1 package org.apache.commons.jcs3.engine.memory.mru; 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.jcs3.engine.behavior.ICacheElement; 25 import org.apache.commons.jcs3.engine.memory.AbstractDoubleLinkedListMemoryCache; 26 import org.apache.commons.jcs3.engine.memory.util.MemoryElementDescriptor; 27 28 /** 29 * The most recently used items move to the front of the list and get spooled to disk if the cache 30 * hub is configured to use a disk cache. 31 */ 32 public class MRUMemoryCache<K, V> 33 extends AbstractDoubleLinkedListMemoryCache<K, V> 34 { 35 /** 36 * Adds the item to the front of the list. A put doesn't count as a usage. 37 * <p> 38 * It's not clear if the put operation should be different. Perhaps this should remove the oldest 39 * if full, and then put. 40 * <p> 41 * @param ce 42 * @return MemoryElementDescriptor the new node 43 * @throws IOException 44 */ 45 @Override 46 protected MemoryElementDescriptor<K, V> adjustListForUpdate( final ICacheElement<K, V> ce ) 47 throws IOException 48 { 49 return addFirst( ce ); 50 } 51 52 /** 53 * Makes the item the last in the list. 54 * <p> 55 * @param me 56 */ 57 @Override 58 protected void adjustListForGet( final MemoryElementDescriptor<K, V> me ) 59 { 60 list.makeLast( me ); 61 } 62 }