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Comparing jsr166/src/main/java/util/PriorityQueue.java (file contents):
Revision 1.66 by jsr166, Sun Jan 7 07:38:27 2007 UTC vs.
Revision 1.124 by jsr166, Sun May 6 19:35:51 2018 UTC

#	Line 1 | Line 1
1		/*
2	<	* %W% %E%
2	>	* Copyright (c) 2003, 2018, Oracle and/or its affiliates. All rights reserved.
3	>	* DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
4		*
5	<	* Copyright 2007 Sun Microsystems, Inc. All rights reserved.
6	<	* SUN PROPRIETARY/CONFIDENTIAL. Use is subject to license terms.
5	>	* This code is free software; you can redistribute it and/or modify it
6	>	* under the terms of the GNU General Public License version 2 only, as
7	>	* published by the Free Software Foundation.  Oracle designates this
8	>	* particular file as subject to the "Classpath" exception as provided
9	>	* by Oracle in the LICENSE file that accompanied this code.
10	>	*
11	>	* This code is distributed in the hope that it will be useful, but WITHOUT
12	>	* ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
13	>	* FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
14	>	* version 2 for more details (a copy is included in the LICENSE file that
15	>	* accompanied this code).
16	>	*
17	>	* You should have received a copy of the GNU General Public License version
18	>	* 2 along with this work; if not, write to the Free Software Foundation,
19	>	* Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
20	>	*
21	>	* Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
22	>	* or visit www.oracle.com if you need additional information or have any
23	>	* questions.
24		*/
25
26		package java.util;
27
28	+	import java.util.function.Consumer;
29	+	import jdk.internal.misc.SharedSecrets;
30	+
31		/**
32		* An unbounded priority {@linkplain Queue queue} based on a priority heap.
33		* The elements of the priority queue are ordered according to their
#	Line 34 | Line 55 | package java.util;
55		* <p>This class and its iterator implement all of the
56		* <em>optional</em> methods of the {@link Collection} and {@link
57		* Iterator} interfaces.  The Iterator provided in method {@link
58	<	* #iterator()} is <em>not</em> guaranteed to traverse the elements of
58	>	* #iterator()} and the Spliterator provided in method {@link #spliterator()}
59	>	* are <em>not</em> guaranteed to traverse the elements of
60		* the priority queue in any particular order. If you need ordered
61		* traversal, consider using {@code Arrays.sort(pq.toArray())}.
62		*
63	<	* <p> <strong>Note that this implementation is not synchronized.</strong>
63	>	* <p><strong>Note that this implementation is not synchronized.</strong>
64		* Multiple threads should not access a {@code PriorityQueue}
65		* instance concurrently if any of the threads modifies the queue.
66		* Instead, use the thread-safe {@link
67		* java.util.concurrent.PriorityBlockingQueue} class.
68		*
69		* <p>Implementation note: this implementation provides
70	<	* O(log(n)) time for the enqueing and dequeing methods
70	>	* O(log(n)) time for the enqueuing and dequeuing methods
71		* ({@code offer}, {@code poll}, {@code remove()} and {@code add});
72		* linear time for the {@code remove(Object)} and {@code contains(Object)}
73		* methods; and constant time for the retrieval methods
74		* ({@code peek}, {@code element}, and {@code size}).
75		*
76		* <p>This class is a member of the
77	<	* <a href="{@docRoot}/../technotes/guides/collections/index.html">
77	>	* <a href="{@docRoot}/java/util/package-summary.html#CollectionsFramework">
78		* Java Collections Framework</a>.
79		*
80		* @since 1.5
59	–	* @version %I%, %G%
81		* @author Josh Bloch, Doug Lea
82	<	* @param <E> the type of elements held in this collection
82	>	* @param <E> the type of elements held in this queue
83		*/
84	+	@SuppressWarnings("unchecked")
85		public class PriorityQueue<E> extends AbstractQueue<E>
86		implements java.io.Serializable {
87
#	Line 75 | Line 97 | public class PriorityQueue<E> extends Ab
97		* heap and each descendant d of n, n <= d.  The element with the
98		* lowest value is in queue[0], assuming the queue is nonempty.
99		*/
100	<	private transient Object[] queue;
100	>	transient Object[] queue; // non-private to simplify nested class access
101
102		/**
103		* The number of elements in the priority queue.
104		*/
105	<	private int size = 0;
105	>	int size;
106
107		/**
108		* The comparator, or null if priority queue uses elements'
#	Line 92 | Line 114 | public class PriorityQueue<E> extends Ab
114		* The number of times this priority queue has been
115		* <i>structurally modified</i>.  See AbstractList for gory details.
116		*/
117	<	private transient int modCount = 0;
117	>	transient int modCount;     // non-private to simplify nested class access
118
119		/**
120		* Creates a {@code PriorityQueue} with the default initial
#	Line 117 | Line 139 | public class PriorityQueue<E> extends Ab
139		}
140
141		/**
142	+	* Creates a {@code PriorityQueue} with the default initial capacity and
143	+	* whose elements are ordered according to the specified comparator.
144	+	*
145	+	* @param  comparator the comparator that will be used to order this
146	+	*         priority queue.  If {@code null}, the {@linkplain Comparable
147	+	*         natural ordering} of the elements will be used.
148	+	* @since 1.8
149	+	*/
150	+	public PriorityQueue(Comparator<? super E> comparator) {
151	+	this(DEFAULT_INITIAL_CAPACITY, comparator);
152	+	}
153	+
154	+	/**
155		* Creates a {@code PriorityQueue} with the specified initial capacity
156		* that orders its elements according to the specified comparator.
157		*
#	Line 154 | Line 189 | public class PriorityQueue<E> extends Ab
189		*         of its elements are null
190		*/
191		public PriorityQueue(Collection<? extends E> c) {
192	<	initFromCollection(c);
193	<	if (c instanceof SortedSet)
194	<	comparator = (Comparator<? super E>)
195	<	((SortedSet<? extends E>)c).comparator();
196	<	else if (c instanceof PriorityQueue)
197	<	comparator = (Comparator<? super E>)
198	<	((PriorityQueue<? extends E>)c).comparator();
192	>	if (c instanceof SortedSet<?>) {
193	>	SortedSet<? extends E> ss = (SortedSet<? extends E>) c;
194	>	this.comparator = (Comparator<? super E>) ss.comparator();
195	>	initElementsFromCollection(ss);
196	>	}
197	>	else if (c instanceof PriorityQueue<?>) {
198	>	PriorityQueue<? extends E> pq = (PriorityQueue<? extends E>) c;
199	>	this.comparator = (Comparator<? super E>) pq.comparator();
200	>	initFromPriorityQueue(pq);
201	>	}
202		else {
203	<	comparator = null;
204	<	heapify();
203	>	this.comparator = null;
204	>	initFromCollection(c);
205		}
206		}
207
#	Line 182 | Line 220 | public class PriorityQueue<E> extends Ab
220		*         of its elements are null
221		*/
222		public PriorityQueue(PriorityQueue<? extends E> c) {
223	<	comparator = (Comparator<? super E>)c.comparator();
224	<	initFromCollection(c);
223	>	this.comparator = (Comparator<? super E>) c.comparator();
224	>	initFromPriorityQueue(c);
225		}
226
227		/**
#	Line 200 | Line 238 | public class PriorityQueue<E> extends Ab
238		*         of its elements are null
239		*/
240		public PriorityQueue(SortedSet<? extends E> c) {
241	<	comparator = (Comparator<? super E>)c.comparator();
242	<	initFromCollection(c);
241	>	this.comparator = (Comparator<? super E>) c.comparator();
242	>	initElementsFromCollection(c);
243	>	}
244	>
245	>	private void initFromPriorityQueue(PriorityQueue<? extends E> c) {
246	>	if (c.getClass() == PriorityQueue.class) {
247	>	this.queue = c.toArray();
248	>	this.size = c.size();
249	>	} else {
250	>	initFromCollection(c);
251	>	}
252	>	}
253	>
254	>	private void initElementsFromCollection(Collection<? extends E> c) {
255	>	Object[] es = c.toArray();
256	>	int len = es.length;
257	>	// If c.toArray incorrectly doesn't return Object[], copy it.
258	>	if (es.getClass() != Object[].class)
259	>	es = Arrays.copyOf(es, len, Object[].class);
260	>	if (len == 1 || this.comparator != null)
261	>	for (Object e : es)
262	>	if (e == null)
263	>	throw new NullPointerException();
264	>	this.queue = es;
265	>	this.size = len;
266		}
267
268		/**
#	Line 210 | Line 271 | public class PriorityQueue<E> extends Ab
271		* @param c the collection
272		*/
273		private void initFromCollection(Collection<? extends E> c) {
274	<	Object[] a = c.toArray();
275	<	// If c.toArray incorrectly doesn't return Object[], copy it.
215	<	if (a.getClass() != Object[].class)
216	<	a = Arrays.copyOf(a, a.length, Object[].class);
217	<	queue = a;
218	<	size = a.length;
274	>	initElementsFromCollection(c);
275	>	heapify();
276		}
277
278		/**
279	+	* The maximum size of array to allocate.
280	+	* Some VMs reserve some header words in an array.
281	+	* Attempts to allocate larger arrays may result in
282	+	* OutOfMemoryError: Requested array size exceeds VM limit
283	+	*/
284	+	private static final int MAX_ARRAY_SIZE = Integer.MAX_VALUE - 8;
285	+
286	+	/**
287		* Increases the capacity of the array.
288		*
289		* @param minCapacity the desired minimum capacity
290		*/
291		private void grow(int minCapacity) {
292	<	if (minCapacity < 0) // overflow
228	<	throw new OutOfMemoryError();
229	<	int oldCapacity = queue.length;
292	>	int oldCapacity = queue.length;
293		// Double size if small; else grow by 50%
294	<	int newCapacity = ((oldCapacity < 64)?
295	<	((oldCapacity + 1) * 2):
296	<	((oldCapacity / 2) * 3));
297	<	if (newCapacity < 0) // overflow
298	<	newCapacity = Integer.MAX_VALUE;
299	<	if (newCapacity < minCapacity)
237	<	newCapacity = minCapacity;
294	>	int newCapacity = oldCapacity + ((oldCapacity < 64) ?
295	>	(oldCapacity + 2) :
296	>	(oldCapacity >> 1));
297	>	// overflow-conscious code
298	>	if (newCapacity - MAX_ARRAY_SIZE > 0)
299	>	newCapacity = hugeCapacity(minCapacity);
300		queue = Arrays.copyOf(queue, newCapacity);
301		}
302
303	+	private static int hugeCapacity(int minCapacity) {
304	+	if (minCapacity < 0) // overflow
305	+	throw new OutOfMemoryError();
306	+	return (minCapacity > MAX_ARRAY_SIZE) ?
307	+	Integer.MAX_VALUE :
308	+	MAX_ARRAY_SIZE;
309	+	}
310	+
311		/**
312		* Inserts the specified element into this priority queue.
313		*
#	Line 267 | Line 337 | public class PriorityQueue<E> extends Ab
337		int i = size;
338		if (i >= queue.length)
339		grow(i + 1);
340	+	siftUp(i, e);
341		size = i + 1;
271	–	if (i == 0)
272	–	queue[0] = e;
273	–	else
274	–	siftUp(i, e);
342		return true;
343		}
344
345		public E peek() {
346	<	if (size == 0)
280	<	return null;
281	<	return (E) queue[0];
346	>	return (size == 0) ? null : (E) queue[0];
347		}
348
349		private int indexOf(Object o) {
350	<	if (o != null) {
351	<	for (int i = 0; i < size; i++)
352	<	if (o.equals(queue[i]))
350	>	if (o != null) {
351	>	final Object[] es = queue;
352	>	for (int i = 0, n = size; i < n; i++)
353	>	if (o.equals(es[i]))
354		return i;
355		}
356		return -1;
#	Line 302 | Line 368 | public class PriorityQueue<E> extends Ab
368		* @return {@code true} if this queue changed as a result of the call
369		*/
370		public boolean remove(Object o) {
371	<	int i = indexOf(o);
372	<	if (i == -1)
373	<	return false;
374	<	else {
375	<	removeAt(i);
376	<	return true;
377	<	}
371	>	int i = indexOf(o);
372	>	if (i == -1)
373	>	return false;
374	>	else {
375	>	removeAt(i);
376	>	return true;
377	>	}
378		}
379
380		/**
381	<	* Version of remove using reference equality, not equals.
316	<	* Needed by iterator.remove.
381	>	* Identity-based version for use in Itr.remove.
382		*
383		* @param o element to be removed from this queue, if present
319	–	* @return {@code true} if removed
384		*/
385	<	boolean removeEq(Object o) {
386	<	for (int i = 0; i < size; i++) {
387	<	if (o == queue[i]) {
385	>	void removeEq(Object o) {
386	>	final Object[] es = queue;
387	>	for (int i = 0, n = size; i < n; i++) {
388	>	if (o == es[i]) {
389		removeAt(i);
390	<	return true;
390	>	break;
391		}
392		}
328	–	return false;
393		}
394
395		/**
#	Line 337 | Line 401 | public class PriorityQueue<E> extends Ab
401		* @return {@code true} if this queue contains the specified element
402		*/
403		public boolean contains(Object o) {
404	<	return indexOf(o) != -1;
404	>	return indexOf(o) >= 0;
405		}
406
407		/**
#	Line 375 | Line 439 | public class PriorityQueue<E> extends Ab
439		* precise control over the runtime type of the output array, and may,
440		* under certain circumstances, be used to save allocation costs.
441		*
442	<	* <p>Suppose <tt>x</tt> is a queue known to contain only strings.
442	>	* <p>Suppose {@code x} is a queue known to contain only strings.
443		* The following code can be used to dump the queue into a newly
444	<	* allocated array of <tt>String</tt>:
444	>	* allocated array of {@code String}:
445		*
446	<	* <pre>
383	<	*     String[] y = x.toArray(new String[0]);</pre>
446	>	* <pre> {@code String[] y = x.toArray(new String[0]);}</pre>
447		*
448	<	* Note that <tt>toArray(new Object[0])</tt> is identical in function to
449	<	* <tt>toArray()</tt>.
448	>	* Note that {@code toArray(new Object[0])} is identical in function to
449	>	* {@code toArray()}.
450		*
451		* @param a the array into which the elements of the queue are to
452		*          be stored, if it is big enough; otherwise, a new array of the
#	Line 395 | Line 458 | public class PriorityQueue<E> extends Ab
458		* @throws NullPointerException if the specified array is null
459		*/
460		public <T> T[] toArray(T[] a) {
461	+	final int size = this.size;
462		if (a.length < size)
463		// Make a new array of a's runtime type, but my contents:
464		return (T[]) Arrays.copyOf(queue, size, a.getClass());
465	<	System.arraycopy(queue, 0, a, 0, size);
465	>	System.arraycopy(queue, 0, a, 0, size);
466		if (a.length > size)
467		a[size] = null;
468		return a;
#	Line 419 | Line 483 | public class PriorityQueue<E> extends Ab
483		* Index (into queue array) of element to be returned by
484		* subsequent call to next.
485		*/
486	<	private int cursor = 0;
486	>	private int cursor;
487
488		/**
489		* Index of element returned by most recent call to next,
#	Line 439 | Line 503 | public class PriorityQueue<E> extends Ab
503		* We expect that most iterations, even those involving removals,
504		* will not need to store elements in this field.
505		*/
506	<	private ArrayDeque<E> forgetMeNot = null;
506	>	private ArrayDeque<E> forgetMeNot;
507
508		/**
509		* Element returned by the most recent call to next iff that
510		* element was drawn from the forgetMeNot list.
511		*/
512	<	private E lastRetElt = null;
512	>	private E lastRetElt;
513
514		/**
515		* The modCount value that the iterator believes that the backing
#	Line 454 | Line 518 | public class PriorityQueue<E> extends Ab
518		*/
519		private int expectedModCount = modCount;
520
521	+	Itr() {}                        // prevent access constructor creation
522	+
523		public boolean hasNext() {
524		return cursor < size ||
525		(forgetMeNot != null && !forgetMeNot.isEmpty());
#	Line 483 | Line 549 | public class PriorityQueue<E> extends Ab
549		cursor--;
550		else {
551		if (forgetMeNot == null)
552	<	forgetMeNot = new ArrayDeque<E>();
552	>	forgetMeNot = new ArrayDeque<>();
553		forgetMeNot.add(moved);
554		}
555		} else if (lastRetElt != null) {
#	Line 491 | Line 557 | public class PriorityQueue<E> extends Ab
557		lastRetElt = null;
558		} else {
559		throw new IllegalStateException();
560	<	}
560	>	}
561		expectedModCount = modCount;
562		}
563		}
#	Line 506 | Line 572 | public class PriorityQueue<E> extends Ab
572		*/
573		public void clear() {
574		modCount++;
575	<	for (int i = 0; i < size; i++)
576	<	queue[i] = null;
575	>	final Object[] es = queue;
576	>	for (int i = 0, n = size; i < n; i++)
577	>	es[i] = null;
578		size = 0;
579		}
580
#	Line 536 | Line 603 | public class PriorityQueue<E> extends Ab
603		* position before i. This fact is used by iterator.remove so as to
604		* avoid missing traversing elements.
605		*/
606	<	private E removeAt(int i) {
607	<	assert i >= 0 && i < size;
606	>	E removeAt(int i) {
607	>	// assert i >= 0 && i < size;
608		modCount++;
609		int s = --size;
610		if (s == i) // removed last element
#	Line 560 | Line 627 | public class PriorityQueue<E> extends Ab
627		* promoting x up the tree until it is greater than or equal to
628		* its parent, or is the root.
629		*
630	<	* To simplify and speed up coercions and comparisons. the
630	>	* To simplify and speed up coercions and comparisons, the
631		* Comparable and Comparator versions are separated into different
632		* methods that are otherwise identical. (Similarly for siftDown.)
633		*
#	Line 569 | Line 636 | public class PriorityQueue<E> extends Ab
636		*/
637		private void siftUp(int k, E x) {
638		if (comparator != null)
639	<	siftUpUsingComparator(k, x);
639	>	siftUpUsingComparator(k, x, queue, comparator);
640		else
641	<	siftUpComparable(k, x);
641	>	siftUpComparable(k, x, queue);
642		}
643
644	<	private void siftUpComparable(int k, E x) {
645	<	Comparable<? super E> key = (Comparable<? super E>) x;
644	>	private static <T> void siftUpComparable(int k, T x, Object[] es) {
645	>	Comparable<? super T> key = (Comparable<? super T>) x;
646		while (k > 0) {
647		int parent = (k - 1) >>> 1;
648	<	Object e = queue[parent];
649	<	if (key.compareTo((E) e) >= 0)
648	>	Object e = es[parent];
649	>	if (key.compareTo((T) e) >= 0)
650		break;
651	<	queue[k] = e;
651	>	es[k] = e;
652		k = parent;
653		}
654	<	queue[k] = key;
654	>	es[k] = key;
655		}
656
657	<	private void siftUpUsingComparator(int k, E x) {
657	>	private static <T> void siftUpUsingComparator(
658	>	int k, T x, Object[] es, Comparator<? super T> cmp) {
659		while (k > 0) {
660		int parent = (k - 1) >>> 1;
661	<	Object e = queue[parent];
662	<	if (comparator.compare(x, (E) e) >= 0)
661	>	Object e = es[parent];
662	>	if (cmp.compare(x, (T) e) >= 0)
663		break;
664	<	queue[k] = e;
664	>	es[k] = e;
665		k = parent;
666		}
667	<	queue[k] = x;
667	>	es[k] = x;
668		}
669
670		/**
#	Line 609 | Line 677 | public class PriorityQueue<E> extends Ab
677		*/
678		private void siftDown(int k, E x) {
679		if (comparator != null)
680	<	siftDownUsingComparator(k, x);
680	>	siftDownUsingComparator(k, x, queue, size, comparator);
681		else
682	<	siftDownComparable(k, x);
682	>	siftDownComparable(k, x, queue, size);
683		}
684
685	<	private void siftDownComparable(int k, E x) {
686	<	Comparable<? super E> key = (Comparable<? super E>)x;
687	<	int half = size >>> 1;        // loop while a non-leaf
685	>	private static <T> void siftDownComparable(int k, T x, Object[] es, int n) {
686	>	// assert n > 0;
687	>	Comparable<? super T> key = (Comparable<? super T>)x;
688	>	int half = n >>> 1;           // loop while a non-leaf
689		while (k < half) {
690		int child = (k << 1) + 1; // assume left child is least
691	<	Object c = queue[child];
691	>	Object c = es[child];
692		int right = child + 1;
693	<	if (right < size &&
694	<	((Comparable<? super E>) c).compareTo((E) queue[right]) > 0)
695	<	c = queue[child = right];
696	<	if (key.compareTo((E) c) <= 0)
693	>	if (right < n &&
694	>	((Comparable<? super T>) c).compareTo((T) es[right]) > 0)
695	>	c = es[child = right];
696	>	if (key.compareTo((T) c) <= 0)
697		break;
698	<	queue[k] = c;
698	>	es[k] = c;
699		k = child;
700		}
701	<	queue[k] = key;
701	>	es[k] = key;
702		}
703
704	<	private void siftDownUsingComparator(int k, E x) {
705	<	int half = size >>> 1;
704	>	private static <T> void siftDownUsingComparator(
705	>	int k, T x, Object[] es, int n, Comparator<? super T> cmp) {
706	>	// assert n > 0;
707	>	int half = n >>> 1;
708		while (k < half) {
709		int child = (k << 1) + 1;
710	<	Object c = queue[child];
710	>	Object c = es[child];
711		int right = child + 1;
712	<	if (right < size &&
713	<	comparator.compare((E) c, (E) queue[right]) > 0)
714	<	c = queue[child = right];
644	<	if (comparator.compare(x, (E) c) <= 0)
712	>	if (right < n && cmp.compare((T) c, (T) es[right]) > 0)
713	>	c = es[child = right];
714	>	if (cmp.compare(x, (T) c) <= 0)
715		break;
716	<	queue[k] = c;
716	>	es[k] = c;
717		k = child;
718		}
719	<	queue[k] = x;
719	>	es[k] = x;
720		}
721
722		/**
723		* Establishes the heap invariant (described above) in the entire tree,
724		* assuming nothing about the order of the elements prior to the call.
725	+	* This classic algorithm due to Floyd (1964) is known to be O(size).
726		*/
727		private void heapify() {
728	<	for (int i = (size >>> 1) - 1; i >= 0; i--)
729	<	siftDown(i, (E) queue[i]);
728	>	final Object[] es = queue;
729	>	int n = size, i = (n >>> 1) - 1;
730	>	Comparator<? super E> cmp = comparator;
731	>	if (cmp == null)
732	>	for (; i >= 0; i--)
733	>	siftDownComparable(i, (E) es[i], es, n);
734	>	else
735	>	for (; i >= 0; i--)
736	>	siftDownUsingComparator(i, (E) es[i], es, n, cmp);
737		}
738
739		/**
#	Line 672 | Line 750 | public class PriorityQueue<E> extends Ab
750		}
751
752		/**
753	<	* Saves the state of the instance to a stream (that
676	<	* is, serializes it).
753	>	* Saves this queue to a stream (that is, serializes it).
754		*
755	+	* @param s the stream
756	+	* @throws java.io.IOException if an I/O error occurs
757		* @serialData The length of the array backing the instance is
758		*             emitted (int), followed by all of its elements
759		*             (each an {@code Object}) in the proper order.
681	–	* @param s the stream
760		*/
761		private void writeObject(java.io.ObjectOutputStream s)
762	<	throws java.io.IOException{
762	>	throws java.io.IOException {
763		// Write out element count, and any hidden stuff
764		s.defaultWriteObject();
765
#	Line 689 | Line 767 | public class PriorityQueue<E> extends Ab
767		s.writeInt(Math.max(2, size + 1));
768
769		// Write out all elements in the "proper order".
770	<	for (int i = 0; i < size; i++)
771	<	s.writeObject(queue[i]);
770	>	final Object[] es = queue;
771	>	for (int i = 0, n = size; i < n; i++)
772	>	s.writeObject(es[i]);
773		}
774
775		/**
#	Line 698 | Line 777 | public class PriorityQueue<E> extends Ab
777		* (that is, deserializes it).
778		*
779		* @param s the stream
780	+	* @throws ClassNotFoundException if the class of a serialized object
781	+	*         could not be found
782	+	* @throws java.io.IOException if an I/O error occurs
783		*/
784		private void readObject(java.io.ObjectInputStream s)
785		throws java.io.IOException, ClassNotFoundException {
#	Line 707 | Line 789 | public class PriorityQueue<E> extends Ab
789		// Read in (and discard) array length
790		s.readInt();
791
792	<	queue = new Object[size];
792	>	SharedSecrets.getJavaObjectInputStreamAccess().checkArray(s, Object[].class, size);
793	>	queue = new Object[size];
794
795		// Read in all elements.
796	<	for (int i = 0; i < size; i++)
797	<	queue[i] = s.readObject();
796	>	final Object[] es = queue;
797	>	for (int i = 0, n = size; i < n; i++)
798	>	es[i] = s.readObject();
799	>
800	>	// Elements are guaranteed to be in "proper order", but the
801	>	// spec has never explained what that might be.
802	>	heapify();
803	>	}
804	>
805	>	/**
806	>	* Creates a <em><a href="Spliterator.html#binding">late-binding</a></em>
807	>	* and <em>fail-fast</em> {@link Spliterator} over the elements in this
808	>	* queue. The spliterator does not traverse elements in any particular order
809	>	* (the {@link Spliterator#ORDERED ORDERED} characteristic is not reported).
810	>	*
811	>	* <p>The {@code Spliterator} reports {@link Spliterator#SIZED},
812	>	* {@link Spliterator#SUBSIZED}, and {@link Spliterator#NONNULL}.
813	>	* Overriding implementations should document the reporting of additional
814	>	* characteristic values.
815	>	*
816	>	* @return a {@code Spliterator} over the elements in this queue
817	>	* @since 1.8
818	>	*/
819	>	public final Spliterator<E> spliterator() {
820	>	return new PriorityQueueSpliterator(0, -1, 0);
821	>	}
822
823	<	// Elements are guaranteed to be in "proper order", but the
824	<	// spec has never explained what that might be.
825	<	heapify();
823	>	final class PriorityQueueSpliterator implements Spliterator<E> {
824	>	private int index;            // current index, modified on advance/split
825	>	private int fence;            // -1 until first use
826	>	private int expectedModCount; // initialized when fence set
827	>
828	>	/** Creates new spliterator covering the given range. */
829	>	PriorityQueueSpliterator(int origin, int fence, int expectedModCount) {
830	>	this.index = origin;
831	>	this.fence = fence;
832	>	this.expectedModCount = expectedModCount;
833	>	}
834	>
835	>	private int getFence() { // initialize fence to size on first use
836	>	int hi;
837	>	if ((hi = fence) < 0) {
838	>	expectedModCount = modCount;
839	>	hi = fence = size;
840	>	}
841	>	return hi;
842	>	}
843	>
844	>	public PriorityQueueSpliterator trySplit() {
845	>	int hi = getFence(), lo = index, mid = (lo + hi) >>> 1;
846	>	return (lo >= mid) ? null :
847	>	new PriorityQueueSpliterator(lo, index = mid, expectedModCount);
848	>	}
849	>
850	>	public void forEachRemaining(Consumer<? super E> action) {
851	>	if (action == null)
852	>	throw new NullPointerException();
853	>	if (fence < 0) { fence = size; expectedModCount = modCount; }
854	>	final Object[] es = queue;
855	>	int i, hi; E e;
856	>	for (i = index, index = hi = fence; i < hi; i++) {
857	>	if ((e = (E) es[i]) == null)
858	>	break;      // must be CME
859	>	action.accept(e);
860	>	}
861	>	if (modCount != expectedModCount)
862	>	throw new ConcurrentModificationException();
863	>	}
864	>
865	>	public boolean tryAdvance(Consumer<? super E> action) {
866	>	if (action == null)
867	>	throw new NullPointerException();
868	>	if (fence < 0) { fence = size; expectedModCount = modCount; }
869	>	int i;
870	>	if ((i = index) < fence) {
871	>	index = i + 1;
872	>	E e;
873	>	if ((e = (E) queue[i]) == null
874	>	|| modCount != expectedModCount)
875	>	throw new ConcurrentModificationException();
876	>	action.accept(e);
877	>	return true;
878	>	}
879	>	return false;
880	>	}
881	>
882	>	public long estimateSize() {
883	>	return getFence() - index;
884	>	}
885	>
886	>	public int characteristics() {
887	>	return Spliterator.SIZED | Spliterator.SUBSIZED | Spliterator.NONNULL;
888	>	}
889	>	}
890	>
891	>	/**
892	>	* @throws NullPointerException {@inheritDoc}
893	>	*/
894	>	public void forEach(Consumer<? super E> action) {
895	>	Objects.requireNonNull(action);
896	>	final int expectedModCount = modCount;
897	>	final Object[] es = queue;
898	>	for (int i = 0, n = size; i < n; i++)
899	>	action.accept((E) es[i]);
900	>	if (expectedModCount != modCount)
901	>	throw new ConcurrentModificationException();
902		}
903		}

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