1 |
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/* |
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* %W% %E% |
3 |
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* |
4 |
< |
* Copyright 2003 Sun Microsystems, Inc. All rights reserved. |
4 |
> |
* Copyright 2004 Sun Microsystems, Inc. All rights reserved. |
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* SUN PROPRIETARY/CONFIDENTIAL. Use is subject to license terms. |
6 |
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*/ |
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|
63 |
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* |
64 |
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* @author Josh Bloch |
65 |
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* @version %I%, %G% |
66 |
< |
* @see List |
67 |
< |
* @see ArrayList |
68 |
< |
* @see Vector |
69 |
< |
* @see Collections#synchronizedList(List) |
66 |
> |
* @see List |
67 |
> |
* @see ArrayList |
68 |
> |
* @see Vector |
69 |
> |
* @see Collections#synchronizedList(List) |
70 |
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* @since 1.2 |
71 |
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* @param <E> the type of elements held in this collection |
72 |
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*/ |
93 |
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* @param c the collection whose elements are to be placed into this list. |
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* @throws NullPointerException if the specified collection is null. |
95 |
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*/ |
96 |
< |
public LinkedList(Collection<? extends E> c) { |
97 |
< |
this(); |
98 |
< |
addAll(c); |
99 |
< |
} |
96 |
> |
public LinkedList(Collection<? extends E> c) { |
97 |
> |
this(); |
98 |
> |
addAll(c); |
99 |
> |
} |
100 |
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|
101 |
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/** |
102 |
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* Returns the first element in this list. |
105 |
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* @throws NoSuchElementException if this list is empty. |
106 |
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*/ |
107 |
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public E getFirst() { |
108 |
< |
if (size==0) |
109 |
< |
throw new NoSuchElementException(); |
108 |
> |
if (size==0) |
109 |
> |
throw new NoSuchElementException(); |
110 |
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|
111 |
< |
return header.next.element; |
111 |
> |
return header.next.element; |
112 |
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} |
113 |
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|
114 |
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/** |
118 |
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* @throws NoSuchElementException if this list is empty. |
119 |
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*/ |
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public E getLast() { |
121 |
< |
if (size==0) |
122 |
< |
throw new NoSuchElementException(); |
121 |
> |
if (size==0) |
122 |
> |
throw new NoSuchElementException(); |
123 |
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|
124 |
< |
return header.previous.element; |
124 |
> |
return header.previous.element; |
125 |
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} |
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|
127 |
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/** |
131 |
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* @throws NoSuchElementException if this list is empty. |
132 |
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*/ |
133 |
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public E removeFirst() { |
134 |
< |
E first = header.next.element; |
135 |
< |
remove(header.next); |
136 |
< |
return first; |
134 |
> |
return remove(header.next); |
135 |
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} |
136 |
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|
137 |
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/** |
141 |
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* @throws NoSuchElementException if this list is empty. |
142 |
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*/ |
143 |
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public E removeLast() { |
144 |
< |
E last = header.previous.element; |
147 |
< |
remove(header.previous); |
148 |
< |
return last; |
144 |
> |
return remove(header.previous); |
145 |
|
} |
146 |
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|
147 |
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/** |
150 |
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* @param o the element to be inserted at the beginning of this list. |
151 |
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*/ |
152 |
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public void addFirst(E o) { |
153 |
< |
addBefore(o, header.next); |
153 |
> |
addBefore(o, header.next); |
154 |
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} |
155 |
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|
156 |
|
/** |
160 |
|
* @param o the element to be inserted at the end of this list. |
161 |
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*/ |
162 |
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public void addLast(E o) { |
163 |
< |
addBefore(o, header); |
163 |
> |
addBefore(o, header); |
164 |
|
} |
165 |
|
|
166 |
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/** |
182 |
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* @return the number of elements in this list. |
183 |
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*/ |
184 |
|
public int size() { |
185 |
< |
return size; |
185 |
> |
return size; |
186 |
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} |
187 |
|
|
188 |
|
/** |
193 |
|
* <tt>Collection.add</tt>). |
194 |
|
*/ |
195 |
|
public boolean add(E o) { |
196 |
< |
addBefore(o, header); |
196 |
> |
addBefore(o, header); |
197 |
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return true; |
198 |
|
} |
199 |
|
|
251 |
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* specified collection's iterator. |
252 |
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* |
253 |
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* @param index index at which to insert first element |
254 |
< |
* from the specified collection. |
254 |
> |
* from the specified collection. |
255 |
|
* @param c elements to be inserted into this list. |
256 |
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* @return <tt>true</tt> if this list changed as a result of the call. |
257 |
|
* @throws IndexOutOfBoundsException if the specified index is out of |
266 |
|
int numNew = a.length; |
267 |
|
if (numNew==0) |
268 |
|
return false; |
269 |
< |
modCount++; |
269 |
> |
modCount++; |
270 |
|
|
271 |
|
Entry<E> successor = (index==size ? header : entry(index)); |
272 |
|
Entry<E> predecessor = successor.previous; |
273 |
< |
for (int i=0; i<numNew; i++) { |
273 |
> |
for (int i=0; i<numNew; i++) { |
274 |
|
Entry<E> e = new Entry<E>((E)a[i], successor, predecessor); |
275 |
|
predecessor.next = e; |
276 |
|
predecessor = e; |
285 |
|
* Removes all of the elements from this list. |
286 |
|
*/ |
287 |
|
public void clear() { |
288 |
< |
modCount++; |
288 |
> |
Entry<E> e = header.next; |
289 |
> |
while (e != header) { |
290 |
> |
Entry<E> next = e.next; |
291 |
> |
e.next = e.previous = null; |
292 |
> |
e.element = null; |
293 |
> |
e = next; |
294 |
> |
} |
295 |
|
header.next = header.previous = header; |
296 |
|
size = 0; |
297 |
+ |
modCount++; |
298 |
|
} |
299 |
|
|
300 |
|
|
306 |
|
* @param index index of element to return. |
307 |
|
* @return the element at the specified position in this list. |
308 |
|
* |
309 |
< |
* @throws IndexOutOfBoundsException if the specified index is is out of |
309 |
> |
* @throws IndexOutOfBoundsException if the specified index is out of |
310 |
|
* range (<tt>index < 0 || index >= size()</tt>). |
311 |
|
*/ |
312 |
|
public E get(int index) { |
321 |
|
* @param element element to be stored at the specified position. |
322 |
|
* @return the element previously at the specified position. |
323 |
|
* @throws IndexOutOfBoundsException if the specified index is out of |
324 |
< |
* range (<tt>index < 0 || index >= size()</tt>). |
324 |
> |
* range (<tt>index < 0 || index >= size()</tt>). |
325 |
|
*/ |
326 |
|
public E set(int index, E element) { |
327 |
|
Entry<E> e = entry(index); |
339 |
|
* @param element element to be inserted. |
340 |
|
* |
341 |
|
* @throws IndexOutOfBoundsException if the specified index is out of |
342 |
< |
* range (<tt>index < 0 || index > size()</tt>). |
342 |
> |
* range (<tt>index < 0 || index > size()</tt>). |
343 |
|
*/ |
344 |
|
public void add(int index, E element) { |
345 |
|
addBefore(element, (index==size ? header : entry(index))); |
354 |
|
* @return the element previously at the specified position. |
355 |
|
* |
356 |
|
* @throws IndexOutOfBoundsException if the specified index is out of |
357 |
< |
* range (<tt>index < 0 || index >= size()</tt>). |
357 |
> |
* range (<tt>index < 0 || index >= size()</tt>). |
358 |
|
*/ |
359 |
|
public E remove(int index) { |
360 |
< |
Entry<E> e = entry(index); |
358 |
< |
remove(e); |
359 |
< |
return e.element; |
360 |
> |
return remove(entry(index)); |
361 |
|
} |
362 |
|
|
363 |
|
/** |
390 |
|
* |
391 |
|
* @param o element to search for. |
392 |
|
* @return the index in this list of the first occurrence of the |
393 |
< |
* specified element, or -1 if the list does not contain this |
394 |
< |
* element. |
393 |
> |
* specified element, or -1 if the list does not contain this |
394 |
> |
* element. |
395 |
|
*/ |
396 |
|
public int indexOf(Object o) { |
397 |
|
int index = 0; |
420 |
|
* |
421 |
|
* @param o element to search for. |
422 |
|
* @return the index in this list of the last occurrence of the |
423 |
< |
* specified element, or -1 if the list does not contain this |
424 |
< |
* element. |
423 |
> |
* specified element, or -1 if the list does not contain this |
424 |
> |
* element. |
425 |
|
*/ |
426 |
|
public int lastIndexOf(Object o) { |
427 |
|
int index = size; |
512 |
|
* time in the future. |
513 |
|
* |
514 |
|
* @param index index of first element to be returned from the |
515 |
< |
* list-iterator (by a call to <tt>next</tt>). |
515 |
> |
* list-iterator (by a call to <tt>next</tt>). |
516 |
|
* @return a ListIterator of the elements in this list (in proper |
517 |
< |
* sequence), starting at the specified position in the list. |
517 |
> |
* sequence), starting at the specified position in the list. |
518 |
|
* @throws IndexOutOfBoundsException if index is out of range |
519 |
< |
* (<tt>index < 0 || index > size()</tt>). |
519 |
> |
* (<tt>index < 0 || index > size()</tt>). |
520 |
|
* @see List#listIterator(int) |
521 |
|
*/ |
522 |
|
public ListIterator<E> listIterator(int index) { |
523 |
< |
return new ListItr(index); |
523 |
> |
return new ListItr(index); |
524 |
|
} |
525 |
|
|
526 |
|
private class ListItr implements ListIterator<E> { |
527 |
< |
private Entry<E> lastReturned = header; |
528 |
< |
private Entry<E> next; |
529 |
< |
private int nextIndex; |
530 |
< |
private int expectedModCount = modCount; |
531 |
< |
|
532 |
< |
ListItr(int index) { |
533 |
< |
if (index < 0 || index > size) |
534 |
< |
throw new IndexOutOfBoundsException("Index: "+index+ |
535 |
< |
", Size: "+size); |
536 |
< |
if (index < (size >> 1)) { |
537 |
< |
next = header.next; |
538 |
< |
for (nextIndex=0; nextIndex<index; nextIndex++) |
539 |
< |
next = next.next; |
540 |
< |
} else { |
541 |
< |
next = header; |
542 |
< |
for (nextIndex=size; nextIndex>index; nextIndex--) |
543 |
< |
next = next.previous; |
544 |
< |
} |
545 |
< |
} |
546 |
< |
|
547 |
< |
public boolean hasNext() { |
548 |
< |
return nextIndex != size; |
549 |
< |
} |
550 |
< |
|
551 |
< |
public E next() { |
552 |
< |
checkForComodification(); |
553 |
< |
if (nextIndex == size) |
554 |
< |
throw new NoSuchElementException(); |
555 |
< |
|
556 |
< |
lastReturned = next; |
557 |
< |
next = next.next; |
558 |
< |
nextIndex++; |
559 |
< |
return lastReturned.element; |
560 |
< |
} |
527 |
> |
private Entry<E> lastReturned = header; |
528 |
> |
private Entry<E> next; |
529 |
> |
private int nextIndex; |
530 |
> |
private int expectedModCount = modCount; |
531 |
> |
|
532 |
> |
ListItr(int index) { |
533 |
> |
if (index < 0 || index > size) |
534 |
> |
throw new IndexOutOfBoundsException("Index: "+index+ |
535 |
> |
", Size: "+size); |
536 |
> |
if (index < (size >> 1)) { |
537 |
> |
next = header.next; |
538 |
> |
for (nextIndex=0; nextIndex<index; nextIndex++) |
539 |
> |
next = next.next; |
540 |
> |
} else { |
541 |
> |
next = header; |
542 |
> |
for (nextIndex=size; nextIndex>index; nextIndex--) |
543 |
> |
next = next.previous; |
544 |
> |
} |
545 |
> |
} |
546 |
> |
|
547 |
> |
public boolean hasNext() { |
548 |
> |
return nextIndex != size; |
549 |
> |
} |
550 |
> |
|
551 |
> |
public E next() { |
552 |
> |
checkForComodification(); |
553 |
> |
if (nextIndex == size) |
554 |
> |
throw new NoSuchElementException(); |
555 |
> |
|
556 |
> |
lastReturned = next; |
557 |
> |
next = next.next; |
558 |
> |
nextIndex++; |
559 |
> |
return lastReturned.element; |
560 |
> |
} |
561 |
> |
|
562 |
> |
public boolean hasPrevious() { |
563 |
> |
return nextIndex != 0; |
564 |
> |
} |
565 |
> |
|
566 |
> |
public E previous() { |
567 |
> |
if (nextIndex == 0) |
568 |
> |
throw new NoSuchElementException(); |
569 |
> |
|
570 |
> |
lastReturned = next = next.previous; |
571 |
> |
nextIndex--; |
572 |
> |
checkForComodification(); |
573 |
> |
return lastReturned.element; |
574 |
> |
} |
575 |
> |
|
576 |
> |
public int nextIndex() { |
577 |
> |
return nextIndex; |
578 |
> |
} |
579 |
> |
|
580 |
> |
public int previousIndex() { |
581 |
> |
return nextIndex-1; |
582 |
> |
} |
583 |
|
|
584 |
< |
public boolean hasPrevious() { |
562 |
< |
return nextIndex != 0; |
563 |
< |
} |
564 |
< |
|
565 |
< |
public E previous() { |
566 |
< |
if (nextIndex == 0) |
567 |
< |
throw new NoSuchElementException(); |
568 |
< |
|
569 |
< |
lastReturned = next = next.previous; |
570 |
< |
nextIndex--; |
571 |
< |
checkForComodification(); |
572 |
< |
return lastReturned.element; |
573 |
< |
} |
574 |
< |
|
575 |
< |
public int nextIndex() { |
576 |
< |
return nextIndex; |
577 |
< |
} |
578 |
< |
|
579 |
< |
public int previousIndex() { |
580 |
< |
return nextIndex-1; |
581 |
< |
} |
582 |
< |
|
583 |
< |
public void remove() { |
584 |
> |
public void remove() { |
585 |
|
checkForComodification(); |
586 |
+ |
Entry<E> lastNext = lastReturned.next; |
587 |
|
try { |
588 |
|
LinkedList.this.remove(lastReturned); |
589 |
|
} catch (NoSuchElementException e) { |
590 |
|
throw new IllegalStateException(); |
591 |
|
} |
592 |
< |
if (next==lastReturned) |
593 |
< |
next = lastReturned.next; |
592 |
> |
if (next==lastReturned) |
593 |
> |
next = lastNext; |
594 |
|
else |
595 |
< |
nextIndex--; |
596 |
< |
lastReturned = header; |
597 |
< |
expectedModCount++; |
598 |
< |
} |
599 |
< |
|
600 |
< |
public void set(E o) { |
601 |
< |
if (lastReturned == header) |
602 |
< |
throw new IllegalStateException(); |
603 |
< |
checkForComodification(); |
604 |
< |
lastReturned.element = o; |
605 |
< |
} |
606 |
< |
|
607 |
< |
public void add(E o) { |
608 |
< |
checkForComodification(); |
609 |
< |
lastReturned = header; |
610 |
< |
addBefore(o, next); |
611 |
< |
nextIndex++; |
612 |
< |
expectedModCount++; |
613 |
< |
} |
614 |
< |
|
615 |
< |
final void checkForComodification() { |
616 |
< |
if (modCount != expectedModCount) |
617 |
< |
throw new ConcurrentModificationException(); |
618 |
< |
} |
595 |
> |
nextIndex--; |
596 |
> |
lastReturned = header; |
597 |
> |
expectedModCount++; |
598 |
> |
} |
599 |
> |
|
600 |
> |
public void set(E o) { |
601 |
> |
if (lastReturned == header) |
602 |
> |
throw new IllegalStateException(); |
603 |
> |
checkForComodification(); |
604 |
> |
lastReturned.element = o; |
605 |
> |
} |
606 |
> |
|
607 |
> |
public void add(E o) { |
608 |
> |
checkForComodification(); |
609 |
> |
lastReturned = header; |
610 |
> |
addBefore(o, next); |
611 |
> |
nextIndex++; |
612 |
> |
expectedModCount++; |
613 |
> |
} |
614 |
> |
|
615 |
> |
final void checkForComodification() { |
616 |
> |
if (modCount != expectedModCount) |
617 |
> |
throw new ConcurrentModificationException(); |
618 |
> |
} |
619 |
|
} |
620 |
|
|
621 |
|
private static class Entry<E> { |
622 |
< |
E element; |
623 |
< |
Entry<E> next; |
624 |
< |
Entry<E> previous; |
625 |
< |
|
626 |
< |
Entry(E element, Entry<E> next, Entry<E> previous) { |
627 |
< |
this.element = element; |
628 |
< |
this.next = next; |
629 |
< |
this.previous = previous; |
630 |
< |
} |
622 |
> |
E element; |
623 |
> |
Entry<E> next; |
624 |
> |
Entry<E> previous; |
625 |
> |
|
626 |
> |
Entry(E element, Entry<E> next, Entry<E> previous) { |
627 |
> |
this.element = element; |
628 |
> |
this.next = next; |
629 |
> |
this.previous = previous; |
630 |
> |
} |
631 |
|
} |
632 |
|
|
633 |
|
private Entry<E> addBefore(E o, Entry<E> e) { |
634 |
< |
Entry<E> newEntry = new Entry<E>(o, e, e.previous); |
635 |
< |
newEntry.previous.next = newEntry; |
636 |
< |
newEntry.next.previous = newEntry; |
637 |
< |
size++; |
638 |
< |
modCount++; |
639 |
< |
return newEntry; |
640 |
< |
} |
641 |
< |
|
642 |
< |
private void remove(Entry<E> e) { |
643 |
< |
if (e == header) |
644 |
< |
throw new NoSuchElementException(); |
645 |
< |
|
646 |
< |
e.previous.next = e.next; |
647 |
< |
e.next.previous = e.previous; |
648 |
< |
size--; |
649 |
< |
modCount++; |
634 |
> |
Entry<E> newEntry = new Entry<E>(o, e, e.previous); |
635 |
> |
newEntry.previous.next = newEntry; |
636 |
> |
newEntry.next.previous = newEntry; |
637 |
> |
size++; |
638 |
> |
modCount++; |
639 |
> |
return newEntry; |
640 |
> |
} |
641 |
> |
|
642 |
> |
private E remove(Entry<E> e) { |
643 |
> |
if (e == header) |
644 |
> |
throw new NoSuchElementException(); |
645 |
> |
|
646 |
> |
E result = e.element; |
647 |
> |
e.previous.next = e.next; |
648 |
> |
e.next.previous = e.previous; |
649 |
> |
e.next = e.previous = null; |
650 |
> |
e.element = null; |
651 |
> |
size--; |
652 |
> |
modCount++; |
653 |
> |
return result; |
654 |
|
} |
655 |
|
|
656 |
|
/** |
661 |
|
*/ |
662 |
|
public Object clone() { |
663 |
|
LinkedList<E> clone = null; |
664 |
< |
try { |
665 |
< |
clone = (LinkedList<E>) super.clone(); |
666 |
< |
} catch (CloneNotSupportedException e) { |
667 |
< |
throw new InternalError(); |
668 |
< |
} |
664 |
> |
try { |
665 |
> |
clone = (LinkedList<E>) super.clone(); |
666 |
> |
} catch (CloneNotSupportedException e) { |
667 |
> |
throw new InternalError(); |
668 |
> |
} |
669 |
|
|
670 |
|
// Put clone into "virgin" state |
671 |
|
clone.header = new Entry<E>(null, null, null); |
685 |
|
* in the correct order. |
686 |
|
* |
687 |
|
* @return an array containing all of the elements in this list |
688 |
< |
* in the correct order. |
688 |
> |
* in the correct order. |
689 |
|
*/ |
690 |
|
public Object[] toArray() { |
691 |
< |
Object[] result = new Object[size]; |
691 |
> |
Object[] result = new Object[size]; |
692 |
|
int i = 0; |
693 |
|
for (Entry<E> e = header.next; e != header; e = e.next) |
694 |
|
result[i++] = e.element; |
695 |
< |
return result; |
695 |
> |
return result; |
696 |
|
} |
697 |
|
|
698 |
|
/** |
710 |
|
* does not contain any null elements. |
711 |
|
* |
712 |
|
* @param a the array into which the elements of the list are to |
713 |
< |
* be stored, if it is big enough; otherwise, a new array of the |
714 |
< |
* same runtime type is allocated for this purpose. |
713 |
> |
* be stored, if it is big enough; otherwise, a new array of the |
714 |
> |
* same runtime type is allocated for this purpose. |
715 |
|
* @return an array containing the elements of the list. |
716 |
|
* @throws ArrayStoreException if the runtime type of a is not a |
717 |
|
* supertype of the runtime type of every element in this list. |
722 |
|
a = (T[])java.lang.reflect.Array.newInstance( |
723 |
|
a.getClass().getComponentType(), size); |
724 |
|
int i = 0; |
725 |
< |
Object[] result = a; |
725 |
> |
Object[] result = a; |
726 |
|
for (Entry<E> e = header.next; e != header; e = e.next) |
727 |
|
result[i++] = e.element; |
728 |
|
|
739 |
|
* is, serialize it). |
740 |
|
* |
741 |
|
* @serialData The size of the list (the number of elements it |
742 |
< |
* contains) is emitted (int), followed by all of its |
742 |
> |
* contains) is emitted (int), followed by all of its |
743 |
|
* elements (each an Object) in the proper order. |
744 |
|
*/ |
745 |
|
private void writeObject(java.io.ObjectOutputStream s) |
746 |
|
throws java.io.IOException { |
747 |
< |
// Write out any hidden serialization magic |
748 |
< |
s.defaultWriteObject(); |
747 |
> |
// Write out any hidden serialization magic |
748 |
> |
s.defaultWriteObject(); |
749 |
|
|
750 |
|
// Write out size |
751 |
|
s.writeInt(size); |
752 |
|
|
753 |
< |
// Write out all elements in the proper order. |
753 |
> |
// Write out all elements in the proper order. |
754 |
|
for (Entry e = header.next; e != header; e = e.next) |
755 |
|
s.writeObject(e.element); |
756 |
|
} |
761 |
|
*/ |
762 |
|
private void readObject(java.io.ObjectInputStream s) |
763 |
|
throws java.io.IOException, ClassNotFoundException { |
764 |
< |
// Read in any hidden serialization magic |
765 |
< |
s.defaultReadObject(); |
764 |
> |
// Read in any hidden serialization magic |
765 |
> |
s.defaultReadObject(); |
766 |
|
|
767 |
|
// Read in size |
768 |
|
int size = s.readInt(); |
771 |
|
header = new Entry<E>(null, null, null); |
772 |
|
header.next = header.previous = header; |
773 |
|
|
774 |
< |
// Read in all elements in the proper order. |
775 |
< |
for (int i=0; i<size; i++) |
774 |
> |
// Read in all elements in the proper order. |
775 |
> |
for (int i=0; i<size; i++) |
776 |
|
addBefore((E)s.readObject(), header); |
777 |
|
} |
778 |
|
} |