1 pnkfelix 1.1.2.1 // PriorityQueue.java, created Tue Jun 1 13:43:17 1999 by pnkfelix
2 cananian 1.1.2.3 // Copyright (C) 1999 Felix S. Klock II <pnkfelix@mit.edu>
3 pnkfelix 1.1.2.1 // Licensed under the terms of the GNU GPL; see COPYING for details.
4 pnkfelix 1.1.2.1 package harpoon.Util;
5 pnkfelix 1.1.2.1
6 pnkfelix 1.1.2.1 import java.util.Collection;
7 pnkfelix 1.1.2.1
8 pnkfelix 1.1.2.1 /**
9 pnkfelix 1.1.2.1 * <code>MaxPriorityQueue</code> maintains a <code>Collection</code> of
10 pnkfelix 1.1.2.1 * <code>Object</code>s, each with an associated priority.
11 pnkfelix 1.1.2.1 * Implementations should make the <code>peekMax</code> and
12 pnkfelix 1.1.2.1 * <code>removeMax</code> operations efficient. Implementations
13 pnkfelix 1.1.2.1 * need not implement the Object-addition operations of the
14 pnkfelix 1.1.2.1 * <code>Collection</code> interface, since they do not associate each
15 pnkfelix 1.1.2.1 * added <code>Object</code> with a priority.
16 pnkfelix 1.1.2.1 *
17 cananian 1.1.2.3 * @author Felix S. Klock II <pnkfelix@mit.edu>
18 ovy 1.3 * @version $Id: MaxPriorityQueue.java,v 1.3 2002/04/23 22:29:05 ovy Exp $
19 pnkfelix 1.1.2.1 */
20 pnkfelix 1.1.2.1 public interface MaxPriorityQueue extends Collection {
21 pnkfelix 1.1.2.2
22 pnkfelix 1.1.2.2 /** Inserts <code>item</code> into this, assigning it priority
23 pnkfelix 1.1.2.2 <code>priority</code>.
24 pnkfelix 1.1.2.2 @param item <code>Object</code> being inserted
25 pnkfelix 1.1.2.2 @param priority Priority of <code>item</code>
26 pnkfelix 1.1.2.2 */
27 ovy 1.3 boolean insert(Object item, int priority);
28 pnkfelix 1.1.2.1
29 pnkfelix 1.1.2.2 /** Returns the <code>Object</code> in <code>this</code> with the
30 pnkfelix 1.1.2.2 highest priority.
31 pnkfelix 1.1.2.2 */
32 pnkfelix 1.1.2.1 Object peekMax();
33 pnkfelix 1.1.2.1
34 pnkfelix 1.1.2.2 /** Returns and removes the <code>Object</code> in
35 pnkfelix 1.1.2.2 <code>this</code> with the highest priority.
36 pnkfelix 1.1.2.2 */
37 pnkfelix 1.1.2.1 Object deleteMax();
38 ovy 1.3
39 ovy 1.3
40 ovy 1.3 /** Returns the priority currently associated with this item.
41 ovy 1.3 */
42 ovy 1.3 int getPriority(Object item);
43 ovy 1.3
44 ovy 1.3 /** Changes the priority of this <code>Object</code>
45 ovy 1.3 to the new, specified value, and returns the old value
46 ovy 1.3 */
47 ovy 1.3 int setPriority(Object item, int newPriority);
48 ovy 1.3
49 ovy 1.3 /** Change the priority of this element by the specified delta.
50 ovy 1.3 This is equivalent to <code>setPriority(item, getPriority(item)+delta).
51 ovy 1.3 It might save time in some implementations.
52 ovy 1.3 */
53 ovy 1.3 void changePriority(Object item, int delta);
54 pnkfelix 1.1.2.1
55 cananian 1.2 }