1 package org.apache.commons.jcs.utils.struct;
2
3 /*
4 * Licensed to the Apache Software Foundation (ASF) under one
5 * or more contributor license agreements. See the NOTICE file
6 * distributed with this work for additional information
7 * regarding copyright ownership. The ASF licenses this file
8 * to you under the Apache License, Version 2.0 (the
9 * "License"); you may not use this file except in compliance
10 * with the License. You may obtain a copy of the License at
11 *
12 * http://www.apache.org/licenses/LICENSE-2.0
13 *
14 * Unless required by applicable law or agreed to in writing,
15 * software distributed under the License is distributed on an
16 * "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
17 * KIND, either express or implied. See the License for the
18 * specific language governing permissions and limitations
19 * under the License.
20 */
21
22 import java.util.concurrent.atomic.AtomicInteger;
23
24 /**
25 *
26 * @author Wiktor Niesiobędzki
27 *
28 * Simple LRUMap implementation that keeps the number of the objects below or equal maxObjects
29 *
30 * @param <K>
31 * @param <V>
32 */
33 public class LRUMap<K, V> extends AbstractLRUMap<K, V>
34 {
35
36 /** if the max is less than 0, there is no limit! */
37 int maxObjects = -1;
38 AtomicInteger counter = new AtomicInteger(0);
39
40 public LRUMap()
41 {
42 super();
43 }
44
45 /**
46 *
47 * @param maxObjects
48 * maximum number to keep in the map
49 */
50 public LRUMap(int maxObjects)
51 {
52 super();
53 this.maxObjects = maxObjects;
54 }
55
56 @Override
57 public boolean shouldRemove()
58 {
59 return maxObjects > 0 && this.size() > maxObjects;
60 }
61
62 public Object getMaxCounter()
63 {
64 return maxObjects;
65 }
66 }