1 cananian 1.1 // Worklist.java, created Sat Sep 12 19:38:31 1998 by cananian
2 cananian 1.2 // Copyright (C) 1998 C. Scott Ananian <cananian@alumni.princeton.edu>
3 cananian 1.2 // Licensed under the terms of the GNU GPL; see COPYING for details.
4 cananian 1.1 package harpoon.Util;
5 cananian 1.1
6 cananian 1.1 /**
7 cananian 1.1 * A <code>Worklist</code> is a unique set.
8 cananian 1.1 *
9 cananian 1.1 * @author C. Scott Ananian <cananian@alumni.princeton.edu>
10 cananian 1.4 * @version $Id: Worklist.java,v 1.4 2002/04/10 03:07:05 cananian Exp $
11 cananian 1.1 */
12 cananian 1.3.2.1 public interface Worklist<E> {
13 pnkfelix 1.2.2.3
14 pnkfelix 1.2.2.3 /** Pushes an item onto the Worklist if it is not already there.
15 pnkfelix 1.2.2.3 <BR> <B>modifies:</B> <code>this</code>
16 pnkfelix 1.2.2.3 <BR> <B>effects:</B> If <code>item</code> is not already an
17 pnkfelix 1.2.2.3 element of <code>this</code>, adds
18 pnkfelix 1.2.2.5 <code>item</code> to <code>this</code>.
19 pnkfelix 1.2.2.5 Else does nothing.
20 pnkfelix 1.2.2.3 */
21 cananian 1.3.2.1 public void push(E item);
22 cananian 1.1
23 pnkfelix 1.2.2.4 /** Removes some item from the Worklist and return it.
24 pnkfelix 1.2.2.3 <BR> <B>modifies:</B> <code>this</code>
25 pnkfelix 1.2.2.4 <BR> <B>effects:</B> If there exists an <code>Object</code>,
26 pnkfelix 1.2.2.4 <code>item</code>, that is an element of
27 pnkfelix 1.2.2.4 <code>this</code>, removes
28 pnkfelix 1.2.2.5 <code>item</code> from <code>this</code>
29 pnkfelix 1.2.2.5 and returns <code>item</code>. Else does
30 pnkfelix 1.2.2.5 nothing.
31 pnkfelix 1.2.2.3 */
32 cananian 1.3.2.1 public E pull();
33 pnkfelix 1.2.2.3
34 pnkfelix 1.2.2.3 /** Determines if the Worklist contains an item.
35 pnkfelix 1.2.2.3 <BR> <B>effects:</B> If <code>item</code> is an element of
36 pnkfelix 1.2.2.3 <code>this</code>, returns true.
37 pnkfelix 1.2.2.3 Else returns false.
38 pnkfelix 1.2.2.3 */
39 cananian 1.1 public boolean contains(Object item);
40 pnkfelix 1.2.2.3
41 pnkfelix 1.2.2.3 /** Determines if there are any more items left in the Worklist.
42 pnkfelix 1.2.2.3 <BR> <B>effects:</B> If <code>this</code> has any elements,
43 pnkfelix 1.2.2.3 returns true. Else returns false.
44 pnkfelix 1.2.2.3 */
45 cananian 1.1 public boolean isEmpty();
46 cananian 1.1 }
47 cananian 1.3