forked from bjmashibing/java
-
Notifications
You must be signed in to change notification settings - Fork 0
Expand file tree
/
Copy pathDeque.html
More file actions
1334 lines (1308 loc) · 65.7 KB
/
Copy pathDeque.html
File metadata and controls
1334 lines (1308 loc) · 65.7 KB
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
961
962
963
964
965
966
967
968
969
970
971
972
973
974
975
976
977
978
979
980
981
982
983
984
985
986
987
988
989
990
991
992
993
994
995
996
997
998
999
1000
<!DOCTYPE HTML>
<!-- NewPage -->
<html lang="en">
<head>
<!-- Generated by javadoc -->
<title>Deque (Java SE 12 & JDK 12 )</title>
<meta http-equiv="Content-Type" content="text/html; charset=UTF-8">
<meta name="keywords" content="java.util.Deque interface">
<meta name="keywords" content="addFirst()">
<meta name="keywords" content="addLast()">
<meta name="keywords" content="offerFirst()">
<meta name="keywords" content="offerLast()">
<meta name="keywords" content="removeFirst()">
<meta name="keywords" content="removeLast()">
<meta name="keywords" content="pollFirst()">
<meta name="keywords" content="pollLast()">
<meta name="keywords" content="getFirst()">
<meta name="keywords" content="getLast()">
<meta name="keywords" content="peekFirst()">
<meta name="keywords" content="peekLast()">
<meta name="keywords" content="removeFirstOccurrence()">
<meta name="keywords" content="removeLastOccurrence()">
<meta name="keywords" content="add()">
<meta name="keywords" content="offer()">
<meta name="keywords" content="remove()">
<meta name="keywords" content="poll()">
<meta name="keywords" content="element()">
<meta name="keywords" content="peek()">
<meta name="keywords" content="addAll()">
<meta name="keywords" content="push()">
<meta name="keywords" content="pop()">
<meta name="keywords" content="contains()">
<meta name="keywords" content="size()">
<meta name="keywords" content="iterator()">
<meta name="keywords" content="descendingIterator()">
<link rel="stylesheet" type="text/css" href="../../../stylesheet.css" title="Style">
<link rel="stylesheet" type="text/css" href="../../../jquery/jquery-ui.css" title="Style">
<script type="text/javascript" src="../../../script.js"></script>
<script type="text/javascript" src="../../../jquery/jszip/dist/jszip.min.js"></script>
<script type="text/javascript" src="../../../jquery/jszip-utils/dist/jszip-utils.min.js"></script>
<!--[if IE]>
<script type="text/javascript" src="../../../jquery/jszip-utils/dist/jszip-utils-ie.min.js"></script>
<![endif]-->
<script type="text/javascript" src="../../../jquery/jquery-3.3.1.js"></script>
<script type="text/javascript" src="../../../jquery/jquery-migrate-3.0.1.js"></script>
<script type="text/javascript" src="../../../jquery/jquery-ui.js"></script>
</head>
<body>
<script type="text/javascript"><!--
try {
if (location.href.indexOf('is-external=true') == -1) {
parent.document.title="Deque (Java SE 12 & JDK 12 )";
}
}
catch(err) {
}
//-->
var data = {"i0":6,"i1":6,"i2":6,"i3":6,"i4":6,"i5":6,"i6":6,"i7":6,"i8":6,"i9":6,"i10":6,"i11":6,"i12":6,"i13":6,"i14":6,"i15":6,"i16":6,"i17":6,"i18":6,"i19":6,"i20":6,"i21":6,"i22":6,"i23":6,"i24":6,"i25":6,"i26":6,"i27":6};
var tabs = {65535:["t0","All Methods"],2:["t2","Instance Methods"],4:["t3","Abstract Methods"]};
var altColor = "altColor";
var rowColor = "rowColor";
var tableTab = "tableTab";
var activeTableTab = "activeTableTab";
var pathtoroot = "../../../";
var useModuleDirectories = true;
loadScripts(document, 'script');</script>
<noscript>
<div>JavaScript is disabled on your browser.</div>
</noscript>
<header role="banner">
<nav role="navigation">
<div class="fixedNav">
<!-- ========= START OF TOP NAVBAR ======= -->
<div class="topNav"><a id="navbar.top">
<!-- -->
</a>
<div class="skipNav"><a href="#skip.navbar.top" title="Skip navigation links">Skip navigation links</a></div>
<a id="navbar.top.firstrow">
<!-- -->
</a>
<ul class="navList" title="Navigation">
<li><a href="../../../index.html">Overview</a></li>
<li><a href="../../module-summary.html">Module</a></li>
<li><a href="package-summary.html">Package</a></li>
<li class="navBarCell1Rev">Class</li>
<li><a href="class-use/Deque.html">Use</a></li>
<li><a href="package-tree.html">Tree</a></li>
<li><a href="../../../deprecated-list.html">Deprecated</a></li>
<li><a href="../../../index-files/index-1.html">Index</a></li>
<li><a href="../../../help-doc.html">Help</a></li>
</ul>
<div class="aboutLanguage"><div style="margin-top: 14px;"><strong>Java SE 12 & JDK 12</strong> </div></div>
</div>
<div class="subNav">
<div>
<ul class="subNavList">
<li>Summary: </li>
<li>Nested | </li>
<li>Field | </li>
<li>Constr | </li>
<li><a href="#method.summary">Method</a></li>
</ul>
<ul class="subNavList">
<li>Detail: </li>
<li>Field | </li>
<li>Constr | </li>
<li><a href="#method.detail">Method</a></li>
</ul>
</div>
<ul class="navListSearch">
<li><label for="search">SEARCH:</label>
<input type="text" id="search" value="search" disabled="disabled">
<input type="reset" id="reset" value="reset" disabled="disabled">
</li>
</ul>
</div>
<a id="skip.navbar.top">
<!-- -->
</a>
<!-- ========= END OF TOP NAVBAR ========= -->
</div>
<div class="navPadding"> </div>
<script type="text/javascript"><!--
$('.navPadding').css('padding-top', $('.fixedNav').css("height"));
//-->
</script>
</nav>
</header>
<!-- ======== START OF CLASS DATA ======== -->
<main role="main">
<div class="header">
<div class="subTitle"><span class="moduleLabelInType">Module</span> <a href="../../module-summary.html">java.base</a></div>
<div class="subTitle"><span class="packageLabelInType">Package</span> <a href="package-summary.html">java.util</a></div>
<h2 title="Interface Deque" class="title">Interface Deque<E></h2>
</div>
<div class="contentContainer">
<div class="description">
<ul class="blockList">
<li class="blockList">
<dl>
<dt><span class="paramLabel">Type Parameters:</span></dt>
<dd><code>E</code> - the type of elements held in this deque</dd>
</dl>
<dl>
<dt>All Superinterfaces:</dt>
<dd><code><a href="Collection.html" title="interface in java.util">Collection</a><E></code>, <code><a href="../lang/Iterable.html" title="interface in java.lang">Iterable</a><E></code>, <code><a href="Queue.html" title="interface in java.util">Queue</a><E></code></dd>
</dl>
<dl>
<dt>All Known Subinterfaces:</dt>
<dd><code><a href="concurrent/BlockingDeque.html" title="interface in java.util.concurrent">BlockingDeque</a><E></code></dd>
</dl>
<dl>
<dt>All Known Implementing Classes:</dt>
<dd><code><a href="ArrayDeque.html" title="class in java.util">ArrayDeque</a></code>, <code><a href="concurrent/ConcurrentLinkedDeque.html" title="class in java.util.concurrent">ConcurrentLinkedDeque</a></code>, <code><a href="concurrent/LinkedBlockingDeque.html" title="class in java.util.concurrent">LinkedBlockingDeque</a></code>, <code><a href="LinkedList.html" title="class in java.util">LinkedList</a></code></dd>
</dl>
<hr>
<pre>public interface <span class="typeNameLabel">Deque<E></span>
extends <a href="Queue.html" title="interface in java.util">Queue</a><E></pre>
<div class="block">A linear collection that supports element insertion and removal at
both ends. The name <i>deque</i> is short for "double ended queue"
and is usually pronounced "deck". Most <code>Deque</code>
implementations place no fixed limits on the number of elements
they may contain, but this interface supports capacity-restricted
deques as well as those with no fixed size limit.
<p>This interface defines methods to access the elements at both
ends of the deque. Methods are provided to insert, remove, and
examine the element. Each of these methods exists in two forms:
one throws an exception if the operation fails, the other returns a
special value (either <code>null</code> or <code>false</code>, depending on
the operation). The latter form of the insert operation is
designed specifically for use with capacity-restricted
<code>Deque</code> implementations; in most implementations, insert
operations cannot fail.
<p>The twelve methods described above are summarized in the
following table:
<table class="striped">
<caption>Summary of Deque methods</caption>
<thead>
<tr>
<td rowspan="2"></td>
<th scope="col" colspan="2"> First Element (Head)</th>
<th scope="col" colspan="2"> Last Element (Tail)</th>
</tr>
<tr>
<th scope="col" style="font-weight:normal; font-style:italic">Throws exception</th>
<th scope="col" style="font-weight:normal; font-style:italic">Special value</th>
<th scope="col" style="font-weight:normal; font-style:italic">Throws exception</th>
<th scope="col" style="font-weight:normal; font-style:italic">Special value</th>
</tr>
</thead>
<tbody>
<tr>
<th scope="row">Insert</th>
<td><a href="#addFirst(E)"><code>addFirst(e)</code></a></td>
<td><a href="#offerFirst(E)"><code>offerFirst(e)</code></a></td>
<td><a href="#addLast(E)"><code>addLast(e)</code></a></td>
<td><a href="#offerLast(E)"><code>offerLast(e)</code></a></td>
</tr>
<tr>
<th scope="row">Remove</th>
<td><a href="#removeFirst()"><code>removeFirst()</code></a></td>
<td><a href="#pollFirst()"><code>pollFirst()</code></a></td>
<td><a href="#removeLast()"><code>removeLast()</code></a></td>
<td><a href="#pollLast()"><code>pollLast()</code></a></td>
</tr>
<tr>
<th scope="row">Examine</th>
<td><a href="#getFirst()"><code>getFirst()</code></a></td>
<td><a href="#peekFirst()"><code>peekFirst()</code></a></td>
<td><a href="#getLast()"><code>getLast()</code></a></td>
<td><a href="#peekLast()"><code>peekLast()</code></a></td>
</tr>
</tbody>
</table>
<p>This interface extends the <a href="Queue.html" title="interface in java.util"><code>Queue</code></a> interface. When a deque is
used as a queue, FIFO (First-In-First-Out) behavior results. Elements are
added at the end of the deque and removed from the beginning. The methods
inherited from the <code>Queue</code> interface are precisely equivalent to
<code>Deque</code> methods as indicated in the following table:
<table class="striped">
<caption>Comparison of Queue and Deque methods</caption>
<thead>
<tr>
<th scope="col"> <code>Queue</code> Method</th>
<th scope="col"> Equivalent <code>Deque</code> Method</th>
</tr>
</thead>
<tbody>
<tr>
<th scope="row"><a href="#add(E)"><code>add(e)</code></a></th>
<td><a href="#addLast(E)"><code>addLast(e)</code></a></td>
</tr>
<tr>
<th scope="row"><a href="#offer(E)"><code>offer(e)</code></a></th>
<td><a href="#offerLast(E)"><code>offerLast(e)</code></a></td>
</tr>
<tr>
<th scope="row"><a href="#remove()"><code>remove()</code></a></th>
<td><a href="#removeFirst()"><code>removeFirst()</code></a></td>
</tr>
<tr>
<th scope="row"><a href="#poll()"><code>poll()</code></a></th>
<td><a href="#pollFirst()"><code>pollFirst()</code></a></td>
</tr>
<tr>
<th scope="row"><a href="#element()"><code>element()</code></a></th>
<td><a href="#getFirst()"><code>getFirst()</code></a></td>
</tr>
<tr>
<th scope="row"><a href="#peek()"><code>peek()</code></a></th>
<td><a href="#peekFirst()"><code>peekFirst()</code></a></td>
</tr>
</tbody>
</table>
<p>Deques can also be used as LIFO (Last-In-First-Out) stacks. This
interface should be used in preference to the legacy <a href="Stack.html" title="class in java.util"><code>Stack</code></a> class.
When a deque is used as a stack, elements are pushed and popped from the
beginning of the deque. Stack methods are equivalent to <code>Deque</code>
methods as indicated in the table below:
<table class="striped">
<caption>Comparison of Stack and Deque methods</caption>
<thead>
<tr>
<th scope="col"> Stack Method</th>
<th scope="col"> Equivalent <code>Deque</code> Method</th>
</tr>
</thead>
<tbody>
<tr>
<th scope="row"><a href="#push(E)"><code>push(e)</code></a></th>
<td><a href="#addFirst(E)"><code>addFirst(e)</code></a></td>
</tr>
<tr>
<th scope="row"><a href="#pop()"><code>pop()</code></a></th>
<td><a href="#removeFirst()"><code>removeFirst()</code></a></td>
</tr>
<tr>
<th scope="row"><a href="#peek()"><code>peek()</code></a></th>
<td><a href="#getFirst()"><code>getFirst()</code></a></td>
</tr>
</tbody>
</table>
<p>Note that the <a href="#peek()"><code>peek</code></a> method works equally well when
a deque is used as a queue or a stack; in either case, elements are
drawn from the beginning of the deque.
<p>This interface provides two methods to remove interior
elements, <a href="#removeFirstOccurrence(java.lang.Object)"><code>removeFirstOccurrence</code></a> and
<a href="#removeLastOccurrence(java.lang.Object)"><code>removeLastOccurrence</code></a>.
<p>Unlike the <a href="List.html" title="interface in java.util"><code>List</code></a> interface, this interface does not
provide support for indexed access to elements.
<p>While <code>Deque</code> implementations are not strictly required
to prohibit the insertion of null elements, they are strongly
encouraged to do so. Users of any <code>Deque</code> implementations
that do allow null elements are strongly encouraged <i>not</i> to
take advantage of the ability to insert nulls. This is so because
<code>null</code> is used as a special return value by various methods
to indicate that the deque is empty.
<p><code>Deque</code> implementations generally do not define
element-based versions of the <code>equals</code> and <code>hashCode</code>
methods, but instead inherit the identity-based versions from class
<code>Object</code>.
<p>This interface is a member of the
<a href="../../../java.base/java/util/package-summary.html#CollectionsFramework">
Java Collections Framework</a>.</div>
<dl>
<dt><span class="simpleTagLabel">Since:</span></dt>
<dd>1.6</dd>
</dl>
</li>
</ul>
</div>
<div class="summary">
<ul class="blockList">
<li class="blockList">
<!-- ========== METHOD SUMMARY =========== -->
<section role="region">
<ul class="blockList">
<li class="blockList"><a id="method.summary">
<!-- -->
</a>
<h3>Method Summary</h3>
<div class="memberSummary">
<div role="tablist" aria-orientation="horizontal"><button role="tab" aria-selected="true" aria-controls="memberSummary_tabpanel" tabindex="0" onkeydown="switchTab(event)" id="t0" class="activeTableTab">All Methods</button><button role="tab" aria-selected="false" aria-controls="memberSummary_tabpanel" tabindex="-1" onkeydown="switchTab(event)" id="t2" class="tableTab" onclick="show(2);">Instance Methods</button><button role="tab" aria-selected="false" aria-controls="memberSummary_tabpanel" tabindex="-1" onkeydown="switchTab(event)" id="t3" class="tableTab" onclick="show(4);">Abstract Methods</button></div>
<div id="memberSummary_tabpanel" role="tabpanel">
<table aria-labelledby="t0">
<tr>
<th class="colFirst" scope="col">Modifier and Type</th>
<th class="colSecond" scope="col">Method</th>
<th class="colLast" scope="col">Description</th>
</tr>
<tbody>
<tr class="altColor" id="i0">
<td class="colFirst"><code>boolean</code></td>
<th class="colSecond" scope="row"><code><span class="memberNameLink"><a href="#add(E)">add</a></span>​(<a href="Deque.html" title="type parameter in Deque">E</a> e)</code></th>
<td class="colLast">
<div class="block">Inserts the specified element into the queue represented by this deque
(in other words, at the tail of this deque) if it is possible to do so
immediately without violating capacity restrictions, returning
<code>true</code> upon success and throwing an
<code>IllegalStateException</code> if no space is currently available.</div>
</td>
</tr>
<tr class="rowColor" id="i1">
<td class="colFirst"><code>boolean</code></td>
<th class="colSecond" scope="row"><code><span class="memberNameLink"><a href="#addAll(java.util.Collection)">addAll</a></span>​(<a href="Collection.html" title="interface in java.util">Collection</a><? extends <a href="Deque.html" title="type parameter in Deque">E</a>> c)</code></th>
<td class="colLast">
<div class="block">Adds all of the elements in the specified collection at the end
of this deque, as if by calling <a href="#addLast(E)"><code>addLast(E)</code></a> on each one,
in the order that they are returned by the collection's iterator.</div>
</td>
</tr>
<tr class="altColor" id="i2">
<td class="colFirst"><code>void</code></td>
<th class="colSecond" scope="row"><code><span class="memberNameLink"><a href="#addFirst(E)">addFirst</a></span>​(<a href="Deque.html" title="type parameter in Deque">E</a> e)</code></th>
<td class="colLast">
<div class="block">Inserts the specified element at the front of this deque if it is
possible to do so immediately without violating capacity restrictions,
throwing an <code>IllegalStateException</code> if no space is currently
available.</div>
</td>
</tr>
<tr class="rowColor" id="i3">
<td class="colFirst"><code>void</code></td>
<th class="colSecond" scope="row"><code><span class="memberNameLink"><a href="#addLast(E)">addLast</a></span>​(<a href="Deque.html" title="type parameter in Deque">E</a> e)</code></th>
<td class="colLast">
<div class="block">Inserts the specified element at the end of this deque if it is
possible to do so immediately without violating capacity restrictions,
throwing an <code>IllegalStateException</code> if no space is currently
available.</div>
</td>
</tr>
<tr class="altColor" id="i4">
<td class="colFirst"><code>boolean</code></td>
<th class="colSecond" scope="row"><code><span class="memberNameLink"><a href="#contains(java.lang.Object)">contains</a></span>​(<a href="../lang/Object.html" title="class in java.lang">Object</a> o)</code></th>
<td class="colLast">
<div class="block">Returns <code>true</code> if this deque contains the specified element.</div>
</td>
</tr>
<tr class="rowColor" id="i5">
<td class="colFirst"><code><a href="Iterator.html" title="interface in java.util">Iterator</a><<a href="Deque.html" title="type parameter in Deque">E</a>></code></td>
<th class="colSecond" scope="row"><code><span class="memberNameLink"><a href="#descendingIterator()">descendingIterator</a></span>()</code></th>
<td class="colLast">
<div class="block">Returns an iterator over the elements in this deque in reverse
sequential order.</div>
</td>
</tr>
<tr class="altColor" id="i6">
<td class="colFirst"><code><a href="Deque.html" title="type parameter in Deque">E</a></code></td>
<th class="colSecond" scope="row"><code><span class="memberNameLink"><a href="#element()">element</a></span>()</code></th>
<td class="colLast">
<div class="block">Retrieves, but does not remove, the head of the queue represented by
this deque (in other words, the first element of this deque).</div>
</td>
</tr>
<tr class="rowColor" id="i7">
<td class="colFirst"><code><a href="Deque.html" title="type parameter in Deque">E</a></code></td>
<th class="colSecond" scope="row"><code><span class="memberNameLink"><a href="#getFirst()">getFirst</a></span>()</code></th>
<td class="colLast">
<div class="block">Retrieves, but does not remove, the first element of this deque.</div>
</td>
</tr>
<tr class="altColor" id="i8">
<td class="colFirst"><code><a href="Deque.html" title="type parameter in Deque">E</a></code></td>
<th class="colSecond" scope="row"><code><span class="memberNameLink"><a href="#getLast()">getLast</a></span>()</code></th>
<td class="colLast">
<div class="block">Retrieves, but does not remove, the last element of this deque.</div>
</td>
</tr>
<tr class="rowColor" id="i9">
<td class="colFirst"><code><a href="Iterator.html" title="interface in java.util">Iterator</a><<a href="Deque.html" title="type parameter in Deque">E</a>></code></td>
<th class="colSecond" scope="row"><code><span class="memberNameLink"><a href="#iterator()">iterator</a></span>()</code></th>
<td class="colLast">
<div class="block">Returns an iterator over the elements in this deque in proper sequence.</div>
</td>
</tr>
<tr class="altColor" id="i10">
<td class="colFirst"><code>boolean</code></td>
<th class="colSecond" scope="row"><code><span class="memberNameLink"><a href="#offer(E)">offer</a></span>​(<a href="Deque.html" title="type parameter in Deque">E</a> e)</code></th>
<td class="colLast">
<div class="block">Inserts the specified element into the queue represented by this deque
(in other words, at the tail of this deque) if it is possible to do so
immediately without violating capacity restrictions, returning
<code>true</code> upon success and <code>false</code> if no space is currently
available.</div>
</td>
</tr>
<tr class="rowColor" id="i11">
<td class="colFirst"><code>boolean</code></td>
<th class="colSecond" scope="row"><code><span class="memberNameLink"><a href="#offerFirst(E)">offerFirst</a></span>​(<a href="Deque.html" title="type parameter in Deque">E</a> e)</code></th>
<td class="colLast">
<div class="block">Inserts the specified element at the front of this deque unless it would
violate capacity restrictions.</div>
</td>
</tr>
<tr class="altColor" id="i12">
<td class="colFirst"><code>boolean</code></td>
<th class="colSecond" scope="row"><code><span class="memberNameLink"><a href="#offerLast(E)">offerLast</a></span>​(<a href="Deque.html" title="type parameter in Deque">E</a> e)</code></th>
<td class="colLast">
<div class="block">Inserts the specified element at the end of this deque unless it would
violate capacity restrictions.</div>
</td>
</tr>
<tr class="rowColor" id="i13">
<td class="colFirst"><code><a href="Deque.html" title="type parameter in Deque">E</a></code></td>
<th class="colSecond" scope="row"><code><span class="memberNameLink"><a href="#peek()">peek</a></span>()</code></th>
<td class="colLast">
<div class="block">Retrieves, but does not remove, the head of the queue represented by
this deque (in other words, the first element of this deque), or
returns <code>null</code> if this deque is empty.</div>
</td>
</tr>
<tr class="altColor" id="i14">
<td class="colFirst"><code><a href="Deque.html" title="type parameter in Deque">E</a></code></td>
<th class="colSecond" scope="row"><code><span class="memberNameLink"><a href="#peekFirst()">peekFirst</a></span>()</code></th>
<td class="colLast">
<div class="block">Retrieves, but does not remove, the first element of this deque,
or returns <code>null</code> if this deque is empty.</div>
</td>
</tr>
<tr class="rowColor" id="i15">
<td class="colFirst"><code><a href="Deque.html" title="type parameter in Deque">E</a></code></td>
<th class="colSecond" scope="row"><code><span class="memberNameLink"><a href="#peekLast()">peekLast</a></span>()</code></th>
<td class="colLast">
<div class="block">Retrieves, but does not remove, the last element of this deque,
or returns <code>null</code> if this deque is empty.</div>
</td>
</tr>
<tr class="altColor" id="i16">
<td class="colFirst"><code><a href="Deque.html" title="type parameter in Deque">E</a></code></td>
<th class="colSecond" scope="row"><code><span class="memberNameLink"><a href="#poll()">poll</a></span>()</code></th>
<td class="colLast">
<div class="block">Retrieves and removes the head of the queue represented by this deque
(in other words, the first element of this deque), or returns
<code>null</code> if this deque is empty.</div>
</td>
</tr>
<tr class="rowColor" id="i17">
<td class="colFirst"><code><a href="Deque.html" title="type parameter in Deque">E</a></code></td>
<th class="colSecond" scope="row"><code><span class="memberNameLink"><a href="#pollFirst()">pollFirst</a></span>()</code></th>
<td class="colLast">
<div class="block">Retrieves and removes the first element of this deque,
or returns <code>null</code> if this deque is empty.</div>
</td>
</tr>
<tr class="altColor" id="i18">
<td class="colFirst"><code><a href="Deque.html" title="type parameter in Deque">E</a></code></td>
<th class="colSecond" scope="row"><code><span class="memberNameLink"><a href="#pollLast()">pollLast</a></span>()</code></th>
<td class="colLast">
<div class="block">Retrieves and removes the last element of this deque,
or returns <code>null</code> if this deque is empty.</div>
</td>
</tr>
<tr class="rowColor" id="i19">
<td class="colFirst"><code><a href="Deque.html" title="type parameter in Deque">E</a></code></td>
<th class="colSecond" scope="row"><code><span class="memberNameLink"><a href="#pop()">pop</a></span>()</code></th>
<td class="colLast">
<div class="block">Pops an element from the stack represented by this deque.</div>
</td>
</tr>
<tr class="altColor" id="i20">
<td class="colFirst"><code>void</code></td>
<th class="colSecond" scope="row"><code><span class="memberNameLink"><a href="#push(E)">push</a></span>​(<a href="Deque.html" title="type parameter in Deque">E</a> e)</code></th>
<td class="colLast">
<div class="block">Pushes an element onto the stack represented by this deque (in other
words, at the head of this deque) if it is possible to do so
immediately without violating capacity restrictions, throwing an
<code>IllegalStateException</code> if no space is currently available.</div>
</td>
</tr>
<tr class="rowColor" id="i21">
<td class="colFirst"><code><a href="Deque.html" title="type parameter in Deque">E</a></code></td>
<th class="colSecond" scope="row"><code><span class="memberNameLink"><a href="#remove()">remove</a></span>()</code></th>
<td class="colLast">
<div class="block">Retrieves and removes the head of the queue represented by this deque
(in other words, the first element of this deque).</div>
</td>
</tr>
<tr class="altColor" id="i22">
<td class="colFirst"><code>boolean</code></td>
<th class="colSecond" scope="row"><code><span class="memberNameLink"><a href="#remove(java.lang.Object)">remove</a></span>​(<a href="../lang/Object.html" title="class in java.lang">Object</a> o)</code></th>
<td class="colLast">
<div class="block">Removes the first occurrence of the specified element from this deque.</div>
</td>
</tr>
<tr class="rowColor" id="i23">
<td class="colFirst"><code><a href="Deque.html" title="type parameter in Deque">E</a></code></td>
<th class="colSecond" scope="row"><code><span class="memberNameLink"><a href="#removeFirst()">removeFirst</a></span>()</code></th>
<td class="colLast">
<div class="block">Retrieves and removes the first element of this deque.</div>
</td>
</tr>
<tr class="altColor" id="i24">
<td class="colFirst"><code>boolean</code></td>
<th class="colSecond" scope="row"><code><span class="memberNameLink"><a href="#removeFirstOccurrence(java.lang.Object)">removeFirstOccurrence</a></span>​(<a href="../lang/Object.html" title="class in java.lang">Object</a> o)</code></th>
<td class="colLast">
<div class="block">Removes the first occurrence of the specified element from this deque.</div>
</td>
</tr>
<tr class="rowColor" id="i25">
<td class="colFirst"><code><a href="Deque.html" title="type parameter in Deque">E</a></code></td>
<th class="colSecond" scope="row"><code><span class="memberNameLink"><a href="#removeLast()">removeLast</a></span>()</code></th>
<td class="colLast">
<div class="block">Retrieves and removes the last element of this deque.</div>
</td>
</tr>
<tr class="altColor" id="i26">
<td class="colFirst"><code>boolean</code></td>
<th class="colSecond" scope="row"><code><span class="memberNameLink"><a href="#removeLastOccurrence(java.lang.Object)">removeLastOccurrence</a></span>​(<a href="../lang/Object.html" title="class in java.lang">Object</a> o)</code></th>
<td class="colLast">
<div class="block">Removes the last occurrence of the specified element from this deque.</div>
</td>
</tr>
<tr class="rowColor" id="i27">
<td class="colFirst"><code>int</code></td>
<th class="colSecond" scope="row"><code><span class="memberNameLink"><a href="#size()">size</a></span>()</code></th>
<td class="colLast">
<div class="block">Returns the number of elements in this deque.</div>
</td>
</tr>
</tbody>
</table>
</div>
</div>
<ul class="blockList">
<li class="blockList"><a id="methods.inherited.from.class.java.util.Collection">
<!-- -->
</a>
<h3>Methods declared in interface java.util.<a href="Collection.html" title="interface in java.util">Collection</a></h3>
<code><a href="Collection.html#clear()">clear</a>, <a href="Collection.html#containsAll(java.util.Collection)">containsAll</a>, <a href="Collection.html#equals(java.lang.Object)">equals</a>, <a href="Collection.html#hashCode()">hashCode</a>, <a href="Collection.html#isEmpty()">isEmpty</a>, <a href="Collection.html#parallelStream()">parallelStream</a>, <a href="Collection.html#removeAll(java.util.Collection)">removeAll</a>, <a href="Collection.html#removeIf(java.util.function.Predicate)">removeIf</a>, <a href="Collection.html#retainAll(java.util.Collection)">retainAll</a>, <a href="Collection.html#spliterator()">spliterator</a>, <a href="Collection.html#stream()">stream</a>, <a href="Collection.html#toArray()">toArray</a>, <a href="Collection.html#toArray(java.util.function.IntFunction)">toArray</a>, <a href="Collection.html#toArray(T%5B%5D)">toArray</a></code></li>
</ul>
<ul class="blockList">
<li class="blockList"><a id="methods.inherited.from.class.java.lang.Iterable">
<!-- -->
</a>
<h3>Methods declared in interface java.lang.<a href="../lang/Iterable.html" title="interface in java.lang">Iterable</a></h3>
<code><a href="../lang/Iterable.html#forEach(java.util.function.Consumer)">forEach</a></code></li>
</ul>
</li>
</ul>
</section>
</li>
</ul>
</div>
<div class="details">
<ul class="blockList">
<li class="blockList">
<!-- ============ METHOD DETAIL ========== -->
<section role="region">
<ul class="blockList">
<li class="blockList"><a id="method.detail">
<!-- -->
</a>
<h3>Method Detail</h3>
<a id="addFirst(java.lang.Object)">
<!-- -->
</a><a id="addFirst(E)">
<!-- -->
</a>
<ul class="blockList">
<li class="blockList">
<h4>addFirst</h4>
<pre class="methodSignature">void addFirst​(<a href="Deque.html" title="type parameter in Deque">E</a> e)</pre>
<div class="block">Inserts the specified element at the front of this deque if it is
possible to do so immediately without violating capacity restrictions,
throwing an <code>IllegalStateException</code> if no space is currently
available. When using a capacity-restricted deque, it is generally
preferable to use method <a href="#offerFirst(E)"><code>offerFirst(E)</code></a>.</div>
<dl>
<dt><span class="paramLabel">Parameters:</span></dt>
<dd><code>e</code> - the element to add</dd>
<dt><span class="throwsLabel">Throws:</span></dt>
<dd><code><a href="../lang/IllegalStateException.html" title="class in java.lang">IllegalStateException</a></code> - if the element cannot be added at this
time due to capacity restrictions</dd>
<dd><code><a href="../lang/ClassCastException.html" title="class in java.lang">ClassCastException</a></code> - if the class of the specified element
prevents it from being added to this deque</dd>
<dd><code><a href="../lang/NullPointerException.html" title="class in java.lang">NullPointerException</a></code> - if the specified element is null and this
deque does not permit null elements</dd>
<dd><code><a href="../lang/IllegalArgumentException.html" title="class in java.lang">IllegalArgumentException</a></code> - if some property of the specified
element prevents it from being added to this deque</dd>
</dl>
</li>
</ul>
<a id="addLast(java.lang.Object)">
<!-- -->
</a><a id="addLast(E)">
<!-- -->
</a>
<ul class="blockList">
<li class="blockList">
<h4>addLast</h4>
<pre class="methodSignature">void addLast​(<a href="Deque.html" title="type parameter in Deque">E</a> e)</pre>
<div class="block">Inserts the specified element at the end of this deque if it is
possible to do so immediately without violating capacity restrictions,
throwing an <code>IllegalStateException</code> if no space is currently
available. When using a capacity-restricted deque, it is generally
preferable to use method <a href="#offerLast(E)"><code>offerLast(E)</code></a>.
<p>This method is equivalent to <a href="#add(E)"><code>add(E)</code></a>.</div>
<dl>
<dt><span class="paramLabel">Parameters:</span></dt>
<dd><code>e</code> - the element to add</dd>
<dt><span class="throwsLabel">Throws:</span></dt>
<dd><code><a href="../lang/IllegalStateException.html" title="class in java.lang">IllegalStateException</a></code> - if the element cannot be added at this
time due to capacity restrictions</dd>
<dd><code><a href="../lang/ClassCastException.html" title="class in java.lang">ClassCastException</a></code> - if the class of the specified element
prevents it from being added to this deque</dd>
<dd><code><a href="../lang/NullPointerException.html" title="class in java.lang">NullPointerException</a></code> - if the specified element is null and this
deque does not permit null elements</dd>
<dd><code><a href="../lang/IllegalArgumentException.html" title="class in java.lang">IllegalArgumentException</a></code> - if some property of the specified
element prevents it from being added to this deque</dd>
</dl>
</li>
</ul>
<a id="offerFirst(java.lang.Object)">
<!-- -->
</a><a id="offerFirst(E)">
<!-- -->
</a>
<ul class="blockList">
<li class="blockList">
<h4>offerFirst</h4>
<pre class="methodSignature">boolean offerFirst​(<a href="Deque.html" title="type parameter in Deque">E</a> e)</pre>
<div class="block">Inserts the specified element at the front of this deque unless it would
violate capacity restrictions. When using a capacity-restricted deque,
this method is generally preferable to the <a href="#addFirst(E)"><code>addFirst(E)</code></a> method,
which can fail to insert an element only by throwing an exception.</div>
<dl>
<dt><span class="paramLabel">Parameters:</span></dt>
<dd><code>e</code> - the element to add</dd>
<dt><span class="returnLabel">Returns:</span></dt>
<dd><code>true</code> if the element was added to this deque, else
<code>false</code></dd>
<dt><span class="throwsLabel">Throws:</span></dt>
<dd><code><a href="../lang/ClassCastException.html" title="class in java.lang">ClassCastException</a></code> - if the class of the specified element
prevents it from being added to this deque</dd>
<dd><code><a href="../lang/NullPointerException.html" title="class in java.lang">NullPointerException</a></code> - if the specified element is null and this
deque does not permit null elements</dd>
<dd><code><a href="../lang/IllegalArgumentException.html" title="class in java.lang">IllegalArgumentException</a></code> - if some property of the specified
element prevents it from being added to this deque</dd>
</dl>
</li>
</ul>
<a id="offerLast(java.lang.Object)">
<!-- -->
</a><a id="offerLast(E)">
<!-- -->
</a>
<ul class="blockList">
<li class="blockList">
<h4>offerLast</h4>
<pre class="methodSignature">boolean offerLast​(<a href="Deque.html" title="type parameter in Deque">E</a> e)</pre>
<div class="block">Inserts the specified element at the end of this deque unless it would
violate capacity restrictions. When using a capacity-restricted deque,
this method is generally preferable to the <a href="#addLast(E)"><code>addLast(E)</code></a> method,
which can fail to insert an element only by throwing an exception.</div>
<dl>
<dt><span class="paramLabel">Parameters:</span></dt>
<dd><code>e</code> - the element to add</dd>
<dt><span class="returnLabel">Returns:</span></dt>
<dd><code>true</code> if the element was added to this deque, else
<code>false</code></dd>
<dt><span class="throwsLabel">Throws:</span></dt>
<dd><code><a href="../lang/ClassCastException.html" title="class in java.lang">ClassCastException</a></code> - if the class of the specified element
prevents it from being added to this deque</dd>
<dd><code><a href="../lang/NullPointerException.html" title="class in java.lang">NullPointerException</a></code> - if the specified element is null and this
deque does not permit null elements</dd>
<dd><code><a href="../lang/IllegalArgumentException.html" title="class in java.lang">IllegalArgumentException</a></code> - if some property of the specified
element prevents it from being added to this deque</dd>
</dl>
</li>
</ul>
<a id="removeFirst()">
<!-- -->
</a>
<ul class="blockList">
<li class="blockList">
<h4>removeFirst</h4>
<pre class="methodSignature"><a href="Deque.html" title="type parameter in Deque">E</a> removeFirst()</pre>
<div class="block">Retrieves and removes the first element of this deque. This method
differs from <a href="#pollFirst()"><code>pollFirst</code></a> only in that it throws an
exception if this deque is empty.</div>
<dl>
<dt><span class="returnLabel">Returns:</span></dt>
<dd>the head of this deque</dd>
<dt><span class="throwsLabel">Throws:</span></dt>
<dd><code><a href="NoSuchElementException.html" title="class in java.util">NoSuchElementException</a></code> - if this deque is empty</dd>
</dl>
</li>
</ul>
<a id="removeLast()">
<!-- -->
</a>
<ul class="blockList">
<li class="blockList">
<h4>removeLast</h4>
<pre class="methodSignature"><a href="Deque.html" title="type parameter in Deque">E</a> removeLast()</pre>
<div class="block">Retrieves and removes the last element of this deque. This method
differs from <a href="#pollLast()"><code>pollLast</code></a> only in that it throws an
exception if this deque is empty.</div>
<dl>
<dt><span class="returnLabel">Returns:</span></dt>
<dd>the tail of this deque</dd>
<dt><span class="throwsLabel">Throws:</span></dt>
<dd><code><a href="NoSuchElementException.html" title="class in java.util">NoSuchElementException</a></code> - if this deque is empty</dd>
</dl>
</li>
</ul>
<a id="pollFirst()">
<!-- -->
</a>
<ul class="blockList">
<li class="blockList">
<h4>pollFirst</h4>
<pre class="methodSignature"><a href="Deque.html" title="type parameter in Deque">E</a> pollFirst()</pre>
<div class="block">Retrieves and removes the first element of this deque,
or returns <code>null</code> if this deque is empty.</div>
<dl>
<dt><span class="returnLabel">Returns:</span></dt>
<dd>the head of this deque, or <code>null</code> if this deque is empty</dd>
</dl>
</li>
</ul>
<a id="pollLast()">
<!-- -->
</a>
<ul class="blockList">
<li class="blockList">
<h4>pollLast</h4>
<pre class="methodSignature"><a href="Deque.html" title="type parameter in Deque">E</a> pollLast()</pre>
<div class="block">Retrieves and removes the last element of this deque,
or returns <code>null</code> if this deque is empty.</div>
<dl>
<dt><span class="returnLabel">Returns:</span></dt>
<dd>the tail of this deque, or <code>null</code> if this deque is empty</dd>
</dl>
</li>
</ul>
<a id="getFirst()">
<!-- -->
</a>
<ul class="blockList">
<li class="blockList">
<h4>getFirst</h4>
<pre class="methodSignature"><a href="Deque.html" title="type parameter in Deque">E</a> getFirst()</pre>
<div class="block">Retrieves, but does not remove, the first element of this deque.
This method differs from <a href="#peekFirst()"><code>peekFirst</code></a> only in that it
throws an exception if this deque is empty.</div>
<dl>
<dt><span class="returnLabel">Returns:</span></dt>
<dd>the head of this deque</dd>
<dt><span class="throwsLabel">Throws:</span></dt>
<dd><code><a href="NoSuchElementException.html" title="class in java.util">NoSuchElementException</a></code> - if this deque is empty</dd>
</dl>
</li>
</ul>
<a id="getLast()">
<!-- -->
</a>
<ul class="blockList">
<li class="blockList">
<h4>getLast</h4>
<pre class="methodSignature"><a href="Deque.html" title="type parameter in Deque">E</a> getLast()</pre>
<div class="block">Retrieves, but does not remove, the last element of this deque.
This method differs from <a href="#peekLast()"><code>peekLast</code></a> only in that it
throws an exception if this deque is empty.</div>
<dl>
<dt><span class="returnLabel">Returns:</span></dt>
<dd>the tail of this deque</dd>
<dt><span class="throwsLabel">Throws:</span></dt>
<dd><code><a href="NoSuchElementException.html" title="class in java.util">NoSuchElementException</a></code> - if this deque is empty</dd>
</dl>
</li>
</ul>
<a id="peekFirst()">
<!-- -->
</a>
<ul class="blockList">
<li class="blockList">
<h4>peekFirst</h4>
<pre class="methodSignature"><a href="Deque.html" title="type parameter in Deque">E</a> peekFirst()</pre>
<div class="block">Retrieves, but does not remove, the first element of this deque,
or returns <code>null</code> if this deque is empty.</div>
<dl>
<dt><span class="returnLabel">Returns:</span></dt>
<dd>the head of this deque, or <code>null</code> if this deque is empty</dd>
</dl>
</li>
</ul>
<a id="peekLast()">
<!-- -->
</a>
<ul class="blockList">
<li class="blockList">
<h4>peekLast</h4>
<pre class="methodSignature"><a href="Deque.html" title="type parameter in Deque">E</a> peekLast()</pre>
<div class="block">Retrieves, but does not remove, the last element of this deque,
or returns <code>null</code> if this deque is empty.</div>
<dl>
<dt><span class="returnLabel">Returns:</span></dt>
<dd>the tail of this deque, or <code>null</code> if this deque is empty</dd>
</dl>
</li>
</ul>
<a id="removeFirstOccurrence(java.lang.Object)">
<!-- -->
</a>
<ul class="blockList">
<li class="blockList">
<h4>removeFirstOccurrence</h4>
<pre class="methodSignature">boolean removeFirstOccurrence​(<a href="../lang/Object.html" title="class in java.lang">Object</a> o)</pre>
<div class="block">Removes the first occurrence of the specified element from this deque.
If the deque does not contain the element, it is unchanged.
More formally, removes the first element <code>e</code> such that
<code>Objects.equals(o, e)</code> (if such an element exists).
Returns <code>true</code> if this deque contained the specified element
(or equivalently, if this deque changed as a result of the call).</div>
<dl>
<dt><span class="paramLabel">Parameters:</span></dt>
<dd><code>o</code> - element to be removed from this deque, if present</dd>
<dt><span class="returnLabel">Returns:</span></dt>
<dd><code>true</code> if an element was removed as a result of this call</dd>
<dt><span class="throwsLabel">Throws:</span></dt>
<dd><code><a href="../lang/ClassCastException.html" title="class in java.lang">ClassCastException</a></code> - if the class of the specified element
is incompatible with this deque
(<a href="../../../java.base/java/util/Collection.html#optional-restrictions">optional</a>)</dd>
<dd><code><a href="../lang/NullPointerException.html" title="class in java.lang">NullPointerException</a></code> - if the specified element is null and this
deque does not permit null elements
(<a href="../../../java.base/java/util/Collection.html#optional-restrictions">optional</a>)</dd>
</dl>
</li>
</ul>
<a id="removeLastOccurrence(java.lang.Object)">
<!-- -->
</a>
<ul class="blockList">
<li class="blockList">
<h4>removeLastOccurrence</h4>
<pre class="methodSignature">boolean removeLastOccurrence​(<a href="../lang/Object.html" title="class in java.lang">Object</a> o)</pre>
<div class="block">Removes the last occurrence of the specified element from this deque.
If the deque does not contain the element, it is unchanged.
More formally, removes the last element <code>e</code> such that
<code>Objects.equals(o, e)</code> (if such an element exists).
Returns <code>true</code> if this deque contained the specified element
(or equivalently, if this deque changed as a result of the call).</div>
<dl>
<dt><span class="paramLabel">Parameters:</span></dt>
<dd><code>o</code> - element to be removed from this deque, if present</dd>
<dt><span class="returnLabel">Returns:</span></dt>
<dd><code>true</code> if an element was removed as a result of this call</dd>
<dt><span class="throwsLabel">Throws:</span></dt>
<dd><code><a href="../lang/ClassCastException.html" title="class in java.lang">ClassCastException</a></code> - if the class of the specified element
is incompatible with this deque
(<a href="../../../java.base/java/util/Collection.html#optional-restrictions">optional</a>)</dd>
<dd><code><a href="../lang/NullPointerException.html" title="class in java.lang">NullPointerException</a></code> - if the specified element is null and this
deque does not permit null elements
(<a href="../../../java.base/java/util/Collection.html#optional-restrictions">optional</a>)</dd>
</dl>
</li>
</ul>
<a id="add(java.lang.Object)">
<!-- -->
</a><a id="add(E)">
<!-- -->
</a>
<ul class="blockList">
<li class="blockList">
<h4>add</h4>
<pre class="methodSignature">boolean add​(<a href="Deque.html" title="type parameter in Deque">E</a> e)</pre>
<div class="block">Inserts the specified element into the queue represented by this deque
(in other words, at the tail of this deque) if it is possible to do so
immediately without violating capacity restrictions, returning
<code>true</code> upon success and throwing an
<code>IllegalStateException</code> if no space is currently available.
When using a capacity-restricted deque, it is generally preferable to
use <a href="#offer(E)"><code>offer</code></a>.
<p>This method is equivalent to <a href="#addLast(E)"><code>addLast(E)</code></a>.</div>
<dl>
<dt><span class="overrideSpecifyLabel">Specified by:</span></dt>
<dd><code><a href="Collection.html#add(E)">add</a></code> in interface <code><a href="Collection.html" title="interface in java.util">Collection</a><<a href="Deque.html" title="type parameter in Deque">E</a>></code></dd>
<dt><span class="overrideSpecifyLabel">Specified by:</span></dt>
<dd><code><a href="Queue.html#add(E)">add</a></code> in interface <code><a href="Queue.html" title="interface in java.util">Queue</a><<a href="Deque.html" title="type parameter in Deque">E</a>></code></dd>
<dt><span class="paramLabel">Parameters:</span></dt>
<dd><code>e</code> - the element to add</dd>
<dt><span class="returnLabel">Returns:</span></dt>
<dd><code>true</code> (as specified by <a href="Collection.html#add(E)"><code>Collection.add(E)</code></a>)</dd>
<dt><span class="throwsLabel">Throws:</span></dt>
<dd><code><a href="../lang/IllegalStateException.html" title="class in java.lang">IllegalStateException</a></code> - if the element cannot be added at this
time due to capacity restrictions</dd>
<dd><code><a href="../lang/ClassCastException.html" title="class in java.lang">ClassCastException</a></code> - if the class of the specified element
prevents it from being added to this deque</dd>
<dd><code><a href="../lang/NullPointerException.html" title="class in java.lang">NullPointerException</a></code> - if the specified element is null and this
deque does not permit null elements</dd>
<dd><code><a href="../lang/IllegalArgumentException.html" title="class in java.lang">IllegalArgumentException</a></code> - if some property of the specified
element prevents it from being added to this deque</dd>
</dl>
</li>
</ul>
<a id="offer(java.lang.Object)">
<!-- -->
</a><a id="offer(E)">
<!-- -->
</a>
<ul class="blockList">
<li class="blockList">
<h4>offer</h4>
<pre class="methodSignature">boolean offer​(<a href="Deque.html" title="type parameter in Deque">E</a> e)</pre>
<div class="block">Inserts the specified element into the queue represented by this deque
(in other words, at the tail of this deque) if it is possible to do so
immediately without violating capacity restrictions, returning
<code>true</code> upon success and <code>false</code> if no space is currently
available. When using a capacity-restricted deque, this method is
generally preferable to the <a href="#add(E)"><code>add(E)</code></a> method, which can fail to
insert an element only by throwing an exception.
<p>This method is equivalent to <a href="#offerLast(E)"><code>offerLast(E)</code></a>.</div>
<dl>
<dt><span class="overrideSpecifyLabel">Specified by:</span></dt>
<dd><code><a href="Queue.html#offer(E)">offer</a></code> in interface <code><a href="Queue.html" title="interface in java.util">Queue</a><<a href="Deque.html" title="type parameter in Deque">E</a>></code></dd>
<dt><span class="paramLabel">Parameters:</span></dt>
<dd><code>e</code> - the element to add</dd>
<dt><span class="returnLabel">Returns:</span></dt>
<dd><code>true</code> if the element was added to this deque, else
<code>false</code></dd>
<dt><span class="throwsLabel">Throws:</span></dt>
<dd><code><a href="../lang/ClassCastException.html" title="class in java.lang">ClassCastException</a></code> - if the class of the specified element
prevents it from being added to this deque</dd>
<dd><code><a href="../lang/NullPointerException.html" title="class in java.lang">NullPointerException</a></code> - if the specified element is null and this
deque does not permit null elements</dd>
<dd><code><a href="../lang/IllegalArgumentException.html" title="class in java.lang">IllegalArgumentException</a></code> - if some property of the specified
element prevents it from being added to this deque</dd>
</dl>
</li>
</ul>
<a id="remove()">
<!-- -->
</a>
<ul class="blockList">
<li class="blockList">
<h4>remove</h4>
<pre class="methodSignature"><a href="Deque.html" title="type parameter in Deque">E</a> remove()</pre>
<div class="block">Retrieves and removes the head of the queue represented by this deque
(in other words, the first element of this deque).
This method differs from <a href="#poll()"><code>poll()</code></a> only in that it
throws an exception if this deque is empty.