001package org.apache.commons.jcs.auxiliary; 002 003/* 004 * Licensed to the Apache Software Foundation (ASF) under one 005 * or more contributor license agreements. See the NOTICE file 006 * distributed with this work for additional information 007 * regarding copyright ownership. The ASF licenses this file 008 * to you under the Apache License, Version 2.0 (the 009 * "License"); you may not use this file except in compliance 010 * with the License. You may obtain a copy of the License at 011 * 012 * http://www.apache.org/licenses/LICENSE-2.0 013 * 014 * Unless required by applicable law or agreed to in writing, 015 * software distributed under the License is distributed on an 016 * "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY 017 * KIND, either express or implied. See the License for the 018 * specific language governing permissions and limitations 019 * under the License. 020 */ 021 022import org.apache.commons.jcs.engine.behavior.ICache; 023import org.apache.commons.jcs.engine.behavior.IElementSerializer; 024import org.apache.commons.jcs.engine.logging.behavior.ICacheEventLogger; 025import org.apache.commons.jcs.engine.stats.behavior.IStats; 026 027import java.io.IOException; 028import java.util.Set; 029 030/** 031 * Tag interface for auxiliary caches. Currently this provides no additional methods over what is in 032 * ICache, but I anticipate that will change. For example, there will be a mechanism for determining 033 * the type (disk/lateral/remote) of the auxiliary here -- and the existing getCacheType will be 034 * removed from ICache. 035 */ 036public interface AuxiliaryCache<K, V> 037 extends ICache<K, V> 038{ 039 /** 040 * Get a set of the keys for all elements in the auxiliary cache. 041 * <p> 042 * @return a set of the key type 043 * TODO This should probably be done in chunks with a range passed in. This 044 * will be a problem if someone puts a 1,000,000 or so items in a 045 * region. 046 * @throws IOException if access to the auxiliary cache fails 047 */ 048 Set<K> getKeySet() throws IOException; 049 050 /** 051 * @return the historical and statistical data for a region's auxiliary cache. 052 */ 053 IStats getStatistics(); 054 055 /** 056 * This returns the generic attributes for an auxiliary cache. Most implementations will cast 057 * this to a more specific type. 058 * <p> 059 * @return the attributes for the auxiliary cache 060 */ 061 AuxiliaryCacheAttributes getAuxiliaryCacheAttributes(); 062 063 /** 064 * Allows you to inject a custom serializer. A good example would be a compressing standard 065 * serializer. 066 * <p> 067 * @param elementSerializer 068 */ 069 void setElementSerializer( IElementSerializer elementSerializer ); 070 071 /** 072 * Every Auxiliary must allow for the use of an event logger. 073 * <p> 074 * @param cacheEventLogger 075 */ 076 void setCacheEventLogger( ICacheEventLogger cacheEventLogger ); 077}