1 package org.apache.commons.jcs.engine.memory.fifo;
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.io.IOException;
23
24 import org.apache.commons.jcs.engine.behavior.ICacheElement;
25 import org.apache.commons.jcs.engine.memory.AbstractDoubleLinkedListMemoryCache;
26 import org.apache.commons.jcs.engine.memory.util.MemoryElementDescriptor;
27
28 /**
29 * The items are spooled in the order they are added. No adjustments to the list are made on get.
30 */
31 public class FIFOMemoryCache<K, V>
32 extends AbstractDoubleLinkedListMemoryCache<K, V>
33 {
34 /**
35 * Puts an item to the cache. Removes any pre-existing entries of the same key from the linked
36 * list and adds this one first.
37 * <p>
38 * @param ce The cache element, or entry wrapper
39 * @return MemoryElementDescriptor the new node
40 * @throws IOException
41 */
42 @Override
43 protected MemoryElementDescriptor<K, V> adjustListForUpdate( ICacheElement<K, V> ce )
44 throws IOException
45 {
46 return addFirst( ce );
47 }
48
49 /**
50 * Does nothing.
51 * <p>
52 * @param me
53 */
54 @Override
55 protected void adjustListForGet( MemoryElementDescriptor<K, V> me )
56 {
57 // DO NOTHING
58 }
59 }