summaryrefslogtreecommitdiffstats
path: root/server/src/com/vaadin/ui/TreeTable.java
blob: 058a8640ce352128c6220b4f08c6807b54f09db2 (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324
325
326
327
328
329
330
331
332
333
334
335
336
337
338
339
340
341
342
343
344
345
346
347
348
349
350
351
352
353
354
355
356
357
358
359
360
361
362
363
364
365
366
367
368
369
370
371
372
373
374
375
376
377
378
379
380
381
382
383
384
385
386
387
388
389
390
391
392
393
394
395
396
397
398
399
400
401
402
403
404
405
406
407
408
409
410
411
412
413
414
415
416
417
418
419
420
421
422
423
424
425
426
427
428
429
430
431
432
433
434
435
436
437
438
439
440
441
442
443
444
445
446
447
448
449
450
451
452
453
454
455
456
457
458
459
460
461
462
463
464
465
466
467
468
469
470
471
472
473
474
475
476
477
478
479
480
481
482
483
484
485
486
487
488
489
490
491
492
493
494
495
496
497
498
499
500
501
502
503
504
505
506
507
508
509
510
511
512
513
514
515
516
517
518
519
520
521
522
523
524
525
526
527
528
529
530
531
532
533
534
535
536
537
538
539
540
541
542
543
544
545
546
547
548
549
550
551
552
553
554
555
556
557
558
559
560
561
562
563
564
565
566
567
568
569
570
571
572
573
574
575
576
577
578
579
580
581
582
583
584
585
586
587
588
589
590
591
592
593
594
595
596
597
598
599
600
601
602
603
604
605
606
607
608
609
610
611
612
613
614
615
616
617
618
619
620
621
622
623
624
625
626
627
628
629
630
631
632
633
634
635
636
637
638
639
640
641
642
643
644
645
646
647
648
649
650
651
652
653
654
655
656
657
658
659
660
661
662
663
664
665
666
667
668
669
670
671
672
673
674
675
676
677
678
679
680
681
682
683
684
685
686
687
688
689
690
691
692
693
694
695
696
697
698
699
700
701
702
703
704
705
706
707
708
709
710
711
712
713
714
715
716
717
718
719
720
721
722
723
724
725
726
727
728
729
730
731
732
733
734
735
736
737
738
739
740
741
742
743
744
745
746
747
748
749
750
751
752
753
754
755
756
757
758
759
760
761
762
763
764
765
766
767
768
769
770
771
772
773
774
775
776
777
778
779
780
781
782
783
784
785
786
787
788
789
790
791
792
793
794
795
796
797
798
799
800
801
802
803
804
805
806
807
808
809
810
811
812
813
814
815
816
817
818
819
820
821
822
823
824
/*
@VaadinApache2LicenseForJavaFiles@
 */

package com.vaadin.ui;

import java.io.Serializable;
import java.util.ArrayList;
import java.util.Collection;
import java.util.Collections;
import java.util.HashSet;
import java.util.List;
import java.util.Map;
import java.util.logging.Logger;

import com.vaadin.data.Collapsible;
import com.vaadin.data.Container;
import com.vaadin.data.Container.Hierarchical;
import com.vaadin.data.Container.ItemSetChangeEvent;
import com.vaadin.data.util.ContainerHierarchicalWrapper;
import com.vaadin.data.util.HierarchicalContainer;
import com.vaadin.data.util.HierarchicalContainerOrderedWrapper;
import com.vaadin.shared.ui.treetable.TreeTableConstants;
import com.vaadin.terminal.PaintException;
import com.vaadin.terminal.PaintTarget;
import com.vaadin.terminal.Resource;
import com.vaadin.ui.Tree.CollapseEvent;
import com.vaadin.ui.Tree.CollapseListener;
import com.vaadin.ui.Tree.ExpandEvent;
import com.vaadin.ui.Tree.ExpandListener;

/**
 * TreeTable extends the {@link Table} component so that it can also visualize a
 * hierarchy of its Items in a similar manner that {@link Tree} does. The tree
 * hierarchy is always displayed in the first actual column of the TreeTable.
 * <p>
 * The TreeTable supports the usual {@link Table} features like lazy loading, so
 * it should be no problem to display lots of items at once. Only required rows
 * and some cache rows are sent to the client.
 * <p>
 * TreeTable supports standard {@link Hierarchical} container interfaces, but
 * also a more fine tuned version - {@link Collapsible}. A container
 * implementing the {@link Collapsible} interface stores the collapsed/expanded
 * state internally and can this way scale better on the server side than with
 * standard Hierarchical implementations. Developer must however note that
 * {@link Collapsible} containers can not be shared among several users as they
 * share UI state in the container.
 */
@SuppressWarnings({ "serial" })
public class TreeTable extends Table implements Hierarchical {

    private interface ContainerStrategy extends Serializable {
        public int size();

        public boolean isNodeOpen(Object itemId);

        public int getDepth(Object itemId);

        public void toggleChildVisibility(Object itemId);

        public Object getIdByIndex(int index);

        public int indexOfId(Object id);

        public Object nextItemId(Object itemId);

        public Object lastItemId();

        public Object prevItemId(Object itemId);

        public boolean isLastId(Object itemId);

        public Collection<?> getItemIds();

        public void containerItemSetChange(ItemSetChangeEvent event);
    }

    private abstract class AbstractStrategy implements ContainerStrategy {

        /**
         * Consider adding getDepth to {@link Collapsible}, might help
         * scalability with some container implementations.
         */

        @Override
        public int getDepth(Object itemId) {
            int depth = 0;
            Hierarchical hierarchicalContainer = getContainerDataSource();
            while (!hierarchicalContainer.isRoot(itemId)) {
                depth++;
                itemId = hierarchicalContainer.getParent(itemId);
            }
            return depth;
        }

        @Override
        public void containerItemSetChange(ItemSetChangeEvent event) {
        }

    }

    /**
     * This strategy is used if current container implements {@link Collapsible}
     * .
     * 
     * open-collapsed logic diverted to container, otherwise use default
     * implementations.
     */
    private class CollapsibleStrategy extends AbstractStrategy {

        private Collapsible c() {
            return (Collapsible) getContainerDataSource();
        }

        @Override
        public void toggleChildVisibility(Object itemId) {
            c().setCollapsed(itemId, !c().isCollapsed(itemId));
        }

        @Override
        public boolean isNodeOpen(Object itemId) {
            return !c().isCollapsed(itemId);
        }

        @Override
        public int size() {
            return TreeTable.super.size();
        }

        @Override
        public Object getIdByIndex(int index) {
            return TreeTable.super.getIdByIndex(index);
        }

        @Override
        public int indexOfId(Object id) {
            return TreeTable.super.indexOfId(id);
        }

        @Override
        public boolean isLastId(Object itemId) {
            // using the default impl
            return TreeTable.super.isLastId(itemId);
        }

        @Override
        public Object lastItemId() {
            // using the default impl
            return TreeTable.super.lastItemId();
        }

        @Override
        public Object nextItemId(Object itemId) {
            return TreeTable.super.nextItemId(itemId);
        }

        @Override
        public Object prevItemId(Object itemId) {
            return TreeTable.super.prevItemId(itemId);
        }

        @Override
        public Collection<?> getItemIds() {
            return TreeTable.super.getItemIds();
        }

    }

    /**
     * Strategy for Hierarchical but not Collapsible container like
     * {@link HierarchicalContainer}.
     * 
     * Store collapsed/open states internally, fool Table to use preorder when
     * accessing items from container via Ordered/Indexed methods.
     */
    private class HierarchicalStrategy extends AbstractStrategy {

        private final HashSet<Object> openItems = new HashSet<Object>();

        @Override
        public boolean isNodeOpen(Object itemId) {
            return openItems.contains(itemId);
        }

        @Override
        public int size() {
            return getPreOrder().size();
        }

        @Override
        public Collection<Object> getItemIds() {
            return Collections.unmodifiableCollection(getPreOrder());
        }

        @Override
        public boolean isLastId(Object itemId) {
            if (itemId == null) {
                return false;
            }

            return itemId.equals(lastItemId());
        }

        @Override
        public Object lastItemId() {
            if (getPreOrder().size() > 0) {
                return getPreOrder().get(getPreOrder().size() - 1);
            } else {
                return null;
            }
        }

        @Override
        public Object nextItemId(Object itemId) {
            int indexOf = getPreOrder().indexOf(itemId);
            if (indexOf == -1) {
                return null;
            }
            indexOf++;
            if (indexOf == getPreOrder().size()) {
                return null;
            } else {
                return getPreOrder().get(indexOf);
            }
        }

        @Override
        public Object prevItemId(Object itemId) {
            int indexOf = getPreOrder().indexOf(itemId);
            indexOf--;
            if (indexOf < 0) {
                return null;
            } else {
                return getPreOrder().get(indexOf);
            }
        }

        @Override
        public void toggleChildVisibility(Object itemId) {
            boolean removed = openItems.remove(itemId);
            if (!removed) {
                openItems.add(itemId);
                getLogger().finest("Item " + itemId + " is now expanded");
            } else {
                getLogger().finest("Item " + itemId + " is now collapsed");
            }
            clearPreorderCache();
        }

        private void clearPreorderCache() {
            preOrder = null; // clear preorder cache
        }

        List<Object> preOrder;

        /**
         * Preorder of ids currently visible
         * 
         * @return
         */
        private List<Object> getPreOrder() {
            if (preOrder == null) {
                preOrder = new ArrayList<Object>();
                Collection<?> rootItemIds = getContainerDataSource()
                        .rootItemIds();
                for (Object id : rootItemIds) {
                    preOrder.add(id);
                    addVisibleChildTree(id);
                }
            }
            return preOrder;
        }

        private void addVisibleChildTree(Object id) {
            if (isNodeOpen(id)) {
                Collection<?> children = getContainerDataSource().getChildren(
                        id);
                if (children != null) {
                    for (Object childId : children) {
                        preOrder.add(childId);
                        addVisibleChildTree(childId);
                    }
                }
            }

        }

        @Override
        public int indexOfId(Object id) {
            return getPreOrder().indexOf(id);
        }

        @Override
        public Object getIdByIndex(int index) {
            return getPreOrder().get(index);
        }

        @Override
        public void containerItemSetChange(ItemSetChangeEvent event) {
            // preorder becomes invalid on sort, item additions etc.
            clearPreorderCache();
            super.containerItemSetChange(event);
        }

    }

    /**
     * Creates an empty TreeTable with a default container.
     */
    public TreeTable() {
        super(null, new HierarchicalContainer());
    }

    /**
     * Creates an empty TreeTable with a default container.
     * 
     * @param caption
     *            the caption for the TreeTable
     */
    public TreeTable(String caption) {
        this();
        setCaption(caption);
    }

    /**
     * Creates a TreeTable instance with given captions and data source.
     * 
     * @param caption
     *            the caption for the component
     * @param dataSource
     *            the dataSource that is used to list items in the component
     */
    public TreeTable(String caption, Container dataSource) {
        super(caption, dataSource);
    }

    private ContainerStrategy cStrategy;
    private Object focusedRowId = null;
    private Object hierarchyColumnId;

    /**
     * The item id that was expanded or collapsed during this request. Reset at
     * the end of paint and only used for determining if a partial or full paint
     * should be done.
     * 
     * Can safely be reset to null whenever a change occurs that would prevent a
     * partial update from rendering the correct result, e.g. rows added or
     * removed during an expand operation.
     */
    private Object toggledItemId;
    private boolean animationsEnabled;
    private boolean clearFocusedRowPending;

    /**
     * If the container does not send item set change events, always do a full
     * repaint instead of a partial update when expanding/collapsing nodes.
     */
    private boolean containerSupportsPartialUpdates;

    private ContainerStrategy getContainerStrategy() {
        if (cStrategy == null) {
            if (getContainerDataSource() instanceof Collapsible) {
                cStrategy = new CollapsibleStrategy();
            } else {
                cStrategy = new HierarchicalStrategy();
            }
        }
        return cStrategy;
    }

    @Override
    protected void paintRowAttributes(PaintTarget target, Object itemId)
            throws PaintException {
        super.paintRowAttributes(target, itemId);
        target.addAttribute("depth", getContainerStrategy().getDepth(itemId));
        if (getContainerDataSource().areChildrenAllowed(itemId)) {
            target.addAttribute("ca", true);
            target.addAttribute("open",
                    getContainerStrategy().isNodeOpen(itemId));
        }
    }

    @Override
    protected void paintRowIcon(PaintTarget target, Object[][] cells,
            int indexInRowbuffer) throws PaintException {
        // always paint if present (in parent only if row headers visible)
        if (getRowHeaderMode() == ROW_HEADER_MODE_HIDDEN) {
            Resource itemIcon = getItemIcon(cells[CELL_ITEMID][indexInRowbuffer]);
            if (itemIcon != null) {
                target.addAttribute("icon", itemIcon);
            }
        } else if (cells[CELL_ICON][indexInRowbuffer] != null) {
            target.addAttribute("icon",
                    (Resource) cells[CELL_ICON][indexInRowbuffer]);
        }
    }

    @Override
    public void changeVariables(Object source, Map<String, Object> variables) {
        super.changeVariables(source, variables);

        if (variables.containsKey("toggleCollapsed")) {
            String object = (String) variables.get("toggleCollapsed");
            Object itemId = itemIdMapper.get(object);
            toggledItemId = itemId;
            toggleChildVisibility(itemId, false);
            if (variables.containsKey("selectCollapsed")) {
                // ensure collapsed is selected unless opened with selection
                // head
                if (isSelectable()) {
                    select(itemId);
                }
            }
        } else if (variables.containsKey("focusParent")) {
            String key = (String) variables.get("focusParent");
            Object refId = itemIdMapper.get(key);
            Object itemId = getParent(refId);
            focusParent(itemId);
        }
    }

    private void focusParent(Object itemId) {
        boolean inView = false;
        Object inPageId = getCurrentPageFirstItemId();
        for (int i = 0; inPageId != null && i < getPageLength(); i++) {
            if (inPageId.equals(itemId)) {
                inView = true;
                break;
            }
            inPageId = nextItemId(inPageId);
            i++;
        }
        if (!inView) {
            setCurrentPageFirstItemId(itemId);
        }
        // Select the row if it is selectable.
        if (isSelectable()) {
            if (isMultiSelect()) {
                setValue(Collections.singleton(itemId));
            } else {
                setValue(itemId);
            }
        }
        setFocusedRow(itemId);
    }

    private void setFocusedRow(Object itemId) {
        focusedRowId = itemId;
        if (focusedRowId == null) {
            // Must still inform the client that the focusParent request has
            // been processed
            clearFocusedRowPending = true;
        }
        requestRepaint();
    }

    @Override
    public void paintContent(PaintTarget target) throws PaintException {
        if (focusedRowId != null) {
            target.addAttribute("focusedRow", itemIdMapper.key(focusedRowId));
            focusedRowId = null;
        } else if (clearFocusedRowPending) {
            // Must still inform the client that the focusParent request has
            // been processed
            target.addAttribute("clearFocusPending", true);
            clearFocusedRowPending = false;
        }
        target.addAttribute("animate", animationsEnabled);
        if (hierarchyColumnId != null) {
            Object[] visibleColumns2 = getVisibleColumns();
            for (int i = 0; i < visibleColumns2.length; i++) {
                Object object = visibleColumns2[i];
                if (hierarchyColumnId.equals(object)) {
                    target.addAttribute(
                            TreeTableConstants.ATTRIBUTE_HIERARCHY_COLUMN_INDEX,
                            i);
                    break;
                }
            }
        }
        super.paintContent(target);
        toggledItemId = null;
    }

    /*
     * Override methods for partial row updates and additions when expanding /
     * collapsing nodes.
     */

    @Override
    protected boolean isPartialRowUpdate() {
        return toggledItemId != null && containerSupportsPartialUpdates
                && !isRowCacheInvalidated();
    }

    @Override
    protected int getFirstAddedItemIndex() {
        return indexOfId(toggledItemId) + 1;
    }

    @Override
    protected int getAddedRowCount() {
        return countSubNodesRecursively(getContainerDataSource(), toggledItemId);
    }

    private int countSubNodesRecursively(Hierarchical hc, Object itemId) {
        int count = 0;
        // we need the number of children for toggledItemId no matter if its
        // collapsed or expanded. Other items' children are only counted if the
        // item is expanded.
        if (getContainerStrategy().isNodeOpen(itemId)
                || itemId == toggledItemId) {
            Collection<?> children = hc.getChildren(itemId);
            if (children != null) {
                count += children != null ? children.size() : 0;
                for (Object id : children) {
                    count += countSubNodesRecursively(hc, id);
                }
            }
        }
        return count;
    }

    @Override
    protected int getFirstUpdatedItemIndex() {
        return indexOfId(toggledItemId);
    }

    @Override
    protected int getUpdatedRowCount() {
        return 1;
    }

    @Override
    protected boolean shouldHideAddedRows() {
        return !getContainerStrategy().isNodeOpen(toggledItemId);
    }

    private void toggleChildVisibility(Object itemId, boolean forceFullRefresh) {
        getContainerStrategy().toggleChildVisibility(itemId);
        // ensure that page still has first item in page, DON'T clear the
        // caches.
        setCurrentPageFirstItemIndex(getCurrentPageFirstItemIndex(), false);

        if (isCollapsed(itemId)) {
            fireCollapseEvent(itemId);
        } else {
            fireExpandEvent(itemId);
        }

        if (containerSupportsPartialUpdates && !forceFullRefresh) {
            requestRepaint();
        } else {
            // For containers that do not send item set change events, always do
            // full repaint instead of partial row update.
            refreshRowCache();
        }
    }

    @Override
    public int size() {
        return getContainerStrategy().size();
    }

    @Override
    public Hierarchical getContainerDataSource() {
        return (Hierarchical) super.getContainerDataSource();
    }

    @Override
    public void setContainerDataSource(Container newDataSource) {
        cStrategy = null;

        // FIXME: This disables partial updates until TreeTable is fixed so it
        // does not change component hierarchy during paint
        containerSupportsPartialUpdates = (newDataSource instanceof ItemSetChangeNotifier) && false;

        if (!(newDataSource instanceof Hierarchical)) {
            newDataSource = new ContainerHierarchicalWrapper(newDataSource);
        }

        if (!(newDataSource instanceof Ordered)) {
            newDataSource = new HierarchicalContainerOrderedWrapper(
                    (Hierarchical) newDataSource);
        }

        super.setContainerDataSource(newDataSource);
    }

    @Override
    public void containerItemSetChange(
            com.vaadin.data.Container.ItemSetChangeEvent event) {
        // Can't do partial repaints if items are added or removed during the
        // expand/collapse request
        toggledItemId = null;
        getContainerStrategy().containerItemSetChange(event);
        super.containerItemSetChange(event);
    }

    @Override
    protected Object getIdByIndex(int index) {
        return getContainerStrategy().getIdByIndex(index);
    }

    @Override
    protected int indexOfId(Object itemId) {
        return getContainerStrategy().indexOfId(itemId);
    }

    @Override
    public Object nextItemId(Object itemId) {
        return getContainerStrategy().nextItemId(itemId);
    }

    @Override
    public Object lastItemId() {
        return getContainerStrategy().lastItemId();
    }

    @Override
    public Object prevItemId(Object itemId) {
        return getContainerStrategy().prevItemId(itemId);
    }

    @Override
    public boolean isLastId(Object itemId) {
        return getContainerStrategy().isLastId(itemId);
    }

    @Override
    public Collection<?> getItemIds() {
        return getContainerStrategy().getItemIds();
    }

    @Override
    public boolean areChildrenAllowed(Object itemId) {
        return getContainerDataSource().areChildrenAllowed(itemId);
    }

    @Override
    public Collection<?> getChildren(Object itemId) {
        return getContainerDataSource().getChildren(itemId);
    }

    @Override
    public Object getParent(Object itemId) {
        return getContainerDataSource().getParent(itemId);
    }

    @Override
    public boolean hasChildren(Object itemId) {
        return getContainerDataSource().hasChildren(itemId);
    }

    @Override
    public boolean isRoot(Object itemId) {
        return getContainerDataSource().isRoot(itemId);
    }

    @Override
    public Collection<?> rootItemIds() {
        return getContainerDataSource().rootItemIds();
    }

    @Override
    public boolean setChildrenAllowed(Object itemId, boolean areChildrenAllowed)
            throws UnsupportedOperationException {
        return getContainerDataSource().setChildrenAllowed(itemId,
                areChildrenAllowed);
    }

    @Override
    public boolean setParent(Object itemId, Object newParentId)
            throws UnsupportedOperationException {
        return getContainerDataSource().setParent(itemId, newParentId);
    }

    /**
     * Sets the Item specified by given identifier as collapsed or expanded. If
     * the Item is collapsed, its children are not displayed to the user.
     * 
     * @param itemId
     *            the identifier of the Item
     * @param collapsed
     *            true if the Item should be collapsed, false if expanded
     */
    public void setCollapsed(Object itemId, boolean collapsed) {
        if (isCollapsed(itemId) != collapsed) {
            if (null == toggledItemId && !isRowCacheInvalidated()
                    && getVisibleItemIds().contains(itemId)) {
                // optimization: partial refresh if only one item is
                // collapsed/expanded
                toggledItemId = itemId;
                toggleChildVisibility(itemId, false);
            } else {
                // make sure a full refresh takes place - otherwise neither
                // partial nor full repaint of table content is performed
                toggledItemId = null;
                toggleChildVisibility(itemId, true);
            }
        }
    }

    /**
     * Checks if Item with given identifier is collapsed in the UI.
     * 
     * <p>
     * 
     * @param itemId
     *            the identifier of the checked Item
     * @return true if the Item with given id is collapsed
     * @see Collapsible#isCollapsed(Object)
     */
    public boolean isCollapsed(Object itemId) {
        return !getContainerStrategy().isNodeOpen(itemId);
    }

    /**
     * Explicitly sets the column in which the TreeTable visualizes the
     * hierarchy. If hierarchyColumnId is not set, the hierarchy is visualized
     * in the first visible column.
     * 
     * @param hierarchyColumnId
     */
    public void setHierarchyColumn(Object hierarchyColumnId) {
        this.hierarchyColumnId = hierarchyColumnId;
    }

    /**
     * @return the identifier of column into which the hierarchy will be
     *         visualized or null if the column is not explicitly defined.
     */
    public Object getHierarchyColumnId() {
        return hierarchyColumnId;
    }

    /**
     * Adds an expand listener.
     * 
     * @param listener
     *            the Listener to be added.
     */
    public void addListener(ExpandListener listener) {
        addListener(ExpandEvent.class, listener, ExpandListener.EXPAND_METHOD);
    }

    /**
     * Removes an expand listener.
     * 
     * @param listener
     *            the Listener to be removed.
     */
    public void removeListener(ExpandListener listener) {
        removeListener(ExpandEvent.class, listener,
                ExpandListener.EXPAND_METHOD);
    }

    /**
     * Emits an expand event.
     * 
     * @param itemId
     *            the item id.
     */
    protected void fireExpandEvent(Object itemId) {
        fireEvent(new ExpandEvent(this, itemId));
    }

    /**
     * Adds a collapse listener.
     * 
     * @param listener
     *            the Listener to be added.
     */
    public void addListener(CollapseListener listener) {
        addListener(CollapseEvent.class, listener,
                CollapseListener.COLLAPSE_METHOD);
    }

    /**
     * Removes a collapse listener.
     * 
     * @param listener
     *            the Listener to be removed.
     */
    public void removeListener(CollapseListener listener) {
        removeListener(CollapseEvent.class, listener,
                CollapseListener.COLLAPSE_METHOD);
    }

    /**
     * Emits a collapse event.
     * 
     * @param itemId
     *            the item id.
     */
    protected void fireCollapseEvent(Object itemId) {
        fireEvent(new CollapseEvent(this, itemId));
    }

    /**
     * @return true if animations are enabled
     */
    public boolean isAnimationsEnabled() {
        return animationsEnabled;
    }

    /**
     * Animations can be enabled by passing true to this method. Currently
     * expanding rows slide in from the top and collapsing rows slide out the
     * same way. NOTE! not supported in Internet Explorer 6 or 7.
     * 
     * @param animationsEnabled
     *            true or false whether to enable animations or not.
     */
    public void setAnimationsEnabled(boolean animationsEnabled) {
        this.animationsEnabled = animationsEnabled;
        requestRepaint();
    }

    private static final Logger getLogger() {
        return Logger.getLogger(TreeTable.class.getName());
    }

}