/** *  * Copyright 2005 LogicBlaze, Inc. http://www.logicblaze.com *  * Licensed under the Apache License, Version 2.0 (the "License");  * you may not use this file except in compliance with the License.  * You may obtain a copy of the License at  *  * http://www.apache.org/licenses/LICENSE-2.0 *  * Unless required by applicable law or agreed to in writing, software * distributed under the License is distributed on an "AS IS" BASIS,  * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.  * See the License for the specific language governing permissions and  * limitations under the License.  *  **/package org.jencks;import org.springframework.beans.factory.InitializingBean;import javax.jms.MessageListener;import javax.resource.spi.UnavailableException;/** * An implementation of {@link javax.resource.spi.endpoint.MessageEndpointFactory} which always * uses a single shared instance of a {@link javax.jms.MessageListener} for every endpoint, irrespective * of how many physical endpoints are used. * * @version $Revision: 1.1.1.1 $ */public class SingletonEndpointFactory extends EndpointFactorySupport implements InitializingBean {    private MessageListener messageListener;    public SingletonEndpointFactory() {    }    public SingletonEndpointFactory(MessageListener messageListener) {        this.messageListener = messageListener;    }    public void afterPropertiesSet() throws Exception {        if (messageListener == null) {            throw new IllegalArgumentException("messageListener property must be set");        }    }    public MessageListener getMessageListener() {        return messageListener;    }    public void setMessageListener(MessageListener messageListener) {        this.messageListener = messageListener;    }    // Implementation methods    //-------------------------------------------------------------------------    protected MessageListener createMessageListener() throws UnavailableException {        return messageListener;    }}