| 1 |
|
/* |
| 2 |
|
* %W% %E% |
| 3 |
|
* |
| 4 |
< |
* Copyright 2003 Sun Microsystems, Inc. All rights reserved. |
| 4 |
> |
* Copyright 2004 Sun Microsystems, Inc. All rights reserved. |
| 5 |
|
* SUN PROPRIETARY/CONFIDENTIAL. Use is subject to license terms. |
| 6 |
|
*/ |
| 7 |
|
|
| 14 |
|
* <i>natural order</i> (see {@link Comparable}), or according to a |
| 15 |
|
* {@link java.util.Comparator}, depending on which constructor is |
| 16 |
|
* used. A priority queue does not permit <tt>null</tt> elements. |
| 17 |
+ |
* A priority queue relying on natural ordering also does not |
| 18 |
+ |
* permit insertion of non-comparable objects (doing so may result |
| 19 |
+ |
* in <tt>ClassCastException</tt>). |
| 20 |
|
* |
| 21 |
|
* <p>The <em>head</em> of this queue is the <em>least</em> element |
| 22 |
|
* with respect to the specified ordering. If multiple elements are |
| 23 |
|
* tied for least value, the head is one of those elements -- ties are |
| 24 |
< |
* broken arbitrarily. The {@link #remove()} and {@link #poll()} |
| 25 |
< |
* methods remove and return the head of the queue, and the {@link |
| 26 |
< |
* #element()} and {@link #peek()} methods return, but do not delete, |
| 24 |
< |
* the head of the queue. |
| 24 |
> |
* broken arbitrarily. The queue retrieval operations <tt>poll</tt>, |
| 25 |
> |
* <tt>remove</tt>, <tt>peek</tt>, and <tt>element</tt> access the |
| 26 |
> |
* element at the head of the queue. |
| 27 |
|
* |
| 28 |
|
* <p>A priority queue is unbounded, but has an internal |
| 29 |
|
* <i>capacity</i> governing the size of an array used to store the |
| 59 |
|
* @since 1.5 |
| 60 |
|
* @version %I%, %G% |
| 61 |
|
* @author Josh Bloch |
| 62 |
+ |
* @param <E> the type of elements held in this collection |
| 63 |
|
*/ |
| 64 |
|
public class PriorityQueue<E> extends AbstractQueue<E> |
| 65 |
< |
implements Queue<E>, java.io.Serializable { |
| 65 |
> |
implements java.io.Serializable { |
| 66 |
|
|
| 67 |
|
private static final long serialVersionUID = -7720805057305804111L; |
| 68 |
|
|
| 199 |
|
public PriorityQueue(Collection<? extends E> c) { |
| 200 |
|
initializeArray(c); |
| 201 |
|
if (c instanceof SortedSet) { |
| 202 |
< |
// @fixme double-cast workaround for compiler |
| 200 |
< |
SortedSet<? extends E> s = (SortedSet<? extends E>) (SortedSet)c; |
| 202 |
> |
SortedSet<? extends E> s = (SortedSet<? extends E>)c; |
| 203 |
|
comparator = (Comparator<? super E>)s.comparator(); |
| 204 |
|
fillFromSorted(s); |
| 205 |
|
} else if (c instanceof PriorityQueue) { |
| 280 |
|
|
| 281 |
|
|
| 282 |
|
/** |
| 283 |
< |
* Inserts the specified element to this priority queue. |
| 283 |
> |
* Inserts the specified element into this priority queue. |
| 284 |
|
* |
| 285 |
|
* @return <tt>true</tt> |
| 286 |
|
* @throws ClassCastException if the specified element cannot be compared |
| 325 |
|
return offer(o); |
| 326 |
|
} |
| 327 |
|
|
| 326 |
– |
|
| 327 |
– |
/** |
| 328 |
– |
* Adds all of the elements in the specified collection to this queue. |
| 329 |
– |
* The behavior of this operation is undefined if |
| 330 |
– |
* the specified collection is modified while the operation is in |
| 331 |
– |
* progress. (This implies that the behavior of this call is undefined if |
| 332 |
– |
* the specified collection is this queue, and this queue is nonempty.) |
| 333 |
– |
* <p> |
| 334 |
– |
* This implementation iterates over the specified collection, and adds |
| 335 |
– |
* each object returned by the iterator to this collection, in turn. |
| 336 |
– |
* @param c collection whose elements are to be added to this queue |
| 337 |
– |
* @return <tt>true</tt> if this queue changed as a result of the |
| 338 |
– |
* call. |
| 339 |
– |
* @throws NullPointerException if <tt>c</tt> or any element in <tt>c</tt> |
| 340 |
– |
* is <tt>null</tt> |
| 341 |
– |
* @throws ClassCastException if any element cannot be compared |
| 342 |
– |
* with elements currently in the priority queue according |
| 343 |
– |
* to the priority queue's ordering. |
| 344 |
– |
*/ |
| 345 |
– |
public boolean addAll(Collection<? extends E> c) { |
| 346 |
– |
return super.addAll(c); |
| 347 |
– |
} |
| 348 |
– |
|
| 328 |
|
public boolean remove(Object o) { |
| 329 |
|
if (o == null) |
| 330 |
|
return false; |
