001/*
002 * Copyright 2002-2012 the original author or authors.
003 *
004 * Licensed under the Apache License, Version 2.0 (the "License");
005 * you may not use this file except in compliance with the License.
006 * You may obtain a copy of the License at
007 *
008 *      https://www.apache.org/licenses/LICENSE-2.0
009 *
010 * Unless required by applicable law or agreed to in writing, software
011 * distributed under the License is distributed on an "AS IS" BASIS,
012 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
013 * See the License for the specific language governing permissions and
014 * limitations under the License.
015 */
016
017package org.springframework.jms.core.support;
018
019import javax.jms.ConnectionFactory;
020
021import org.apache.commons.logging.Log;
022import org.apache.commons.logging.LogFactory;
023
024import org.springframework.beans.factory.BeanInitializationException;
025import org.springframework.beans.factory.InitializingBean;
026import org.springframework.jms.core.JmsTemplate;
027
028/**
029 * Convenient super class for application classes that need JMS access.
030 *
031 * <p>Requires a ConnectionFactory or a JmsTemplate instance to be set.
032 * It will create its own JmsTemplate if a ConnectionFactory is passed in.
033 * A custom JmsTemplate instance can be created for a given ConnectionFactory
034 * through overriding the {@link #createJmsTemplate} method.
035 *
036 * @author Mark Pollack
037 * @since 1.1.1
038 * @see #setConnectionFactory
039 * @see #setJmsTemplate
040 * @see #createJmsTemplate
041 * @see org.springframework.jms.core.JmsTemplate
042 */
043public abstract class JmsGatewaySupport implements InitializingBean {
044
045        /** Logger available to subclasses */
046        protected final Log logger = LogFactory.getLog(getClass());
047
048        private JmsTemplate jmsTemplate;
049
050
051        /**
052         * Set the JMS connection factory to be used by the gateway.
053         * Will automatically create a JmsTemplate for the given ConnectionFactory.
054         * @see #createJmsTemplate
055         * @see #setConnectionFactory(javax.jms.ConnectionFactory)
056         */
057        public final void setConnectionFactory(ConnectionFactory connectionFactory) {
058                this.jmsTemplate = createJmsTemplate(connectionFactory);
059        }
060
061        /**
062         * Create a JmsTemplate for the given ConnectionFactory.
063         * Only invoked if populating the gateway with a ConnectionFactory reference.
064         * <p>Can be overridden in subclasses to provide a JmsTemplate instance with
065         * a different configuration.
066         * @param connectionFactory the JMS ConnectionFactory to create a JmsTemplate for
067         * @return the new JmsTemplate instance
068         * @see #setConnectionFactory
069         */
070        protected JmsTemplate createJmsTemplate(ConnectionFactory connectionFactory) {
071                return new JmsTemplate(connectionFactory);
072        }
073
074        /**
075         * Return the JMS ConnectionFactory used by the gateway.
076         */
077        public final ConnectionFactory getConnectionFactory() {
078                return (this.jmsTemplate != null ? this.jmsTemplate.getConnectionFactory() : null);
079        }
080
081        /**
082         * Set the JmsTemplate for the gateway.
083         * @see #setConnectionFactory(javax.jms.ConnectionFactory)
084         */
085        public final void setJmsTemplate(JmsTemplate jmsTemplate) {
086                this.jmsTemplate = jmsTemplate;
087        }
088
089        /**
090         * Return the JmsTemplate for the gateway.
091         */
092        public final JmsTemplate getJmsTemplate() {
093                return this.jmsTemplate;
094        }
095
096        @Override
097        public final void afterPropertiesSet() throws IllegalArgumentException, BeanInitializationException {
098                if (this.jmsTemplate == null) {
099                        throw new IllegalArgumentException("'connectionFactory' or 'jmsTemplate' is required");
100                }
101                try {
102                        initGateway();
103                }
104                catch (Exception ex) {
105                        throw new BeanInitializationException("Initialization of JMS gateway failed: " + ex.getMessage(), ex);
106                }
107        }
108
109        /**
110         * Subclasses can override this for custom initialization behavior.
111         * Gets called after population of this instance's bean properties.
112         * @throws java.lang.Exception if initialization fails
113         */
114        protected void initGateway() throws Exception {
115        }
116
117}