001/** 002 * Licensed to the Apache Software Foundation (ASF) under one or more 003 * contributor license agreements. See the NOTICE file distributed with 004 * this work for additional information regarding copyright ownership. 005 * The ASF licenses this file to You under the Apache License, Version 2.0 006 * (the "License"); you may not use this file except in compliance with 007 * the License. You may obtain a copy of the License at 008 * 009 * http://www.apache.org/licenses/LICENSE-2.0 010 * 011 * Unless required by applicable law or agreed to in writing, software 012 * distributed under the License is distributed on an "AS IS" BASIS, 013 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. 014 * See the License for the specific language governing permissions and 015 * limitations under the License. 016 */ 017package org.apache.camel; 018 019/** 020 * Represents a map of values which timeout after a period of inactivity. 021 * 022 * @version 023 */ 024public interface TimeoutMap<K, V> extends Runnable { 025 026 /** 027 * Looks up the value in the map by the given key. 028 * 029 * @param key the key of the value to search for 030 * @return the value for the given key or <tt>null</tt> if it is not present (or has timed out) 031 */ 032 V get(K key); 033 034 /** 035 * Returns a copy of the keys in the map 036 * 037 * @return the keys 038 */ 039 Object[] getKeys(); 040 041 /** 042 * Returns the size of the map 043 * 044 * @return the size 045 */ 046 int size(); 047 048 /** 049 * Adds the key value pair into the map such that some time after the given 050 * timeout the entry will be evicted 051 * 052 * @param key the key 053 * @param value the value 054 * @param timeoutMillis timeout in millis 055 * @return the previous value associated with <tt>key</tt>, or 056 * <tt>null</tt> if there was no mapping for <tt>key</tt>. 057 */ 058 V put(K key, V value, long timeoutMillis); 059 060 /** 061 * Adds the key value pair into the map if the specified key is not already associated with a value 062 * such that some time after the given timeout the entry will be evicted 063 * 064 * @param key the key 065 * @param value the value 066 * @param timeoutMillis timeout in millis 067 * @return the value associated with <tt>key</tt>, or 068 * <tt>null</tt> if there was no mapping for <tt>key</tt>. 069 */ 070 V putIfAbsent(K key, V value, long timeoutMillis); 071 072 /** 073 * Callback when the value has been evicted 074 * 075 * @param key the key 076 * @param value the value 077 * @return <tt>true</tt> to remove the evicted value, 078 * or <tt>false</tt> to veto the eviction and thus keep the value. 079 */ 080 boolean onEviction(K key, V value); 081 082 /** 083 * Removes the object with the given key 084 * 085 * @param key key for the object to remove 086 * @return the value for the given key or <tt>null</tt> if it is not present (or has timed out) 087 */ 088 V remove(K key); 089 090 /** 091 * Purges any old entries from the map 092 */ 093 void purge(); 094}