ViewVC Help

View File | Revision Log | Show Annotations | Download File | Root Listing

root/jsr166/jsr166/src/main/java/util/PriorityQueue.java

Comparing jsr166/src/main/java/util/PriorityQueue.java (file contents):
Revision 1.54 by jsr166, Thu Nov 24 03:44:57 2005 UTC vs.
Revision 1.55 by dl, Sun Nov 27 20:41:02 2005 UTC

#	Line 68 | Line 68 | public class PriorityQueue<E> extends Ab
68		private static final int DEFAULT_INITIAL_CAPACITY = 11;
69
70		/**
71	<	* Priority queue represented as a balanced binary heap: the two children
72	<	* of queue[n] are queue[2*n] and queue[2*n + 1].  The priority queue is
73	<	* ordered by comparator, or by the elements' natural ordering, if
74	<	* comparator is null:  For each node n in the heap and each descendant d
75	<	* of n, n <= d.
76	<	*
77	<	* The element with the lowest value is in queue[1], assuming the queue is
78	<	* nonempty.  (A one-based array is used in preference to the traditional
79	<	* zero-based array to simplify parent and child calculations.)
80	<	*
81	<	* queue.length must be >= 2, even if size == 0.
71	>	* Priority queue represented as a balanced binary heap: the two
72	>	* children of queue[n] are queue[2*n+1] and queue[2*(n+1)].  The
73	>	* priority queue is ordered by comparator, or by the elements'
74	>	* natural ordering, if comparator is null: For each node n in the
75	>	* heap and each descendant d of n, n <= d.  The element with the
76	>	* lowest value is in queue[0], assuming the queue is nonempty.
77		*/
78		private transient Object[] queue;
79
#	Line 134 | Line 129 | public class PriorityQueue<E> extends Ab
129		*/
130		public PriorityQueue(int initialCapacity,
131		Comparator<? super E> comparator) {
132	+	// Note: This restriction of at least one is not actually needed,
133	+	// but continues for 1.5 compatibility
134		if (initialCapacity < 1)
135		throw new IllegalArgumentException();
136	<	this.queue = new Object[initialCapacity + 1];
136	>	this.queue = new Object[initialCapacity];
137		this.comparator = comparator;
138		}
139	<
143	<	/**
144	<	* Common code to initialize underlying queue array across
145	<	* constructors below.
146	<	*/
147	<	private void initializeArray(Collection<? extends E> c) {
148	<	int sz = c.size();
149	<	int initialCapacity = (int)Math.min((sz * 110L) / 100,
150	<	Integer.MAX_VALUE - 1);
151	<	if (initialCapacity < 1)
152	<	initialCapacity = 1;
153	<
154	<	this.queue = new Object[initialCapacity + 1];
155	<	}
156	<
157	<	/**
158	<	* Initially fill elements of the queue array under the
159	<	* knowledge that it is sorted or is another PQ, in which
160	<	* case we can just place the elements in the order presented.
161	<	*/
162	<	private void fillFromSorted(Collection<? extends E> c) {
163	<	for (Iterator<? extends E> i = c.iterator(); i.hasNext(); ) {
164	<	int k = ++size;
165	<	if (k >= queue.length)
166	<	grow(k);
167	<	queue[k] = i.next();
168	<	}
169	<	}
170	<
171	<	/**
172	<	* Initially fill elements of the queue array that is not to our knowledge
173	<	* sorted, so we must rearrange the elements to guarantee the heap
174	<	* invariant.
175	<	*/
176	<	private void fillFromUnsorted(Collection<? extends E> c) {
177	<	for (Iterator<? extends E> i = c.iterator(); i.hasNext(); ) {
178	<	int k = ++size;
179	<	if (k >= queue.length)
180	<	grow(k);
181	<	queue[k] = i.next();
182	<	}
183	<	heapify();
184	<	}
185	<
139	>
140		/**
141		* Creates a <tt>PriorityQueue</tt> containing the elements in the
142	<	* specified collection.  The priority queue has an initial
189	<	* capacity of 110% of the size of the specified collection or 1
190	<	* if the collection is empty.  If the specified collection is an
142	>	* specified collection.   If the specified collection is an
143		* instance of a {@link java.util.SortedSet} or is another
144		* <tt>PriorityQueue</tt>, the priority queue will be ordered
145		* according to the same ordering.  Otherwise, this priority queue
#	Line 202 | Line 154 | public class PriorityQueue<E> extends Ab
154		*         of its elements are null
155		*/
156		public PriorityQueue(Collection<? extends E> c) {
157	<	initializeArray(c);
158	<	if (c instanceof SortedSet) {
159	<	SortedSet<? extends E> s = (SortedSet<? extends E>)c;
160	<	comparator = (Comparator<? super E>)s.comparator();
161	<	fillFromSorted(s);
162	<	} else if (c instanceof PriorityQueue) {
163	<	PriorityQueue<? extends E> s = (PriorityQueue<? extends E>) c;
164	<	comparator = (Comparator<? super E>)s.comparator();
213	<	fillFromSorted(s);
214	<	} else {
157	>	initFromCollection(c);
158	>	if (c instanceof SortedSet)
159	>	comparator = (Comparator<? super E>)
160	>	((SortedSet<? extends E>)c).comparator();
161	>	else if (c instanceof PriorityQueue)
162	>	comparator = (Comparator<? super E>)
163	>	((PriorityQueue<? extends E>)c).comparator();
164	>	else {
165		comparator = null;
166	<	fillFromUnsorted(c);
166	>	heapify();
167		}
168		}
169
170		/**
171		* Creates a <tt>PriorityQueue</tt> containing the elements in the
172	<	* specified priority queue.  The priority queue has an initial
223	<	* capacity of 110% of the size of the specified priority queue or
224	<	* 1 if the priority queue is empty.  This priority queue will be
172	>	* specified priority queue.  This priority queue will be
173		* ordered according to the same ordering as the given priority
174		* queue.
175		*
#	Line 234 | Line 182 | public class PriorityQueue<E> extends Ab
182		*         of its elements are null
183		*/
184		public PriorityQueue(PriorityQueue<? extends E> c) {
237	–	initializeArray(c);
185		comparator = (Comparator<? super E>)c.comparator();
186	<	fillFromSorted(c);
186	>	initFromCollection(c);
187		}
188
189		/**
190		* Creates a <tt>PriorityQueue</tt> containing the elements in the
191	<	* specified sorted set.  The priority queue has an initial
245	<	* capacity of 110% of the size of the specified sorted set or 1
246	<	* if the sorted set is empty.  This priority queue will be ordered
191	>	* specified sorted set.  This priority queue will be ordered
192		* according to the same ordering as the given sorted set.
193		*
194		* @param  c the sorted set whose elements are to be placed
#	Line 255 | Line 200 | public class PriorityQueue<E> extends Ab
200		*         of its elements are null
201		*/
202		public PriorityQueue(SortedSet<? extends E> c) {
258	–	initializeArray(c);
203		comparator = (Comparator<? super E>)c.comparator();
204	<	fillFromSorted(c);
204	>	initFromCollection(c);
205		}
206
207		/**
208	<	* Resize array, if necessary, to be able to hold given index.
208	>	* Initialize queue array with elements from the given Collection.
209	>	* @param c the collection
210		*/
211	<	private void grow(int index) {
212	<	int newlen = queue.length;
213	<	if (index < newlen) // don't need to grow
214	<	return;
215	<	if (index == Integer.MAX_VALUE)
211	>	private void initFromCollection(Collection<? extends E> c) {
212	>	Object[] a = c.toArray();
213	>	// If c.toArray incorrectly doesn't return Object[], copy it.
214	>	if (a.getClass() != Object[].class)
215	>	a = Arrays.copyOf(a, a.length, Object[].class);
216	>	queue = a;
217	>	size = a.length;
218	>	}
219	>
220	>	/**
221	>	* Increases the capacity of the array.
222	>	*
223	>	* @param minCapacity the desired minimum capacity
224	>	*/
225	>	private void grow(int minCapacity) {
226	>	if (minCapacity < 0) // overflow
227		throw new OutOfMemoryError();
228	<	while (newlen <= index) {
229	<	if (newlen >= Integer.MAX_VALUE / 2)  // avoid overflow
230	<	newlen = Integer.MAX_VALUE;
231	<	else
232	<	newlen <<= 1;
233	<	}
234	<	queue = Arrays.copyOf(queue, newlen);
228	>	int oldCapacity = queue.length;
229	>	// Double size if small; else grow by 50%
230	>	int newCapacity = ((oldCapacity < 64)?
231	>	((oldCapacity + 1) * 2):
232	>	((oldCapacity * 3) / 2));
233	>	if (newCapacity < minCapacity)
234	>	newCapacity = minCapacity;
235	>	queue = Arrays.copyOf(queue, newCapacity);
236		}
237
238		/**
#	Line 304 | Line 261 | public class PriorityQueue<E> extends Ab
261		if (e == null)
262		throw new NullPointerException();
263		modCount++;
264	<	++size;
265	<
266	<	// Grow backing store if necessary
267	<	if (size >= queue.length)
268	<	grow(size);
269	<
270	<	queue[size] = e;
271	<	fixUp(size);
264	>	int i = size;
265	>	if (i >= queue.length)
266	>	grow(i + 1);
267	>	size = i + 1;
268	>	if (i == 0)
269	>	queue[0] = e;
270	>	else
271	>	siftUp(i, e);
272		return true;
273		}
274
275		public E peek() {
276		if (size == 0)
277		return null;
278	<	return (E) queue[1];
278	>	return (E) queue[0];
279		}
280
281		private int indexOf(Object o) {
282	<	if (o == null)
283	<	return -1;
284	<	for (int i = 1; i <= size; i++)
285	<	if (o.equals(queue[i]))
286	<	return i;
282	>	if (o != null) {
283	>	for (int i = 0; i < size; i++)
284	>	if (o.equals(queue[i]))
285	>	return i;
286	>	}
287		return -1;
288		}
289
#	Line 350 | Line 307 | public class PriorityQueue<E> extends Ab
307		}
308		}
309
310	+	/**
311	+	* Version of remove using reference equality, not equals.
312	+	* Needed by iterator.remove
313	+	*
314	+	* @param o element to be removed from this queue, if present
315	+	* @return <tt>true</tt> if removed.
316	+	*/
317	+	boolean removeEq(Object o) {
318	+	for (int i = 0; i < size; i++) {
319	+	if (o == queue[i]) {
320	+	removeAt(i);
321	+	return true;
322	+	}
323	+	}
324	+	return false;
325	+	}
326	+
327		/**
328		* Returns <tt>true</tt> if this queue contains the specified element.
329		* More formally, returns <tt>true</tt> if and only if this queue contains
#	Line 373 | Line 347 | public class PriorityQueue<E> extends Ab
347		* @return an array containing all of the elements in this queue.
348		*/
349		public Object[] toArray() {
350	<	return Arrays.copyOfRange(queue, 1, size+1);
350	>	return Arrays.copyOf(queue, size);
351		}
352
353		/**
#	Line 403 | Line 377 | public class PriorityQueue<E> extends Ab
377		public <T> T[] toArray(T[] a) {
378		if (a.length < size)
379		// Make a new array of a's runtime type, but my contents:
380	<	return (T[]) Arrays.copyOfRange(queue, 1, size+1, a.getClass());
381	<	System.arraycopy(queue, 1, a, 0, size);
380	>	return (T[]) Arrays.copyOf(queue, size, a.getClass());
381	>	System.arraycopy(queue, 0, a, 0, size);
382		if (a.length > size)
383		a[size] = null;
384		return a;
#	Line 420 | Line 394 | public class PriorityQueue<E> extends Ab
394		return new Itr();
395		}
396
397	<	private class Itr implements Iterator<E> {
424	<
397	>	private final class Itr implements Iterator<E> {
398		/**
399		* Index (into queue array) of element to be returned by
400		* subsequent call to next.
401		*/
402	<	private int cursor = 1;
402	>	private int cursor = 0;
403
404		/**
405		* Index of element returned by most recent call to next,
406		* unless that element came from the forgetMeNot list.
407	<	* Reset to 0 if element is deleted by a call to remove.
407	>	* Set to -1 if element is deleted by a call to remove.
408		*/
409	<	private int lastRet = 0;
409	>	private int lastRet = -1;
410
411		/**
412	<	* The modCount value that the iterator believes that the backing
440	<	* List should have.  If this expectation is violated, the iterator
441	<	* has detected concurrent modification.
442	<	*/
443	<	private int expectedModCount = modCount;
444	<
445	<	/**
446	<	* A list of elements that were moved from the unvisited portion of
412	>	* A queue of elements that were moved from the unvisited portion of
413		* the heap into the visited portion as a result of "unlucky" element
414		* removals during the iteration.  (Unlucky element removals are those
415	<	* that require a fixup instead of a fixdown.)  We must visit all of
415	>	* that require a siftup instead of a siftdown.)  We must visit all of
416		* the elements in this list to complete the iteration.  We do this
417		* after we've completed the "normal" iteration.
418		*
419		* We expect that most iterations, even those involving removals,
420		* will not use need to store elements in this field.
421		*/
422	<	private ArrayList<E> forgetMeNot = null;
422	>	private ArrayDeque<E> forgetMeNot = null;
423
424		/**
425		* Element returned by the most recent call to next iff that
426		* element was drawn from the forgetMeNot list.
427		*/
428	<	private Object lastRetElt = null;
428	>	private E lastRetElt = null;
429	>
430	>	/**
431	>	* The modCount value that the iterator believes that the backing
432	>	* List should have.  If this expectation is violated, the iterator
433	>	* has detected concurrent modification.
434	>	*/
435	>	private int expectedModCount = modCount;
436
437		public boolean hasNext() {
438	<	return cursor <= size || forgetMeNot != null;
438	>	return cursor < size ||
439	>	(forgetMeNot != null && !forgetMeNot.isEmpty());
440		}
441
442		public E next() {
443	<	checkForComodification();
444	<	E result;
445	<	if (cursor <= size) {
446	<	result = (E) queue[cursor];
447	<	lastRet = cursor++;
448	<	}
449	<	else if (forgetMeNot == null)
450	<	throw new NoSuchElementException();
451	<	else {
478	<	int remaining = forgetMeNot.size();
479	<	result = forgetMeNot.remove(remaining - 1);
480	<	if (remaining == 1)
481	<	forgetMeNot = null;
482	<	lastRet = 0;
483	<	lastRetElt = result;
443	>	if (expectedModCount != modCount)
444	>	throw new ConcurrentModificationException();
445	>	if (cursor < size)
446	>	return (E) queue[lastRet = cursor++];
447	>	if (forgetMeNot != null) {
448	>	lastRet = -1;
449	>	lastRetElt = forgetMeNot.poll();
450	>	if (lastRetElt != null)
451	>	return lastRetElt;
452		}
453	<	return result;
453	>	throw new NoSuchElementException();
454		}
455
456		public void remove() {
457	<	checkForComodification();
458	<
459	<	if (lastRet != 0) {
457	>	if (expectedModCount != modCount)
458	>	throw new ConcurrentModificationException();
459	>	if (lastRet == -1 && lastRetElt == null)
460	>	throw new IllegalStateException();
461	>	if (lastRet != -1) {
462		E moved = PriorityQueue.this.removeAt(lastRet);
463	<	lastRet = 0;
464	<	if (moved == null) {
463	>	lastRet = -1;
464	>	if (moved == null)
465		cursor--;
466	<	} else {
466	>	else {
467		if (forgetMeNot == null)
468	<	forgetMeNot = new ArrayList<E>();
468	>	forgetMeNot = new ArrayDeque<E>();
469		forgetMeNot.add(moved);
470	<	}
501	<	} else if (lastRetElt != null) {
502	<	PriorityQueue.this.remove(lastRetElt);
503	<	lastRetElt = null;
470	>	}
471		} else {
472	<	throw new IllegalStateException();
473	<	}
474	<
472	>	PriorityQueue.this.removeEq(lastRetElt);
473	>	lastRetElt = null;
474	>	}
475		expectedModCount = modCount;
476		}
477
511	–	final void checkForComodification() {
512	–	if (modCount != expectedModCount)
513	–	throw new ConcurrentModificationException();
514	–	}
478		}
479
480		public int size() {
#	Line 524 | Line 487 | public class PriorityQueue<E> extends Ab
487		*/
488		public void clear() {
489		modCount++;
490	<
528	<	// Null out element references to prevent memory leak
529	<	for (int i=1; i<=size; i++)
490	>	for (int i = 0; i < size; i++)
491		queue[i] = null;
531	–
492		size = 0;
493		}
494
495		public E poll() {
496		if (size == 0)
497		return null;
498	+	int s = --size;
499		modCount++;
500	<
501	<	E result = (E) queue[1];
502	<	queue[1] = queue[size];
503	<	queue[size--] = null;  // Drop extra ref to prevent memory leak
504	<	if (size > 1)
544	<	fixDown(1);
545	<
500	>	E result = (E)queue[0];
501	>	E x = (E)queue[s];
502	>	queue[s] = null;
503	>	if (s != 0)
504	>	siftDown(0, x);
505		return result;
506		}
507
508		/**
509	<	* Removes and returns the ith element from queue.  (Recall that queue
551	<	* is one-based, so 1 <= i <= size.)
509	>	* Removes the ith element from queue.
510		*
511	<	* Normally this method leaves the elements at positions from 1 up to i-1,
512	<	* inclusive, untouched.  Under these circumstances, it returns null.
513	<	* Occasionally, in order to maintain the heap invariant, it must move
514	<	* the last element of the list to some index in the range [2, i-1],
515	<	* and move the element previously at position (i/2) to position i.
516	<	* Under these circumstances, this method returns the element that was
517	<	* previously at the end of the list and is now at some position between
518	<	* 2 and i-1 inclusive.
511	>	* Normally this method leaves the elements at up to i-1,
512	>	* inclusive, untouched.  Under these circumstances, it returns
513	>	* null.  Occasionally, in order to maintain the heap invariant,
514	>	* it must swap a later element of the list with one earlier than
515	>	* i.  Under these circumstances, this method returns the element
516	>	* that was previously at the end of the list and is now at some
517	>	* position before i. This fact is used by iterator.remove so as to
518	>	* avoid missing traverseing elements.
519		*/
520		private E removeAt(int i) {
521	<	assert i > 0 && i <= size;
521	>	assert i >= 0 && i < size;
522		modCount++;
523	<
524	<	E moved = (E) queue[size];
525	<	queue[i] = moved;
526	<	queue[size--] = null;  // Drop extra ref to prevent memory leak
527	<	if (i <= size) {
528	<	fixDown(i);
523	>	int s = --size;
524	>	if (s == i) // removed last element
525	>	queue[i] = null;
526	>	else {
527	>	E moved = (E) queue[s];
528	>	queue[s] = null;
529	>	siftDown(i, moved);
530		if (queue[i] == moved) {
531	<	fixUp(i);
531	>	siftUp(i, moved);
532		if (queue[i] != moved)
533		return moved;
534		}
#	Line 578 | Line 537 | public class PriorityQueue<E> extends Ab
537		}
538
539		/**
540	<	* Establishes the heap invariant (described above) assuming the heap
541	<	* satisfies the invariant except possibly for the leaf-node indexed by k
542	<	* (which may have a nextExecutionTime less than its parent's).
543	<	*
544	<	* This method functions by "promoting" queue[k] up the hierarchy
545	<	* (by swapping it with its parent) repeatedly until queue[k]
546	<	* is greater than or equal to its parent.
547	<	*/
548	<	private void fixUp(int k) {
549	<	if (comparator == null) {
550	<	while (k > 1) {
551	<	int j = k >> 1;
552	<	if (((Comparable<? super E>)queue[j]).compareTo((E)queue[k]) <= 0)
553	<	break;
554	<	Object tmp = queue[j];  queue[j] = queue[k]; queue[k] = tmp;
555	<	k = j;
556	<	}
557	<	} else {
558	<	while (k > 1) {
559	<	int j = k >>> 1;
560	<	if (comparator.compare((E)queue[j], (E)queue[k]) <= 0)
561	<	break;
562	<	Object tmp = queue[j];  queue[j] = queue[k]; queue[k] = tmp;
563	<	k = j;
564	<	}
565	<	}
566	<	}
567	<
568	<	/**
569	<	* Establishes the heap invariant (described above) in the subtree
570	<	* rooted at k, which is assumed to satisfy the heap invariant except
571	<	* possibly for node k itself (which may be greater than its children).
572	<	*
573	<	* This method functions by "demoting" queue[k] down the hierarchy
574	<	* (by swapping it with its smaller child) repeatedly until queue[k]
575	<	* is less than or equal to its children.
576	<	*/
577	<	private void fixDown(int k) {
578	<	int j;
579	<	if (comparator == null) {
580	<	while ((j = k << 1) <= size && (j > 0)) {
581	<	if (j<size &&
582	<	((Comparable<? super E>)queue[j]).compareTo((E)queue[j+1]) > 0)
583	<	j++; // j indexes smallest kid
584	<
585	<	if (((Comparable<? super E>)queue[k]).compareTo((E)queue[j]) <= 0)
586	<	break;
587	<	Object tmp = queue[j];  queue[j] = queue[k]; queue[k] = tmp;
588	<	k = j;
589	<	}
590	<	} else {
591	<	while ((j = k << 1) <= size && (j > 0)) {
592	<	if (j<size &&
593	<	comparator.compare((E)queue[j], (E)queue[j+1]) > 0)
594	<	j++; // j indexes smallest kid
595	<	if (comparator.compare((E)queue[k], (E)queue[j]) <= 0)
596	<	break;
597	<	Object tmp = queue[j];  queue[j] = queue[k]; queue[k] = tmp;
598	<	k = j;
599	<	}
540	>	* Inserts item x at position k, maintaining heap invariant by
541	>	* promoting x up the tree until it is greater than or equal to
542	>	* its parent, or is the root.
543	>	*
544	>	* To simplify and speed up coercions and comparisons. the
545	>	* Comparable and Comparator versions are separated into different
546	>	* methods that are otherwise identical. (Similarly for siftDown.)
547	>	*
548	>	* @param k the position to fill
549	>	* @param x the item to insert
550	>	*/
551	>	private void siftUp(int k, E x) {
552	>	if (comparator != null)
553	>	siftUpUsingComparator(k, x);
554	>	else
555	>	siftUpComparable(k, x);
556	>	}
557	>
558	>	private void siftUpComparable(int k, E x) {
559	>	Comparable<? super E> key = (Comparable<? super E>) x;
560	>	while (k > 0) {
561	>	int parent = (k - 1) >>> 1;
562	>	Object e = queue[parent];
563	>	if (key.compareTo((E)e) >= 0)
564	>	break;
565	>	queue[k] = e;
566	>	k = parent;
567	>	}
568	>	queue[k] = key;
569	>	}
570	>
571	>	private void siftUpUsingComparator(int k, E x) {
572	>	while (k > 0) {
573	>	int parent = (k - 1) >>> 1;
574	>	Object e = queue[parent];
575	>	if (comparator.compare(x, (E)e) >= 0)
576	>	break;
577	>	queue[k] = e;
578	>	k = parent;
579	>	}
580	>	queue[k] = x;
581	>	}
582	>
583	>	/**
584	>	* Inserts item x at position k, maintaining heap invariant by
585	>	* demoting x down the tree repeatedly until it is less than or
586	>	* equal to its children or is a leaf.
587	>	*
588	>	* @param k the position to fill
589	>	* @param x the item to insert
590	>	*/
591	>	private void siftDown(int k, E x) {
592	>	if (comparator != null)
593	>	siftDownUsingComparator(k, x);
594	>	else
595	>	siftDownComparable(k, x);
596	>	}
597	>
598	>	private void siftDownComparable(int k, E x) {
599	>	Comparable<? super E> key = (Comparable<? super E>)x;
600	>	int half = size >>> 1;        // loop while a non-leaf
601	>	while (k < half) {
602	>	int child = (k << 1) + 1; // assume left child is least
603	>	Object c = queue[child];
604	>	int right = child + 1;
605	>	if (right < size &&
606	>	((Comparable<? super E>)c).compareTo((E)queue[right]) > 0)
607	>	c = queue[child = right];
608	>	if (key.compareTo((E)c) <= 0)
609	>	break;
610	>	queue[k] = c;
611	>	k = child;
612	>	}
613	>	queue[k] = key;
614	>	}
615	>
616	>	private void siftDownUsingComparator(int k, E x) {
617	>	int half = size >>> 1;
618	>	while (k < half) {
619	>	int child = (k << 1) + 1;
620	>	Object c = queue[child];
621	>	int right = child + 1;
622	>	if (right < size &&
623	>	comparator.compare((E)c, (E)queue[right]) > 0)
624	>	c = queue[child = right];
625	>	if (comparator.compare(x, (E)c) <= 0)
626	>	break;
627	>	queue[k] = c;
628	>	k = child;
629		}
630	+	queue[k] = x;
631		}
632
633		/**
#	Line 646 | Line 635 | public class PriorityQueue<E> extends Ab
635		* assuming nothing about the order of the elements prior to the call.
636		*/
637		private void heapify() {
638	<	for (int i = size/2; i >= 1; i--)
639	<	fixDown(i);
638	>	for (int i = (size >>> 1) - 1; i >= 0; i--)
639	>	siftDown(i, (E)queue[i]);
640		}
641
642		/**
#	Line 678 | Line 667 | public class PriorityQueue<E> extends Ab
667		s.defaultWriteObject();
668
669		// Write out array length
670	<	s.writeInt(queue.length);
670	>	// For compatibility with 1.5 version, must be at least 2.
671	>	s.writeInt(Math.max(2, queue.length));
672
673		// Write out all elements in the proper order.
674	<	for (int i=1; i<=size; i++)
674	>	for (int i=0; i<size; i++)
675		s.writeObject(queue[i]);
676		}
677
#	Line 700 | Line 690 | public class PriorityQueue<E> extends Ab
690		queue = new Object[arrayLength];
691
692		// Read in all elements in the proper order.
693	<	for (int i=1; i<=size; i++)
693	>	for (int i=0; i<size; i++)
694		queue[i] = (E) s.readObject();
695		}
696

Diff Legend

–	Removed lines
+	Added lines
<	Changed lines
>	Changed lines