KickJava   Java API By Example, From Geeks To Geeks.

Java > Open Source Codes > org > aspectj > util > StackMap


1 /* -*- Mode: Java; tab-width: 4; indent-tabs-mode: nil; c-basic-offset: 4 -*-
2  *
3  * This file is part of the compiler and core tools for the AspectJ(tm)
4  * programming language; see http://aspectj.org
5  *
6  * The contents of this file are subject to the Mozilla Public License
7  * Version 1.1 (the "License"); you may not use this file except in
8  * compliance with the License. You may obtain a copy of the License at
9  * either http://www.mozilla.org/MPL/ or http://aspectj.org/MPL/.
10  *
11  * Software distributed under the License is distributed on an "AS IS" basis,
12  * WITHOUT WARRANTY OF ANY KIND, either express or implied. See the License
13  * for the specific language governing rights and limitations under the
14  * License.
15  *
16  * The Original Code is AspectJ.
17  *
18  * The Initial Developer of the Original Code is Xerox Corporation. Portions
19  * created by Xerox Corporation are Copyright (C) 1999-2002 Xerox Corporation.
20  * All Rights Reserved.
21  *
22  * Contributor(s):
23  */
24
25 package org.aspectj.util;
26
27
28 import java.util.*;
29
30 /** This needs a custom implementation for efficiency */
31 public class StackMap {
32     private Map map = new HashMap();
33     private LinkedList stack = new LinkedList();
34     
35     public StackMap() {
36         push();
37     }
38     
39     public Object JavaDoc put(Object JavaDoc key, Object JavaDoc value) {
40         ((List)stack.getLast()).add(key);
41         return map.put(key, value);
42     }
43
44     public Object JavaDoc get(Object JavaDoc key) {
45         return map.get(key);
46     }
47     
48     public void push() {
49         stack.add(new LinkedList());
50     }
51     
52     public void pop() {
53         List l = (List)stack.removeLast();
54         for (Iterator i = l.iterator(); i.hasNext(); ) {
55             //??? add an assertion that there's something to remove
56 map.remove(i.next());
57         }
58     }
59 }
60
Popular Tags