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.impl; 018 019import java.util.ArrayList; 020import java.util.Collection; 021import java.util.Map; 022import java.util.concurrent.ArrayBlockingQueue; 023import java.util.concurrent.BlockingQueue; 024 025import org.apache.camel.spi.ServicePool; 026import org.apache.camel.support.ServiceSupport; 027import org.apache.camel.util.LRUCache; 028import org.apache.camel.util.ServiceHelper; 029import org.slf4j.Logger; 030import org.slf4j.LoggerFactory; 031 032/** 033 * Default implementation to inherit for a basic service pool. 034 * 035 * @version 036 */ 037public abstract class DefaultServicePool<Key, Service> extends ServiceSupport implements ServicePool<Key, Service> { 038 protected final Logger log = LoggerFactory.getLogger(getClass()); 039 protected final Map<Key, BlockingQueue<Service>> pool; 040 protected int capacity = 100; 041 042 protected DefaultServicePool() { 043 this.pool = new LRUCache(capacity); 044 } 045 046 public DefaultServicePool(int capacity) { 047 this.capacity = capacity; 048 this.pool = new LRUCache(capacity); 049 } 050 051 public int getCapacity() { 052 return capacity; 053 } 054 055 public void setCapacity(int capacity) { 056 this.capacity = capacity; 057 } 058 059 public synchronized int size() { 060 int size = 0; 061 for (BlockingQueue<Service> entry : pool.values()) { 062 size += entry.size(); 063 } 064 return size; 065 } 066 067 public synchronized Service addAndAcquire(Key key, Service service) { 068 BlockingQueue<Service> entry = pool.get(key); 069 if (entry == null) { 070 entry = new ArrayBlockingQueue<Service>(capacity); 071 pool.put(key, entry); 072 } 073 log.trace("AddAndAcquire key: {} service: {}", key, service); 074 075 // test if queue will be full 076 if (entry.size() >= capacity) { 077 throw new IllegalStateException("Queue full"); 078 } 079 return service; 080 } 081 082 public synchronized Service acquire(Key key) { 083 BlockingQueue<Service> services = pool.get(key); 084 if (services == null || services.isEmpty()) { 085 log.trace("No free services in pool to acquire for key: {}", key); 086 return null; 087 } 088 089 Service answer = services.poll(); 090 log.trace("Acquire: {} service: {}", key, answer); 091 return answer; 092 } 093 094 public synchronized void release(Key key, Service service) { 095 log.trace("Release: {} service: {}", key, service); 096 BlockingQueue<Service> services = pool.get(key); 097 if (services != null) { 098 services.add(service); 099 } 100 } 101 102 public void purge() { 103 pool.clear(); 104 } 105 106 protected void doStart() throws Exception { 107 log.debug("Starting service pool: {}", this); 108 } 109 110 protected void doStop() throws Exception { 111 log.debug("Stopping service pool: {}", this); 112 for (BlockingQueue<Service> entry : pool.values()) { 113 Collection<Service> values = new ArrayList<Service>(); 114 entry.drainTo(values); 115 ServiceHelper.stopServices(values); 116 entry.clear(); 117 } 118 pool.clear(); 119 } 120 121}