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Comparing jsr166/src/main/java/util/PriorityQueue.java (file contents):
Revision 1.63 by jsr166, Tue Mar 7 07:11:39 2006 UTC vs.
Revision 1.74 by jsr166, Wed Jul 13 11:27:28 2011 UTC

#	Line 1 | Line 1
1		/*
2	<	* %W% %E%
2	>	* Copyright (c) 2003, 2006, Oracle and/or its affiliates. All rights reserved.
3	>	* DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
4		*
5	<	* Copyright 2006 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.  Sun designates this
8	>	* particular file as subject to the "Classpath" exception as provided
9	>	* by Sun 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;
#	Line 52 | Line 70 | package java.util;
70		* ({@code peek}, {@code element}, and {@code size}).
71		*
72		* <p>This class is a member of the
73	<	* <a href="{@docRoot}/../guide/collections/index.html">
73	>	* <a href="{@docRoot}/../technotes/guides/collections/index.html">
74		* Java Collections Framework</a>.
75		*
76		* @since 1.5
59	–	* @version %I%, %G%
77		* @author Josh Bloch, Doug Lea
78		* @param <E> the type of elements held in this collection
79		*/
#	Line 153 | Line 170 | public class PriorityQueue<E> extends Ab
170		* @throws NullPointerException if the specified collection or any
171		*         of its elements are null
172		*/
173	+	@SuppressWarnings("unchecked")
174		public PriorityQueue(Collection<? extends E> c) {
175	<	initFromCollection(c);
176	<	if (c instanceof SortedSet)
177	<	comparator = (Comparator<? super E>)
178	<	((SortedSet<? extends E>)c).comparator();
179	<	else if (c instanceof PriorityQueue)
180	<	comparator = (Comparator<? super E>)
181	<	((PriorityQueue<? extends E>)c).comparator();
175	>	if (c instanceof SortedSet<?>) {
176	>	SortedSet<? extends E> ss = (SortedSet<? extends E>) c;
177	>	this.comparator = (Comparator<? super E>) ss.comparator();
178	>	initElementsFromCollection(ss);
179	>	}
180	>	else if (c instanceof PriorityQueue<?>) {
181	>	PriorityQueue<? extends E> pq = (PriorityQueue<? extends E>) c;
182	>	this.comparator = (Comparator<? super E>) pq.comparator();
183	>	initFromPriorityQueue(pq);
184	>	}
185		else {
186	<	comparator = null;
187	<	heapify();
186	>	this.comparator = null;
187	>	initFromCollection(c);
188		}
189		}
190
#	Line 181 | Line 202 | public class PriorityQueue<E> extends Ab
202		* @throws NullPointerException if the specified priority queue or any
203		*         of its elements are null
204		*/
205	+	@SuppressWarnings("unchecked")
206		public PriorityQueue(PriorityQueue<? extends E> c) {
207	<	comparator = (Comparator<? super E>)c.comparator();
208	<	initFromCollection(c);
207	>	this.comparator = (Comparator<? super E>) c.comparator();
208	>	initFromPriorityQueue(c);
209		}
210
211		/**
#	Line 199 | Line 221 | public class PriorityQueue<E> extends Ab
221		* @throws NullPointerException if the specified sorted set or any
222		*         of its elements are null
223		*/
224	+	@SuppressWarnings("unchecked")
225		public PriorityQueue(SortedSet<? extends E> c) {
226	<	comparator = (Comparator<? super E>)c.comparator();
227	<	initFromCollection(c);
226	>	this.comparator = (Comparator<? super E>) c.comparator();
227	>	initElementsFromCollection(c);
228	>	}
229	>
230	>	private void initFromPriorityQueue(PriorityQueue<? extends E> c) {
231	>	if (c.getClass() == PriorityQueue.class) {
232	>	this.queue = c.toArray();
233	>	this.size = c.size();
234	>	} else {
235	>	initFromCollection(c);
236	>	}
237	>	}
238	>
239	>	private void initElementsFromCollection(Collection<? extends E> c) {
240	>	Object[] a = c.toArray();
241	>	// If c.toArray incorrectly doesn't return Object[], copy it.
242	>	if (a.getClass() != Object[].class)
243	>	a = Arrays.copyOf(a, a.length, Object[].class);
244	>	int len = a.length;
245	>	if (len == 1 || this.comparator != null)
246	>	for (int i = 0; i < len; i++)
247	>	if (a[i] == null)
248	>	throw new NullPointerException();
249	>	this.queue = a;
250	>	this.size = a.length;
251		}
252
253		/**
#	Line 210 | Line 256 | public class PriorityQueue<E> extends Ab
256		* @param c the collection
257		*/
258		private void initFromCollection(Collection<? extends E> c) {
259	<	Object[] a = c.toArray();
260	<	// 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;
259	>	initElementsFromCollection(c);
260	>	heapify();
261		}
262
263		/**
264	+	* The maximum size of array to allocate.
265	+	* Some VMs reserve some header words in an array.
266	+	* Attempts to allocate larger arrays may result in
267	+	* OutOfMemoryError: Requested array size exceeds VM limit
268	+	*/
269	+	private static final int MAX_ARRAY_SIZE = Integer.MAX_VALUE - 8;
270	+
271	+	/**
272		* Increases the capacity of the array.
273		*
274		* @param minCapacity the desired minimum capacity
275		*/
276		private void grow(int minCapacity) {
277	<	if (minCapacity < 0) // overflow
228	<	throw new OutOfMemoryError();
229	<	int oldCapacity = queue.length;
277	>	int oldCapacity = queue.length;
278		// Double size if small; else grow by 50%
279	<	int newCapacity = ((oldCapacity < 64)?
280	<	((oldCapacity + 1) * 2):
281	<	((oldCapacity / 2) * 3));
282	<	if (newCapacity < 0) // overflow
283	<	newCapacity = Integer.MAX_VALUE;
284	<	if (newCapacity < minCapacity)
237	<	newCapacity = minCapacity;
279	>	int newCapacity = oldCapacity + ((oldCapacity < 64) ?
280	>	(oldCapacity + 2) :
281	>	(oldCapacity >> 1));
282	>	// overflow-conscious code
283	>	if (newCapacity - MAX_ARRAY_SIZE > 0)
284	>	newCapacity = hugeCapacity(minCapacity);
285		queue = Arrays.copyOf(queue, newCapacity);
286		}
287
288	+	private static int hugeCapacity(int minCapacity) {
289	+	if (minCapacity < 0) // overflow
290	+	throw new OutOfMemoryError();
291	+	return (minCapacity > MAX_ARRAY_SIZE) ?
292	+	Integer.MAX_VALUE :
293	+	MAX_ARRAY_SIZE;
294	+	}
295	+
296		/**
297		* Inserts the specified element into this priority queue.
298		*
#	Line 276 | Line 331 | public class PriorityQueue<E> extends Ab
331		}
332
333		public E peek() {
334	<	if (size == 0)
280	<	return null;
281	<	return (E) queue[0];
334	>	return (size == 0) ? null : (E) queue[0];
335		}
336
337		private int indexOf(Object o) {
338	<	if (o != null) {
338	>	if (o != null) {
339		for (int i = 0; i < size; i++)
340		if (o.equals(queue[i]))
341		return i;
#	Line 302 | Line 355 | public class PriorityQueue<E> extends Ab
355		* @return {@code true} if this queue changed as a result of the call
356		*/
357		public boolean remove(Object o) {
358	<	int i = indexOf(o);
359	<	if (i == -1)
360	<	return false;
361	<	else {
362	<	removeAt(i);
363	<	return true;
364	<	}
358	>	int i = indexOf(o);
359	>	if (i == -1)
360	>	return false;
361	>	else {
362	>	removeAt(i);
363	>	return true;
364	>	}
365		}
366
367		/**
#	Line 319 | Line 372 | public class PriorityQueue<E> extends Ab
372		* @return {@code true} if removed
373		*/
374		boolean removeEq(Object o) {
375	<	for (int i = 0; i < size; i++) {
376	<	if (o == queue[i]) {
375	>	for (int i = 0; i < size; i++) {
376	>	if (o == queue[i]) {
377		removeAt(i);
378		return true;
379		}
#	Line 337 | Line 390 | public class PriorityQueue<E> extends Ab
390		* @return {@code true} if this queue contains the specified element
391		*/
392		public boolean contains(Object o) {
393	<	return indexOf(o) != -1;
393	>	return indexOf(o) != -1;
394		}
395
396		/**
#	Line 379 | Line 432 | public class PriorityQueue<E> extends Ab
432		* The following code can be used to dump the queue into a newly
433		* allocated array of <tt>String</tt>:
434		*
435	<	* <pre>
383	<	*     String[] y = x.toArray(new String[0]);</pre>
435	>	*  <pre> {@code String[] y = x.toArray(new String[0]);}</pre>
436		*
437		* Note that <tt>toArray(new Object[0])</tt> is identical in function to
438		* <tt>toArray()</tt>.
#	Line 398 | Line 450 | public class PriorityQueue<E> extends Ab
450		if (a.length < size)
451		// Make a new array of a's runtime type, but my contents:
452		return (T[]) Arrays.copyOf(queue, size, a.getClass());
453	<	System.arraycopy(queue, 0, a, 0, size);
453	>	System.arraycopy(queue, 0, a, 0, size);
454		if (a.length > size)
455		a[size] = null;
456		return a;
#	Line 491 | Line 543 | public class PriorityQueue<E> extends Ab
543		lastRetElt = null;
544		} else {
545		throw new IllegalStateException();
546	<	}
546	>	}
547		expectedModCount = modCount;
548		}
549		}
#	Line 537 | Line 589 | public class PriorityQueue<E> extends Ab
589		* avoid missing traversing elements.
590		*/
591		private E removeAt(int i) {
592	<	assert i >= 0 && i < size;
592	>	// assert i >= 0 && i < size;
593		modCount++;
594		int s = --size;
595		if (s == i) // removed last element
#	Line 688 | Line 740 | public class PriorityQueue<E> extends Ab
740		// Write out array length, for compatibility with 1.5 version
741		s.writeInt(Math.max(2, size + 1));
742
743	<	// Write out all elements in the proper order.
743	>	// Write out all elements in the "proper order".
744		for (int i = 0; i < size; i++)
745		s.writeObject(queue[i]);
746		}
#	Line 707 | Line 759 | public class PriorityQueue<E> extends Ab
759		// Read in (and discard) array length
760		s.readInt();
761
762	<	queue = new Object[size];
762	>	queue = new Object[size];
763
764	<	// Read in all elements in the proper order.
764	>	// Read in all elements.
765		for (int i = 0; i < size; i++)
766		queue[i] = s.readObject();
767	+
768	+	// Elements are guaranteed to be in "proper order", but the
769	+	// spec has never explained what that might be.
770	+	heapify();
771		}
772		}

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