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.activemq.xbean;
018
019import java.util.HashMap;
020
021import org.apache.activemq.broker.BrokerService;
022import org.springframework.beans.factory.DisposableBean;
023import org.springframework.beans.factory.FactoryBean;
024import org.springframework.beans.factory.InitializingBean;
025import org.springframework.core.io.Resource;
026
027/**
028 * Used to share a single broker even if you have multiple broker bean
029 * definitions. A use case is where you have multiple web applications that want
030 * to start an embedded broker but only the first one to deploy should actually
031 * start it.
032 * 
033 * 
034 */
035public class PooledBrokerFactoryBean implements FactoryBean, InitializingBean, DisposableBean {
036
037    static final HashMap<String, SharedBroker> SHARED_BROKER_MAP = new HashMap<String, SharedBroker>();
038
039    private boolean start;
040    private Resource config;
041
042    static class SharedBroker {
043        BrokerFactoryBean factory;
044        int refCount;
045    }
046
047    public void afterPropertiesSet() throws Exception {
048        synchronized (SHARED_BROKER_MAP) {
049            SharedBroker sharedBroker = SHARED_BROKER_MAP.get(config.getFilename());
050            if (sharedBroker == null) {
051                sharedBroker = new SharedBroker();
052                sharedBroker.factory = new BrokerFactoryBean();
053                sharedBroker.factory.setConfig(config);
054                sharedBroker.factory.setStart(start);
055                sharedBroker.factory.afterPropertiesSet();
056                SHARED_BROKER_MAP.put(config.getFilename(), sharedBroker);
057            }
058            sharedBroker.refCount++;
059        }
060    }
061
062    public void destroy() throws Exception {
063        synchronized (SHARED_BROKER_MAP) {
064            SharedBroker sharedBroker = SHARED_BROKER_MAP.get(config.getFilename());
065            if (sharedBroker != null) {
066                sharedBroker.refCount--;
067                if (sharedBroker.refCount == 0) {
068                    sharedBroker.factory.destroy();
069                    SHARED_BROKER_MAP.remove(config.getFilename());
070                }
071            }
072        }
073    }
074
075    public Resource getConfig() {
076        return config;
077    }
078
079    public Object getObject() throws Exception {
080        synchronized (SHARED_BROKER_MAP) {
081            SharedBroker sharedBroker = SHARED_BROKER_MAP.get(config.getFilename());
082            if (sharedBroker != null) {
083                return sharedBroker.factory.getObject();
084            }
085        }
086        return null;
087    }
088
089    public Class getObjectType() {
090        return BrokerService.class;
091    }
092
093    public boolean isSingleton() {
094        return true;
095    }
096
097    public boolean isStart() {
098        return start;
099    }
100
101    public void setConfig(Resource config) {
102        this.config = config;
103    }
104
105    public void setStart(boolean start) {
106        this.start = start;
107    }
108
109}