KickJava   Java API By Example, From Geeks To Geeks.

Java > Open Source Codes > org > apache > activemq > memory > CacheEntry


1 /**
2  *
3  * Licensed to the Apache Software Foundation (ASF) under one or more
4  * contributor license agreements. See the NOTICE file distributed with
5  * this work for additional information regarding copyright ownership.
6  * The ASF licenses this file to You under the Apache License, Version 2.0
7  * (the "License"); you may not use this file except in compliance with
8  * the License. You may obtain a copy of the License at
9  *
10  * http://www.apache.org/licenses/LICENSE-2.0
11  *
12  * Unless required by applicable law or agreed to in writing, software
13  * distributed under the License is distributed on an "AS IS" BASIS,
14  * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
15  * See the License for the specific language governing permissions and
16  * limitations under the License.
17  */
18 package org.apache.activemq.memory;
19
20 public class CacheEntry {
21     
22     public final Object JavaDoc key;
23     public final Object JavaDoc value;
24     
25     public CacheEntry next;
26     public CacheEntry previous;
27     public CacheEntryList owner;
28     
29     public CacheEntry(Object JavaDoc key, Object JavaDoc value) {
30         this.key=key;
31         this.value = value;
32     }
33
34     /**
35      *
36      * @param entry
37      * @return false if you are trying to remove the tail pointer.
38      */
39     public boolean remove() {
40                 
41         // Cannot remove if this is a tail pointer.
42 // Or not linked.
43 if( owner==null || this.key==null || this.next==null )
44             return false;
45         
46         synchronized( owner.tail ) {
47             this.next.previous = this.previous;
48             this.previous.next = this.next;
49             this.owner = null;
50             this.next = this.previous = null;
51         }
52         
53         return true;
54     }
55
56 }
57
Popular Tags