1 /***
2 *
3 * Copyright 2004 Hiram Chirino
4 *
5 * Licensed under the Apache License, Version 2.0 (the "License");
6 * you may not use this file except in compliance with the License.
7 * You may obtain a copy of the License at
8 *
9 * http://www.apache.org/licenses/LICENSE-2.0
10 *
11 * Unless required by applicable law or agreed to in writing, software
12 * distributed under the License is distributed on an "AS IS" BASIS,
13 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
14 * See the License for the specific language governing permissions and
15 * limitations under the License.
16 *
17 **/
18 package org.codehaus.activemq.store.cache;
19
20 import org.codehaus.activemq.message.ActiveMQMessage;
21 import org.codehaus.activemq.util.LRUCache;
22
23 /***
24 * A simple cache that stores messages in memory. Cache entries are evicted
25 * when they they get to old (A LRU cache is used).
26 *
27 * @version $Revision: 1.2 $
28 */
29 public class SimpleMessageCache implements MessageCache {
30
31 private final LRUCache messages;
32
33 public SimpleMessageCache() {
34 this(1000);
35 }
36
37 public SimpleMessageCache(int cacheSize) {
38 this.messages = new LRUCache(cacheSize);
39 }
40
41 /***
42 * Gets a message that was previously <code>put</code> into this object.
43 *
44 * @param msgid
45 * @return null if the message was not previously put or if the message has expired out of the cache.
46 */
47 synchronized public ActiveMQMessage get(String msgid) {
48 return (ActiveMQMessage) messages.get(msgid);
49 }
50
51 /***
52 * Puts a message into the cache.
53 *
54 * @param messageID
55 * @param message
56 */
57 synchronized public void put(String messageID, ActiveMQMessage message) {
58 messages.put(messageID, message);
59 }
60
61 /***
62 * Remvoes a message from the cache.
63 *
64 * @param messageID
65 */
66 synchronized public void remove(String messageID) {
67 messages.remove(messageID);
68 }
69
70 }