summaryrefslogtreecommitdiff
path: root/android/view/accessibility/AccessibilityRecord.java
blob: 0a709f8f52d509d2f78cd9681677db73ae282df8 (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
825
826
827
828
829
830
831
832
833
834
835
836
837
838
839
840
841
842
843
844
845
846
847
848
849
850
851
852
853
854
855
856
857
858
859
860
861
862
863
864
865
866
867
868
869
870
871
872
873
874
875
876
877
878
879
880
881
882
883
884
885
886
887
888
889
890
891
892
893
894
895
896
897
898
899
900
901
902
903
904
905
906
907
908
909
910
911
912
913
914
915
916
917
918
919
920
921
922
923
924
925
926
927
928
929
930
931
932
933
934
935
936
937
938
939
940
941
942
943
944
945
946
947
948
949
950
951
952
953
954
955
956
957
958
959
960
/*
 * Copyright (C) 2011 The Android Open Source Project
 *
 * Licensed under the Apache License, Version 2.0 (the "License");
 * you may not use this file except in compliance with the License.
 * You may obtain a copy of the License at
 *
 *      http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 */

package android.view.accessibility;

import static com.android.internal.util.CollectionUtils.isEmpty;

import android.annotation.Nullable;
import android.os.Parcelable;
import android.view.View;

import java.util.ArrayList;
import java.util.List;

/**
 * Represents a record in an {@link AccessibilityEvent} and contains information
 * about state change of its source {@link android.view.View}. When a view fires
 * an accessibility event it requests from its parent to dispatch the
 * constructed event. The parent may optionally append a record for itself
 * for providing more context to
 * {@link android.accessibilityservice.AccessibilityService}s. Hence,
 * accessibility services can facilitate additional accessibility records
 * to enhance feedback.
 * </p>
 * <p>
 * Once the accessibility event containing a record is dispatched the record is
 * made immutable and calling a state mutation method generates an error.
 * </p>
 * <p>
 * <strong>Note:</strong> Not all properties are applicable to all accessibility
 * event types. For detailed information please refer to {@link AccessibilityEvent}.
 * </p>
 *
 * <div class="special reference">
 * <h3>Developer Guides</h3>
 * <p>For more information about creating and processing AccessibilityRecords, read the
 * <a href="{@docRoot}guide/topics/ui/accessibility/index.html">Accessibility</a>
 * developer guide.</p>
 * </div>
 *
 * @see AccessibilityEvent
 * @see AccessibilityManager
 * @see android.accessibilityservice.AccessibilityService
 * @see AccessibilityNodeInfo
 */
public class AccessibilityRecord {
    /** @hide */
    protected static final boolean DEBUG_CONCISE_TOSTRING = false;

    private static final int UNDEFINED = -1;

    private static final int PROPERTY_CHECKED = 0x00000001;
    private static final int PROPERTY_ENABLED = 0x00000002;
    private static final int PROPERTY_PASSWORD = 0x00000004;
    private static final int PROPERTY_FULL_SCREEN = 0x00000080;
    private static final int PROPERTY_SCROLLABLE = 0x00000100;
    private static final int PROPERTY_IMPORTANT_FOR_ACCESSIBILITY = 0x00000200;

    private static final int GET_SOURCE_PREFETCH_FLAGS =
        AccessibilityNodeInfo.FLAG_PREFETCH_PREDECESSORS
        | AccessibilityNodeInfo.FLAG_PREFETCH_SIBLINGS
        | AccessibilityNodeInfo.FLAG_PREFETCH_DESCENDANTS;

    // Housekeeping
    private static final int MAX_POOL_SIZE = 10;
    private static final Object sPoolLock = new Object();
    private static AccessibilityRecord sPool;
    private static int sPoolSize;
    private AccessibilityRecord mNext;
    private boolean mIsInPool;

    boolean mSealed;
    int mBooleanProperties = 0;
    int mCurrentItemIndex = UNDEFINED;
    int mItemCount = UNDEFINED;
    int mFromIndex = UNDEFINED;
    int mToIndex = UNDEFINED;
    int mScrollX = UNDEFINED;
    int mScrollY = UNDEFINED;

    int mScrollDeltaX = UNDEFINED;
    int mScrollDeltaY = UNDEFINED;
    int mMaxScrollX = UNDEFINED;
    int mMaxScrollY = UNDEFINED;

    int mAddedCount= UNDEFINED;
    int mRemovedCount = UNDEFINED;
    long mSourceNodeId = AccessibilityNodeInfo.UNDEFINED_NODE_ID;
    int mSourceWindowId = AccessibilityWindowInfo.UNDEFINED_WINDOW_ID;

    CharSequence mClassName;
    CharSequence mContentDescription;
    CharSequence mBeforeText;
    Parcelable mParcelableData;

    final List<CharSequence> mText = new ArrayList<CharSequence>();

    int mConnectionId = UNDEFINED;

    /*
     * Hide constructor.
     */
    AccessibilityRecord() {
    }

    /**
     * Sets the event source.
     *
     * @param source The source.
     *
     * @throws IllegalStateException If called from an AccessibilityService.
     */
    public void setSource(View source) {
        setSource(source, AccessibilityNodeProvider.HOST_VIEW_ID);
    }

    /**
     * Sets the source to be a virtual descendant of the given <code>root</code>.
     * If <code>virtualDescendantId</code> equals to {@link View#NO_ID} the root
     * is set as the source.
     * <p>
     * A virtual descendant is an imaginary View that is reported as a part of the view
     * hierarchy for accessibility purposes. This enables custom views that draw complex
     * content to report them selves as a tree of virtual views, thus conveying their
     * logical structure.
     * </p>
     *
     * @param root The root of the virtual subtree.
     * @param virtualDescendantId The id of the virtual descendant.
     */
    public void setSource(@Nullable View root, int virtualDescendantId) {
        enforceNotSealed();
        boolean important = true;
        int rootViewId = AccessibilityNodeInfo.UNDEFINED_ITEM_ID;
        mSourceWindowId = AccessibilityWindowInfo.UNDEFINED_WINDOW_ID;
        if (root != null) {
            important = root.isImportantForAccessibility();
            rootViewId = root.getAccessibilityViewId();
            mSourceWindowId = root.getAccessibilityWindowId();
        }
        setBooleanProperty(PROPERTY_IMPORTANT_FOR_ACCESSIBILITY, important);
        mSourceNodeId = AccessibilityNodeInfo.makeNodeId(rootViewId, virtualDescendantId);
    }

    /**
     * Set the source node ID directly
     *
     * @param sourceNodeId The source node Id
     * @hide
     */
    public void setSourceNodeId(long sourceNodeId) {
        mSourceNodeId = sourceNodeId;
    }

    /**
     * Gets the {@link AccessibilityNodeInfo} of the event source.
     * <p>
     *   <strong>Note:</strong> It is a client responsibility to recycle the received info
     *   by calling {@link AccessibilityNodeInfo#recycle() AccessibilityNodeInfo#recycle()}
     *   to avoid creating of multiple instances.
     * </p>
     * @return The info of the source.
     */
    public AccessibilityNodeInfo getSource() {
        enforceSealed();
        if ((mConnectionId == UNDEFINED)
                || (mSourceWindowId == AccessibilityWindowInfo.UNDEFINED_WINDOW_ID)
                || (AccessibilityNodeInfo.getAccessibilityViewId(mSourceNodeId)
                        == AccessibilityNodeInfo.UNDEFINED_ITEM_ID)) {
            return null;
        }
        AccessibilityInteractionClient client = AccessibilityInteractionClient.getInstance();
        return client.findAccessibilityNodeInfoByAccessibilityId(mConnectionId, mSourceWindowId,
                mSourceNodeId, false, GET_SOURCE_PREFETCH_FLAGS, null);
    }

    /**
     * Sets the window id.
     *
     * @param windowId The window id.
     *
     * @hide
     */
    public void setWindowId(int windowId) {
        mSourceWindowId = windowId;
    }

    /**
     * Gets the id of the window from which the event comes from.
     *
     * @return The window id.
     */
    public int getWindowId() {
        return mSourceWindowId;
    }

    /**
     * Gets if the source is checked.
     *
     * @return True if the view is checked, false otherwise.
     */
    public boolean isChecked() {
        return getBooleanProperty(PROPERTY_CHECKED);
    }

    /**
     * Sets if the source is checked.
     *
     * @param isChecked True if the view is checked, false otherwise.
     *
     * @throws IllegalStateException If called from an AccessibilityService.
     */
    public void setChecked(boolean isChecked) {
        enforceNotSealed();
        setBooleanProperty(PROPERTY_CHECKED, isChecked);
    }

    /**
     * Gets if the source is enabled.
     *
     * @return True if the view is enabled, false otherwise.
     */
    public boolean isEnabled() {
        return getBooleanProperty(PROPERTY_ENABLED);
    }

    /**
     * Sets if the source is enabled.
     *
     * @param isEnabled True if the view is enabled, false otherwise.
     *
     * @throws IllegalStateException If called from an AccessibilityService.
     */
    public void setEnabled(boolean isEnabled) {
        enforceNotSealed();
        setBooleanProperty(PROPERTY_ENABLED, isEnabled);
    }

    /**
     * Gets if the source is a password field.
     *
     * @return True if the view is a password field, false otherwise.
     */
    public boolean isPassword() {
        return getBooleanProperty(PROPERTY_PASSWORD);
    }

    /**
     * Sets if the source is a password field.
     *
     * @param isPassword True if the view is a password field, false otherwise.
     *
     * @throws IllegalStateException If called from an AccessibilityService.
     */
    public void setPassword(boolean isPassword) {
        enforceNotSealed();
        setBooleanProperty(PROPERTY_PASSWORD, isPassword);
    }

    /**
     * Gets if the source is taking the entire screen.
     *
     * @return True if the source is full screen, false otherwise.
     */
    public boolean isFullScreen() {
        return getBooleanProperty(PROPERTY_FULL_SCREEN);
    }

    /**
     * Sets if the source is taking the entire screen.
     *
     * @param isFullScreen True if the source is full screen, false otherwise.
     *
     * @throws IllegalStateException If called from an AccessibilityService.
     */
    public void setFullScreen(boolean isFullScreen) {
        enforceNotSealed();
        setBooleanProperty(PROPERTY_FULL_SCREEN, isFullScreen);
    }

    /**
     * Gets if the source is scrollable.
     *
     * @return True if the source is scrollable, false otherwise.
     */
    public boolean isScrollable() {
        return getBooleanProperty(PROPERTY_SCROLLABLE);
    }

    /**
     * Sets if the source is scrollable.
     *
     * @param scrollable True if the source is scrollable, false otherwise.
     *
     * @throws IllegalStateException If called from an AccessibilityService.
     */
    public void setScrollable(boolean scrollable) {
        enforceNotSealed();
        setBooleanProperty(PROPERTY_SCROLLABLE, scrollable);
    }

    /**
     * Gets if the source is important for accessibility.
     *
     * <strong>Note:</strong> Used only internally to determine whether
     * to deliver the event to a given accessibility service since some
     * services may want to regard all views for accessibility while others
     * may want to regard only the important views for accessibility.
     *
     * @return True if the source is important for accessibility,
     *        false otherwise.
     *
     * @hide
     */
    public boolean isImportantForAccessibility() {
        return getBooleanProperty(PROPERTY_IMPORTANT_FOR_ACCESSIBILITY);
    }

    /**
     * Sets if the source is important for accessibility.
     *
     * @param importantForAccessibility True if the source is important for accessibility,
     *                                  false otherwise.
     *
     * @throws IllegalStateException If called from an AccessibilityService.
     * @hide
     */
    public void setImportantForAccessibility(boolean importantForAccessibility) {
        enforceNotSealed();
        setBooleanProperty(PROPERTY_IMPORTANT_FOR_ACCESSIBILITY, importantForAccessibility);
    }

    /**
     * Gets the number of items that can be visited.
     *
     * @return The number of items.
     */
    public int getItemCount() {
        return mItemCount;
    }

    /**
     * Sets the number of items that can be visited.
     *
     * @param itemCount The number of items.
     *
     * @throws IllegalStateException If called from an AccessibilityService.
     */
    public void setItemCount(int itemCount) {
        enforceNotSealed();
        mItemCount = itemCount;
    }

    /**
     * Gets the index of the source in the list of items the can be visited.
     *
     * @return The current item index.
     */
    public int getCurrentItemIndex() {
        return mCurrentItemIndex;
    }

    /**
     * Sets the index of the source in the list of items that can be visited.
     *
     * @param currentItemIndex The current item index.
     *
     * @throws IllegalStateException If called from an AccessibilityService.
     */
    public void setCurrentItemIndex(int currentItemIndex) {
        enforceNotSealed();
        mCurrentItemIndex = currentItemIndex;
    }

    /**
     * Gets the index of the first character of the changed sequence,
     * or the beginning of a text selection or the index of the first
     * visible item when scrolling.
     *
     * @return The index of the first character or selection
     *        start or the first visible item.
     */
    public int getFromIndex() {
        return mFromIndex;
    }

    /**
     * Sets the index of the first character of the changed sequence
     * or the beginning of a text selection or the index of the first
     * visible item when scrolling.
     *
     * @param fromIndex The index of the first character or selection
     *        start or the first visible item.
     *
     * @throws IllegalStateException If called from an AccessibilityService.
     */
    public void setFromIndex(int fromIndex) {
        enforceNotSealed();
        mFromIndex = fromIndex;
    }

    /**
     * Gets the index of text selection end or the index of the last
     * visible item when scrolling.
     *
     * @return The index of selection end or last item index.
     */
    public int getToIndex() {
        return mToIndex;
    }

    /**
     * Sets the index of text selection end or the index of the last
     * visible item when scrolling.
     *
     * @param toIndex The index of selection end or last item index.
     */
    public void setToIndex(int toIndex) {
        enforceNotSealed();
        mToIndex = toIndex;
    }

    /**
     * Gets the scroll offset of the source left edge in pixels.
     *
     * @return The scroll.
     */
    public int getScrollX() {
        return mScrollX;
    }

    /**
     * Sets the scroll offset of the source left edge in pixels.
     *
     * @param scrollX The scroll.
     */
    public void setScrollX(int scrollX) {
        enforceNotSealed();
        mScrollX = scrollX;
    }

    /**
     * Gets the scroll offset of the source top edge in pixels.
     *
     * @return The scroll.
     */
    public int getScrollY() {
        return mScrollY;
    }

    /**
     * Sets the scroll offset of the source top edge in pixels.
     *
     * @param scrollY The scroll.
     */
    public void setScrollY(int scrollY) {
        enforceNotSealed();
        mScrollY = scrollY;
    }

    /**
     * Gets the difference in pixels between the horizontal position before the scroll and the
     * current horizontal position
     *
     * @return the scroll delta x
     */
    public int getScrollDeltaX() {
        return mScrollDeltaX;
    }

    /**
     * Sets the difference in pixels between the horizontal position before the scroll and the
     * current horizontal position
     *
     * @param scrollDeltaX the scroll delta x
     */
    public void setScrollDeltaX(int scrollDeltaX) {
        enforceNotSealed();
        mScrollDeltaX = scrollDeltaX;
    }

    /**
     * Gets the difference in pixels between the vertical position before the scroll and the
     * current vertical position
     *
     * @return the scroll delta y
     */
    public int getScrollDeltaY() {
        return mScrollDeltaY;
    }

    /**
     * Sets the difference in pixels between the vertical position before the scroll and the
     * current vertical position
     *
     * @param scrollDeltaY the scroll delta y
     */
    public void setScrollDeltaY(int scrollDeltaY) {
        enforceNotSealed();
        mScrollDeltaY = scrollDeltaY;
    }

    /**
     * Gets the max scroll offset of the source left edge in pixels.
     *
     * @return The max scroll.
     */
    public int getMaxScrollX() {
        return mMaxScrollX;
    }

    /**
     * Sets the max scroll offset of the source left edge in pixels.
     *
     * @param maxScrollX The max scroll.
     */
    public void setMaxScrollX(int maxScrollX) {
        enforceNotSealed();
        mMaxScrollX = maxScrollX;
    }

    /**
     * Gets the max scroll offset of the source top edge in pixels.
     *
     * @return The max scroll.
     */
    public int getMaxScrollY() {
        return mMaxScrollY;
    }

    /**
     * Sets the max scroll offset of the source top edge in pixels.
     *
     * @param maxScrollY The max scroll.
     */
    public void setMaxScrollY(int maxScrollY) {
        enforceNotSealed();
        mMaxScrollY = maxScrollY;
    }

    /**
     * Gets the number of added characters.
     *
     * @return The number of added characters.
     */
    public int getAddedCount() {
        return mAddedCount;
    }

    /**
     * Sets the number of added characters.
     *
     * @param addedCount The number of added characters.
     *
     * @throws IllegalStateException If called from an AccessibilityService.
     */
    public void setAddedCount(int addedCount) {
        enforceNotSealed();
        mAddedCount = addedCount;
    }

    /**
     * Gets the number of removed characters.
     *
     * @return The number of removed characters.
     */
    public int getRemovedCount() {
        return mRemovedCount;
    }

    /**
     * Sets the number of removed characters.
     *
     * @param removedCount The number of removed characters.
     *
     * @throws IllegalStateException If called from an AccessibilityService.
     */
    public void setRemovedCount(int removedCount) {
        enforceNotSealed();
        mRemovedCount = removedCount;
    }

    /**
     * Gets the class name of the source.
     *
     * @return The class name.
     */
    public CharSequence getClassName() {
        return mClassName;
    }

    /**
     * Sets the class name of the source.
     *
     * @param className The lass name.
     *
     * @throws IllegalStateException If called from an AccessibilityService.
     */
    public void setClassName(CharSequence className) {
        enforceNotSealed();
        mClassName = className;
    }

    /**
     * Gets the text of the event. The index in the list represents the priority
     * of the text. Specifically, the lower the index the higher the priority.
     *
     * @return The text.
     */
    public List<CharSequence> getText() {
        return mText;
    }

    /**
     * Sets the text before a change.
     *
     * @return The text before the change.
     */
    public CharSequence getBeforeText() {
        return mBeforeText;
    }

    /**
     * Sets the text before a change.
     *
     * @param beforeText The text before the change.
     *
     * @throws IllegalStateException If called from an AccessibilityService.
     */
    public void setBeforeText(CharSequence beforeText) {
        enforceNotSealed();
        mBeforeText = (beforeText == null) ? null
                : beforeText.subSequence(0, beforeText.length());
    }

    /**
     * Gets the description of the source.
     *
     * @return The description.
     */
    public CharSequence getContentDescription() {
        return mContentDescription;
    }

    /**
     * Sets the description of the source.
     *
     * @param contentDescription The description.
     *
     * @throws IllegalStateException If called from an AccessibilityService.
     */
    public void setContentDescription(CharSequence contentDescription) {
        enforceNotSealed();
        mContentDescription = (contentDescription == null) ? null
                : contentDescription.subSequence(0, contentDescription.length());
    }

    /**
     * Gets the {@link Parcelable} data.
     *
     * @return The parcelable data.
     */
    public Parcelable getParcelableData() {
        return mParcelableData;
    }

    /**
     * Sets the {@link Parcelable} data of the event.
     *
     * @param parcelableData The parcelable data.
     *
     * @throws IllegalStateException If called from an AccessibilityService.
     */
    public void setParcelableData(Parcelable parcelableData) {
        enforceNotSealed();
        mParcelableData = parcelableData;
    }

    /**
     * Gets the id of the source node.
     *
     * @return The id.
     *
     * @hide
     */
    public long getSourceNodeId() {
        return mSourceNodeId;
    }

    /**
     * Sets the unique id of the IAccessibilityServiceConnection over which
     * this instance can send requests to the system.
     *
     * @param connectionId The connection id.
     *
     * @hide
     */
    public void setConnectionId(int connectionId) {
        enforceNotSealed();
        mConnectionId = connectionId;
    }

    /**
     * Sets if this instance is sealed.
     *
     * @param sealed Whether is sealed.
     *
     * @hide
     */
    public void setSealed(boolean sealed) {
        mSealed = sealed;
    }

    /**
     * Gets if this instance is sealed.
     *
     * @return Whether is sealed.
     */
    boolean isSealed() {
        return mSealed;
    }

    /**
     * Enforces that this instance is sealed.
     *
     * @throws IllegalStateException If this instance is not sealed.
     */
    void enforceSealed() {
        if (!isSealed()) {
            throw new IllegalStateException("Cannot perform this "
                    + "action on a not sealed instance.");
        }
    }

    /**
     * Enforces that this instance is not sealed.
     *
     * @throws IllegalStateException If this instance is sealed.
     */
    void enforceNotSealed() {
        if (isSealed()) {
            throw new IllegalStateException("Cannot perform this "
                    + "action on a sealed instance.");
        }
    }

    /**
     * Gets the value of a boolean property.
     *
     * @param property The property.
     * @return The value.
     */
    private boolean getBooleanProperty(int property) {
        return (mBooleanProperties & property) == property;
    }

    /**
     * Sets a boolean property.
     *
     * @param property The property.
     * @param value The value.
     */
    private void setBooleanProperty(int property, boolean value) {
        if (value) {
            mBooleanProperties |= property;
        } else {
            mBooleanProperties &= ~property;
        }
    }

    /**
     * Returns a cached instance if such is available or a new one is
     * instantiated. The instance is initialized with data from the
     * given record.
     *
     * @return An instance.
     */
    public static AccessibilityRecord obtain(AccessibilityRecord record) {
       AccessibilityRecord clone = AccessibilityRecord.obtain();
       clone.init(record);
       return clone;
    }

    /**
     * Returns a cached instance if such is available or a new one is
     * instantiated.
     *
     * @return An instance.
     */
    public static AccessibilityRecord obtain() {
        synchronized (sPoolLock) {
            if (sPool != null) {
                AccessibilityRecord record = sPool;
                sPool = sPool.mNext;
                sPoolSize--;
                record.mNext = null;
                record.mIsInPool = false;
                return record;
            }
            return new AccessibilityRecord();
        }
    }

    /**
     * Return an instance back to be reused.
     * <p>
     * <strong>Note:</strong> You must not touch the object after calling this function.
     *
     * @throws IllegalStateException If the record is already recycled.
     */
    public void recycle() {
        if (mIsInPool) {
            throw new IllegalStateException("Record already recycled!");
        }
        clear();
        synchronized (sPoolLock) {
            if (sPoolSize <= MAX_POOL_SIZE) {
                mNext = sPool;
                sPool = this;
                mIsInPool = true;
                sPoolSize++;
            }
        }
    }

    /**
     * Initialize this record from another one.
     *
     * @param record The to initialize from.
     */
    void init(AccessibilityRecord record) {
        mSealed = record.mSealed;
        mBooleanProperties = record.mBooleanProperties;
        mCurrentItemIndex = record.mCurrentItemIndex;
        mItemCount = record.mItemCount;
        mFromIndex = record.mFromIndex;
        mToIndex = record.mToIndex;
        mScrollX = record.mScrollX;
        mScrollY = record.mScrollY;
        mMaxScrollX = record.mMaxScrollX;
        mMaxScrollY = record.mMaxScrollY;
        mAddedCount = record.mAddedCount;
        mRemovedCount = record.mRemovedCount;
        mClassName = record.mClassName;
        mContentDescription = record.mContentDescription;
        mBeforeText = record.mBeforeText;
        mParcelableData = record.mParcelableData;
        mText.addAll(record.mText);
        mSourceWindowId = record.mSourceWindowId;
        mSourceNodeId = record.mSourceNodeId;
        mConnectionId = record.mConnectionId;
    }

    /**
     * Clears the state of this instance.
     */
    void clear() {
        mSealed = false;
        mBooleanProperties = 0;
        mCurrentItemIndex = UNDEFINED;
        mItemCount = UNDEFINED;
        mFromIndex = UNDEFINED;
        mToIndex = UNDEFINED;
        mScrollX = UNDEFINED;
        mScrollY = UNDEFINED;
        mMaxScrollX = UNDEFINED;
        mMaxScrollY = UNDEFINED;
        mAddedCount = UNDEFINED;
        mRemovedCount = UNDEFINED;
        mClassName = null;
        mContentDescription = null;
        mBeforeText = null;
        mParcelableData = null;
        mText.clear();
        mSourceNodeId = AccessibilityNodeInfo.UNDEFINED_ITEM_ID;
        mSourceWindowId = AccessibilityWindowInfo.UNDEFINED_WINDOW_ID;
        mConnectionId = UNDEFINED;
    }

    @Override
    public String toString() {
        return appendTo(new StringBuilder()).toString();
    }

    StringBuilder appendTo(StringBuilder builder) {
        builder.append(" [ ClassName: ").append(mClassName);
        if (!DEBUG_CONCISE_TOSTRING || !isEmpty(mText)) {
            appendPropName(builder, "Text").append(mText);
        }
        append(builder, "ContentDescription", mContentDescription);
        append(builder, "ItemCount", mItemCount);
        append(builder, "CurrentItemIndex", mCurrentItemIndex);

        appendUnless(true, PROPERTY_ENABLED, builder);
        appendUnless(false, PROPERTY_PASSWORD, builder);
        appendUnless(false, PROPERTY_CHECKED, builder);
        appendUnless(false, PROPERTY_FULL_SCREEN, builder);
        appendUnless(false, PROPERTY_SCROLLABLE, builder);

        append(builder, "BeforeText", mBeforeText);
        append(builder, "FromIndex", mFromIndex);
        append(builder, "ToIndex", mToIndex);
        append(builder, "ScrollX", mScrollX);
        append(builder, "ScrollY", mScrollY);
        append(builder, "MaxScrollX", mMaxScrollX);
        append(builder, "MaxScrollY", mMaxScrollY);
        append(builder, "AddedCount", mAddedCount);
        append(builder, "RemovedCount", mRemovedCount);
        append(builder, "ParcelableData", mParcelableData);
        builder.append(" ]");
        return builder;
    }

    private void appendUnless(boolean defValue, int prop, StringBuilder builder) {
        boolean value = getBooleanProperty(prop);
        if (DEBUG_CONCISE_TOSTRING && value == defValue) return;
        appendPropName(builder, singleBooleanPropertyToString(prop))
                .append(value);
    }

    private static String singleBooleanPropertyToString(int prop) {
        switch (prop) {
            case PROPERTY_CHECKED: return "Checked";
            case PROPERTY_ENABLED: return "Enabled";
            case PROPERTY_PASSWORD: return "Password";
            case PROPERTY_FULL_SCREEN: return "FullScreen";
            case PROPERTY_SCROLLABLE: return "Scrollable";
            case PROPERTY_IMPORTANT_FOR_ACCESSIBILITY:
                return "ImportantForAccessibility";
            default: return Integer.toHexString(prop);
        }
    }

    private void append(StringBuilder builder, String propName, int propValue) {
        if (DEBUG_CONCISE_TOSTRING && propValue == UNDEFINED) return;
        appendPropName(builder, propName).append(propValue);
    }

    private void append(StringBuilder builder, String propName, Object propValue) {
        if (DEBUG_CONCISE_TOSTRING && propValue == null) return;
        appendPropName(builder, propName).append(propValue);
    }

    private StringBuilder appendPropName(StringBuilder builder, String propName) {
        return builder.append("; ").append(propName).append(": ");
    }
}