901                 this.setAccessibleParent(parent);
 902             }
 903 
 904             /**
 905              * Get the AccessibleContext associated with this object.
 906              * In the implementation of the Java Accessibility API
 907              * for this class, returns this object, which serves as
 908              * its own AccessibleContext.
 909              *
 910              * @return this object
 911              */
 912             public AccessibleContext getAccessibleContext() {
 913                 return this;
 914             }
 915 
 916             private AccessibleContext getCurrentAccessibleContext() {
 917                 TableColumnModel tcm = table.getColumnModel();
 918                 if (tcm != null) {
 919                     // Fixes 4772355 - ArrayOutOfBoundsException in
 920                     // JTableHeader
 921                     if (column < 0 || column >= tcm.getColumnCount()) {
 922                         return null;
 923                     }
 924                     TableColumn aColumn = tcm.getColumn(column);
 925                     TableCellRenderer renderer = aColumn.getHeaderRenderer();
 926                     if (renderer == null) {
 927                         if (defaultRenderer != null) {
 928                             renderer = defaultRenderer;
 929                         } else {
 930                             return null;
 931                         }
 932                     }
 933                     Component c = renderer.getTableCellRendererComponent(
 934                                       JTableHeader.this.getTable(),
 935                                       aColumn.getHeaderValue(), false, false,
 936                                       -1, column);
 937                     if (c instanceof Accessible) {
 938                         return ((Accessible) c).getAccessibleContext();
 939                     }
 940                 }
 941                 return null;
 942             }
 943 
 944             private Component getCurrentComponent() {
 945                 TableColumnModel tcm = table.getColumnModel();
 946                 if (tcm != null) {
 947                     // Fixes 4772355 - ArrayOutOfBoundsException in
 948                     // JTableHeader
 949                     if (column < 0 || column >= tcm.getColumnCount()) {
 950                         return null;
 951                     }
 952                     TableColumn aColumn = tcm.getColumn(column);
 953                     TableCellRenderer renderer = aColumn.getHeaderRenderer();
 954                     if (renderer == null) {
 955                         if (defaultRenderer != null) {
 956                             renderer = defaultRenderer;
 957                         } else {
 958                             return null;
 959                         }
 960                     }
 961                     return renderer.getTableCellRendererComponent(
 962                                       JTableHeader.this.getTable(),
 963                                       aColumn.getHeaderValue(), false, false,
 964                                       -1, column);
 965                 } else {
 966                     return null;
 967                 }
 968             }
 969 
 970         // AccessibleContext methods
 971 
 972             public String getAccessibleName() {
 973                 AccessibleContext ac = getCurrentAccessibleContext();
 974                 if (ac != null) {
 975                     String name = ac.getAccessibleName();
 976                     if ((name != null) && (name != "")) {
 977                         // return the cell renderer's AccessibleName
 978                         return name;
 979                     }
 980                 }
 981                 if ((accessibleName != null) && (accessibleName != "")) {
 982                     return accessibleName;
 983                 } else {
 984                     // fall back to the client property
 985                     String name = (String)getClientProperty(AccessibleContext.ACCESSIBLE_NAME_PROPERTY);
 986                     if (name != null) {
 987                         return name;
 988                     } else {
 989                         return table.getColumnName(column);
 990                     }
 991                 }
 992             }
 993 
 994             public void setAccessibleName(String s) {
 995                 AccessibleContext ac = getCurrentAccessibleContext();
 996                 if (ac != null) {
 997                     ac.setAccessibleName(s);
 998                 } else {
 999                     super.setAccessibleName(s);
1000                 }
1001             }
1002 
1003             //
1004             // *** should check toolTip text for desc. (needs MouseEvent)
1005             //
1006             public String getAccessibleDescription() {
1007                 AccessibleContext ac = getCurrentAccessibleContext();
1008                 if (ac != null) {
1009                     return ac.getAccessibleDescription();
1010                 } else {
1011                     return super.getAccessibleDescription();
1012                 }
1013             }
1014 
1015             public void setAccessibleDescription(String s) {
1016                 AccessibleContext ac = getCurrentAccessibleContext();
1017                 if (ac != null) {
1018                     ac.setAccessibleDescription(s);
1019                 } else {
1020                     super.setAccessibleDescription(s);
1021                 }
1022             }
1023 
1024             public AccessibleRole getAccessibleRole() {
1025                 AccessibleContext ac = getCurrentAccessibleContext();
1026                 if (ac != null) {
1027                     return ac.getAccessibleRole();
1028                 } else {
1029                     return AccessibleRole.COLUMN_HEADER;
1030                 }
1031             }
1032 
1033             public AccessibleStateSet getAccessibleStateSet() {
1034                 AccessibleContext ac = getCurrentAccessibleContext();
1035                 if (ac != null) {
1036                     AccessibleStateSet states = ac.getAccessibleStateSet();
1037                     if (isShowing()) {
1038                         states.add(AccessibleState.SHOWING);
1039                     }
1040                     return states;
1041                 } else {
1042                     return new AccessibleStateSet();  // must be non null?
1043                 }
1044             }
1045 
1046             public int getAccessibleIndexInParent() {
1047                 return column;
1048             }
1049 
1050             public int getAccessibleChildrenCount() {
1051                 AccessibleContext ac = getCurrentAccessibleContext();
1052                 if (ac != null) {
1053                     return ac.getAccessibleChildrenCount();
1054                 } else {
1055                     return 0;
1056                 }
1057             }
1058 
1059             public Accessible getAccessibleChild(int i) {
1060                 AccessibleContext ac = getCurrentAccessibleContext();
1061                 if (ac != null) {
1062                     Accessible accessibleChild = ac.getAccessibleChild(i);
1063                     ac.setAccessibleParent(this);
1064                     return accessibleChild;
1065                 } else {
1066                     return null;
1067                 }
1068             }
1069 
1070             public Locale getLocale() {
1071                 AccessibleContext ac = getCurrentAccessibleContext();
1072                 if (ac != null) {
1073                     return ac.getLocale();
1074                 } else {
1075                     return null;
1076                 }
1077             }
1078 
1079             public void addPropertyChangeListener(PropertyChangeListener l) {
1080                 AccessibleContext ac = getCurrentAccessibleContext();
1081                 if (ac != null) {
1082                     ac.addPropertyChangeListener(l);
1083                 } else {
1084                     super.addPropertyChangeListener(l);
1085                 }
1086             }
1087 
1088             public void removePropertyChangeListener(PropertyChangeListener l) {
1089                 AccessibleContext ac = getCurrentAccessibleContext();
1090                 if (ac != null) {
1091                     ac.removePropertyChangeListener(l);
1092                 } else {
1093                     super.removePropertyChangeListener(l);
1094                 }
1095             }
1096 
1097             public AccessibleAction getAccessibleAction() {
1098                 return getCurrentAccessibleContext().getAccessibleAction();
1099             }
1100 
1101            /**
1102             * Get the AccessibleComponent associated with this object.  In the
1103             * implementation of the Java Accessibility API for this class,
1104             * return this object, which is responsible for implementing the
1105             * AccessibleComponent interface on behalf of itself.
1106             *
1107             * @return this object
1108             */
1109             public AccessibleComponent getAccessibleComponent() {
1110                 return this; // to override getBounds()
1111             }
1112 
1113             public AccessibleSelection getAccessibleSelection() {
1114                 return getCurrentAccessibleContext().getAccessibleSelection();
1115             }
1116 
1117             public AccessibleText getAccessibleText() {
1118                 return getCurrentAccessibleContext().getAccessibleText();
1119             }
1120 
1121             public AccessibleValue getAccessibleValue() {
1122                 return getCurrentAccessibleContext().getAccessibleValue();
1123             }
1124 
1125 
1126         // AccessibleComponent methods
1127 
1128             public Color getBackground() {
1129                 AccessibleContext ac = getCurrentAccessibleContext();
1130                 if (ac instanceof AccessibleComponent) {
1131                     return ((AccessibleComponent) ac).getBackground();
1132                 } else {
1133                     Component c = getCurrentComponent();
1134                     if (c != null) {
1135                         return c.getBackground();
1136                     } else {
1137                         return null;
1138                     }
1139                 }
1140             }
1141 
1142             public void setBackground(Color c) {
1143                 AccessibleContext ac = getCurrentAccessibleContext();
1144                 if (ac instanceof AccessibleComponent) {
1145                     ((AccessibleComponent) ac).setBackground(c);
1146                 } else {
1147                     Component cp = getCurrentComponent();
1148                     if (cp != null) {
1149                         cp.setBackground(c);
1150                     }
1151                 }
1152             }
1153 
1154             public Color getForeground() {
1155                 AccessibleContext ac = getCurrentAccessibleContext();
1156                 if (ac instanceof AccessibleComponent) {
1157                     return ((AccessibleComponent) ac).getForeground();
1158                 } else {
1159                     Component c = getCurrentComponent();
1160                     if (c != null) {
1161                         return c.getForeground();
1162                     } else {
1163                         return null;
1164                     }
1165                 }
1166             }
1167 
1168             public void setForeground(Color c) {
1169                 AccessibleContext ac = getCurrentAccessibleContext();
1170                 if (ac instanceof AccessibleComponent) {
1171                     ((AccessibleComponent) ac).setForeground(c);
1172                 } else {
1173                     Component cp = getCurrentComponent();
1174                     if (cp != null) {
1175                         cp.setForeground(c);
1176                     }
1177                 }
1178             }
1179 
1180             public Cursor getCursor() {
1181                 AccessibleContext ac = getCurrentAccessibleContext();
1182                 if (ac instanceof AccessibleComponent) {
1183                     return ((AccessibleComponent) ac).getCursor();
1184                 } else {
1185                     Component c = getCurrentComponent();
1186                     if (c != null) {
1187                         return c.getCursor();
1188                     } else {
1189                         Accessible ap = getAccessibleParent();
1190                         if (ap instanceof AccessibleComponent) {
1191                             return ((AccessibleComponent) ap).getCursor();
1192                         } else {
1193                             return null;
1194                         }
1195                     }
1196                 }
1197             }
1198 
1199             public void setCursor(Cursor c) {
1200                 AccessibleContext ac = getCurrentAccessibleContext();
1201                 if (ac instanceof AccessibleComponent) {
1202                     ((AccessibleComponent) ac).setCursor(c);
1203                 } else {
1204                     Component cp = getCurrentComponent();
1205                     if (cp != null) {
1206                         cp.setCursor(c);
1207                     }
1208                 }
1209             }
1210 
1211             public Font getFont() {
1212                 AccessibleContext ac = getCurrentAccessibleContext();
1213                 if (ac instanceof AccessibleComponent) {
1214                     return ((AccessibleComponent) ac).getFont();
1215                 } else {
1216                     Component c = getCurrentComponent();
1217                     if (c != null) {
1218                         return c.getFont();
1219                     } else {
1220                         return null;
1221                     }
1222                 }
1223             }
1224 
1225             public void setFont(Font f) {
1226                 AccessibleContext ac = getCurrentAccessibleContext();
1227                 if (ac instanceof AccessibleComponent) {
1228                     ((AccessibleComponent) ac).setFont(f);
1229                 } else {
1230                     Component c = getCurrentComponent();
1231                     if (c != null) {
1232                         c.setFont(f);
1233                     }
1234                 }
1235             }
1236 
1237             public FontMetrics getFontMetrics(Font f) {
1238                 AccessibleContext ac = getCurrentAccessibleContext();
1239                 if (ac instanceof AccessibleComponent) {
1240                     return ((AccessibleComponent) ac).getFontMetrics(f);
1241                 } else {
1242                     Component c = getCurrentComponent();
1243                     if (c != null) {
1244                         return c.getFontMetrics(f);
1245                     } else {
1246                         return null;
1247                     }
1248                 }
1249             }
1250 
1251             public boolean isEnabled() {
1252                 AccessibleContext ac = getCurrentAccessibleContext();
1253                 if (ac instanceof AccessibleComponent) {
1254                     return ((AccessibleComponent) ac).isEnabled();
1255                 } else {
1256                     Component c = getCurrentComponent();
1257                     if (c != null) {
1258                         return c.isEnabled();
1259                     } else {
1260                         return false;
1261                     }
1262                 }
1263             }
1264 
1265             public void setEnabled(boolean b) {
1266                 AccessibleContext ac = getCurrentAccessibleContext();
1267                 if (ac instanceof AccessibleComponent) {
1268                     ((AccessibleComponent) ac).setEnabled(b);
1269                 } else {
1270                     Component c = getCurrentComponent();
1271                     if (c != null) {
1272                         c.setEnabled(b);
1273                     }
1274                 }
1275             }
1276 
1277             public boolean isVisible() {
1278                 AccessibleContext ac = getCurrentAccessibleContext();
1279                 if (ac instanceof AccessibleComponent) {
1280                     return ((AccessibleComponent) ac).isVisible();
1281                 } else {
1282                     Component c = getCurrentComponent();
1283                     if (c != null) {
1284                         return c.isVisible();
1285                     } else {
1286                         return false;
1287                     }
1288                 }
1289             }
1290 
1291             public void setVisible(boolean b) {
1292                 AccessibleContext ac = getCurrentAccessibleContext();
1293                 if (ac instanceof AccessibleComponent) {
1294                     ((AccessibleComponent) ac).setVisible(b);
1295                 } else {
1296                     Component c = getCurrentComponent();
1297                     if (c != null) {
1298                         c.setVisible(b);
1299                     }
1300                 }
1301             }
1302 
1303             public boolean isShowing() {
1304                 if (isVisible() && JTableHeader.this.isShowing()) {
1305                     return true;
1306                 } else {
1307                     return false;
1308                 }
1309             }
1310 
1311             public boolean contains(Point p) {
1312                 AccessibleContext ac = getCurrentAccessibleContext();
1313                 if (ac instanceof AccessibleComponent) {
1314                     Rectangle r = ((AccessibleComponent) ac).getBounds();
1315                     return r.contains(p);
1316                 } else {
1317                     Component c = getCurrentComponent();
1318                     if (c != null) {
1319                         Rectangle r = c.getBounds();
1320                         return r.contains(p);
1321                     } else {
1322                         return getBounds().contains(p);
1323                     }
1324                 }
1325             }
1326 
1327             public Point getLocationOnScreen() {
1328                 if (parent != null) {
1329                     Point parentLocation = parent.getLocationOnScreen();
1330                     Point componentLocation = getLocation();
1331                     componentLocation.translate(parentLocation.x, parentLocation.y);
1332                     return componentLocation;
1333                 } else {
1334                     return null;
1335                 }
1336             }
1337 
1338             public Point getLocation() {
1339                 AccessibleContext ac = getCurrentAccessibleContext();
1340                 if (ac instanceof AccessibleComponent) {
1341                     Rectangle r = ((AccessibleComponent) ac).getBounds();
1342                     return r.getLocation();
1343                 } else {
1344                     Component c = getCurrentComponent();
1345                     if (c != null) {
1346                         Rectangle r = c.getBounds();
1347                         return r.getLocation();
1348                     } else {
1349                         return getBounds().getLocation();
1350                     }
1351                 }
1352             }
1353 
1354             public void setLocation(Point p) {
1355 //                if ((parent != null)  && (parent.contains(p))) {
1356 //                    ensureIndexIsVisible(indexInParent);
1357 //                }
1358             }
1359 
1360             public Rectangle getBounds() {
1361                   Rectangle r = table.getCellRect(-1, column, false);
1362                   r.y = 0;
1363                   return r;
1364 
1365 //                AccessibleContext ac = getCurrentAccessibleContext();
1366 //                if (ac instanceof AccessibleComponent) {
1367 //                    return ((AccessibleComponent) ac).getBounds();
1368 //                } else {
1369 //                  Component c = getCurrentComponent();
1370 //                  if (c != null) {
1371 //                      return c.getBounds();
1372 //                  } else {
1373 //                      Rectangle r = table.getCellRect(-1, column, false);
1374 //                      r.y = 0;
1375 //                      return r;
1376 //                  }
1377 //              }
1378             }
1379 
1380             public void setBounds(Rectangle r) {
1381                 AccessibleContext ac = getCurrentAccessibleContext();
1382                 if (ac instanceof AccessibleComponent) {
1383                     ((AccessibleComponent) ac).setBounds(r);
1384                 } else {
1385                     Component c = getCurrentComponent();
1386                     if (c != null) {
1387                         c.setBounds(r);
1388                     }
1389                 }
1390             }
1391 
1392             public Dimension getSize() {
1393                 return getBounds().getSize();
1394 //                AccessibleContext ac = getCurrentAccessibleContext();
1395 //                if (ac instanceof AccessibleComponent) {
1396 //                    Rectangle r = ((AccessibleComponent) ac).getBounds();
1397 //                    return r.getSize();
1398 //                } else {
1399 //                    Component c = getCurrentComponent();
1400 //                    if (c != null) {
1401 //                        Rectangle r = c.getBounds();
1402 //                        return r.getSize();
1403 //                    } else {
1404 //                        return getBounds().getSize();
1405 //                    }
1406 //                }
1407             }
1408 
1409             public void setSize (Dimension d) {
1410                 AccessibleContext ac = getCurrentAccessibleContext();
1411                 if (ac instanceof AccessibleComponent) {
1412                     ((AccessibleComponent) ac).setSize(d);
1413                 } else {
1414                     Component c = getCurrentComponent();
1415                     if (c != null) {
1416                         c.setSize(d);
1417                     }
1418                 }
1419             }
1420 
1421             public Accessible getAccessibleAt(Point p) {
1422                 AccessibleContext ac = getCurrentAccessibleContext();
1423                 if (ac instanceof AccessibleComponent) {
1424                     return ((AccessibleComponent) ac).getAccessibleAt(p);
1425                 } else {
1426                     return null;
1427                 }
1428             }
1429 
1430             public boolean isFocusTraversable() {
1431                 AccessibleContext ac = getCurrentAccessibleContext();
1432                 if (ac instanceof AccessibleComponent) {
1433                     return ((AccessibleComponent) ac).isFocusTraversable();
1434                 } else {
1435                     Component c = getCurrentComponent();
1436                     if (c != null) {
1437                         return c.isFocusTraversable();
1438                     } else {
1439                         return false;
1440                     }
1441                 }
1442             }
1443 
1444             public void requestFocus() {
1445                 AccessibleContext ac = getCurrentAccessibleContext();
1446                 if (ac instanceof AccessibleComponent) {
1447                     ((AccessibleComponent) ac).requestFocus();
1448                 } else {
1449                     Component c = getCurrentComponent();
1450                     if (c != null) {
1451                         c.requestFocus();
1452                     }
1453                 }
1454             }
1455 
1456             public void addFocusListener(FocusListener l) {
1457                 AccessibleContext ac = getCurrentAccessibleContext();
1458                 if (ac instanceof AccessibleComponent) {
1459                     ((AccessibleComponent) ac).addFocusListener(l);
1460                 } else {
1461                     Component c = getCurrentComponent();
1462                     if (c != null) {
1463                         c.addFocusListener(l);
1464                     }
1465                 }
1466             }
1467 
1468             public void removeFocusListener(FocusListener l) {
1469                 AccessibleContext ac = getCurrentAccessibleContext();
1470                 if (ac instanceof AccessibleComponent) {
1471                     ((AccessibleComponent) ac).removeFocusListener(l);
1472                 } else {
1473                     Component c = getCurrentComponent();
1474                     if (c != null) {
1475                         c.removeFocusListener(l);
1476                     }
1477                 }
1478             }
1479 
1480         } // inner class AccessibleJTableHeaderElement
1481 
1482     }  // inner class AccessibleJTableHeader
1483 
1484 }  // End of Class JTableHeader