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 */ 017 package org.apache.camel.util; 018 019 import java.util.HashMap; 020 import java.util.Iterator; 021 import java.util.Map; 022 import java.util.Set; 023 import java.util.SortedSet; 024 import java.util.TreeSet; 025 import java.util.concurrent.ScheduledExecutorService; 026 import java.util.concurrent.TimeUnit; 027 028 import org.apache.commons.logging.Log; 029 import org.apache.commons.logging.LogFactory; 030 031 /** 032 * 033 * @version $Revision: 642753 $ 034 */ 035 public class DefaultTimeoutMap implements TimeoutMap, Runnable { 036 037 private static final Log LOG = LogFactory.getLog(DefaultTimeoutMap.class); 038 039 private Map map = new HashMap(); 040 private SortedSet index = new TreeSet(); 041 private ScheduledExecutorService executor; 042 private long purgePollTime; 043 044 public DefaultTimeoutMap() { 045 this(null, 1000L); 046 } 047 048 public DefaultTimeoutMap(ScheduledExecutorService executor, long requestMapPollTimeMillis) { 049 this.executor = executor; 050 this.purgePollTime = requestMapPollTimeMillis; 051 schedulePoll(); 052 } 053 054 public Object get(Object key) { 055 TimeoutMapEntry entry = null; 056 synchronized (map) { 057 entry = (TimeoutMapEntry) map.get(key); 058 if (entry == null) { 059 return null; 060 } 061 index.remove(entry); 062 updateExpireTime(entry); 063 index.add(entry); 064 } 065 return entry.getValue(); 066 } 067 068 public void put(Object key, Object value, long timeoutMillis) { 069 TimeoutMapEntry entry = new TimeoutMapEntry(key, value, timeoutMillis); 070 synchronized (map) { 071 Object oldValue = map.put(key, entry); 072 if (oldValue != null) { 073 index.remove(oldValue); 074 } 075 updateExpireTime(entry); 076 index.add(entry); 077 } 078 } 079 080 public void remove(Object id) { 081 synchronized (map) { 082 TimeoutMapEntry entry = (TimeoutMapEntry) map.remove(id); 083 if (entry != null) { 084 index.remove(entry); 085 } 086 } 087 } 088 089 /** 090 * Returns a copy of the keys in the map 091 */ 092 public Object[] getKeys() { 093 Object[] keys = null; 094 synchronized (map) { 095 Set keySet = map.keySet(); 096 keys = new String[keySet.size()]; 097 keySet.toArray(keys); 098 } 099 return keys; 100 } 101 102 /** 103 * The timer task which purges old requests and schedules another poll 104 */ 105 public void run() { 106 purge(); 107 schedulePoll(); 108 } 109 110 /** 111 * Purges any old entries from the map 112 */ 113 public void purge() { 114 long now = currentTime(); 115 synchronized (map) { 116 for (Iterator iter = index.iterator(); iter.hasNext();) { 117 TimeoutMapEntry entry = (TimeoutMapEntry) iter.next(); 118 if (entry == null) { 119 break; 120 } 121 if (entry.getExpireTime() < now) { 122 if (isValidForEviction(entry)) { 123 if (LOG.isDebugEnabled()) { 124 LOG.debug("Evicting inactive request for correlationID: " + entry); 125 } 126 map.remove(entry.getKey()); 127 iter.remove(); 128 } 129 } else { 130 break; 131 } 132 } 133 } 134 } 135 136 // Properties 137 // ------------------------------------------------------------------------- 138 public long getPurgePollTime() { 139 return purgePollTime; 140 } 141 142 /** 143 * Sets the next purge poll time in milliseconds 144 */ 145 public void setPurgePollTime(long purgePollTime) { 146 this.purgePollTime = purgePollTime; 147 } 148 149 public ScheduledExecutorService getExecutor() { 150 return executor; 151 } 152 153 /** 154 * Sets the executor used to schedule purge events of inactive requests 155 */ 156 public void setExecutor(ScheduledExecutorService executor) { 157 this.executor = executor; 158 } 159 160 // Implementation methods 161 // ------------------------------------------------------------------------- 162 163 /** 164 * lets schedule each time to allow folks to change the time at runtime 165 */ 166 protected void schedulePoll() { 167 if (executor != null) { 168 executor.schedule(this, purgePollTime, TimeUnit.MILLISECONDS); 169 } 170 } 171 172 /** 173 * A hook to allow derivations to avoid evicting the current entry 174 */ 175 protected boolean isValidForEviction(TimeoutMapEntry entry) { 176 return true; 177 } 178 179 protected void updateExpireTime(TimeoutMapEntry entry) { 180 long now = currentTime(); 181 entry.setExpireTime(entry.getTimeout() + now); 182 } 183 184 protected long currentTime() { 185 return System.currentTimeMillis(); 186 } 187 }