001package org.apache.commons.jcs.engine.behavior; 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.CacheStatus; 023import org.apache.commons.jcs.engine.match.behavior.IKeyMatcher; 024 025import java.io.IOException; 026import java.util.Map; 027import java.util.Set; 028 029/** 030 * This is the top level interface for all cache like structures. It defines the methods used 031 * internally by JCS to access, modify, and instrument such structures. 032 * 033 * This allows for a suite of reusable components for accessing such structures, for example 034 * asynchronous access via an event queue. 035 */ 036public interface ICache<K, V> 037 extends ICacheType 038{ 039 /** 040 * Puts an item to the cache. 041 * 042 * @param element 043 * @throws IOException 044 */ 045 void update( ICacheElement<K, V> element ) 046 throws IOException; 047 048 /** 049 * Gets an item from the cache. 050 * 051 * @param key 052 * @return a cache element, or null if there is no data in cache for this key 053 * @throws IOException 054 */ 055 ICacheElement<K, V> get( K key ) 056 throws IOException; 057 058 /** 059 * Gets multiple items from the cache based on the given set of keys. 060 * 061 * @param keys 062 * @return a map of K key to ICacheElement<K, V> element, or an empty map if there is no data in cache for any of these keys 063 * @throws IOException 064 */ 065 Map<K, ICacheElement<K, V>> getMultiple(Set<K> keys) 066 throws IOException; 067 068 /** 069 * Gets items from the cache matching the given pattern. Items from memory will replace those from remote sources. 070 * 071 * This only works with string keys. It's too expensive to do a toString on every key. 072 * 073 * Auxiliaries will do their best to handle simple expressions. For instance, the JDBC disk cache will convert * to % and . to _ 074 * 075 * @param pattern 076 * @return a map of K key to ICacheElement<K, V> element, or an empty map if there is no data matching the pattern. 077 * @throws IOException 078 */ 079 Map<K, ICacheElement<K, V>> getMatching(String pattern) 080 throws IOException; 081 082 /** 083 * Removes an item from the cache. 084 * 085 * @param key 086 * @return false if there was an error in removal 087 * @throws IOException 088 */ 089 boolean remove( K key ) 090 throws IOException; 091 092 /** 093 * Removes all cached items from the cache. 094 * 095 * @throws IOException 096 */ 097 void removeAll() 098 throws IOException; 099 100 /** 101 * Prepares for shutdown. 102 * @throws IOException 103 */ 104 void dispose() 105 throws IOException; 106 107 /** 108 * Returns the current cache size in number of elements. 109 * 110 * @return number of elements 111 */ 112 int getSize(); 113 114 /** 115 * Returns the cache status. 116 * 117 * @return Alive or Error 118 */ 119 CacheStatus getStatus(); 120 121 /** 122 * Returns the cache stats. 123 * 124 * @return String of important historical information. 125 */ 126 String getStats(); 127 128 /** 129 * Returns the cache name. 130 * 131 * @return usually the region name. 132 */ 133 String getCacheName(); 134 135 /** 136 * Sets the key matcher used by get matching. 137 * 138 * @param keyMatcher 139 */ 140 void setKeyMatcher( IKeyMatcher<K> keyMatcher ); 141}