001/*
002 * Copyright 2002-2013 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.batch.integration.launch;
018
019import org.springframework.batch.core.JobExecution;
020import org.springframework.batch.core.JobExecutionException;
021import org.springframework.batch.core.launch.JobLauncher;
022import org.springframework.integration.handler.AbstractReplyProducingMessageHandler;
023import org.springframework.messaging.Message;
024import org.springframework.messaging.MessageHandlingException;
025import org.springframework.util.Assert;
026
027/**
028 * The {@link JobLaunchingGateway} is used to launch Batch Jobs. Internally it
029 * delegates to a {@link JobLaunchingMessageHandler}.
030 *
031 * @author Gunnar Hillert
032 *
033 * @since 1.3
034 */
035public class JobLaunchingGateway extends AbstractReplyProducingMessageHandler {
036
037        private final JobLaunchingMessageHandler jobLaunchingMessageHandler;
038
039        /**
040         * Constructor taking a {@link JobLauncher} as parameter.
041         *
042         * @param jobLauncher Must not be null.
043         *
044         */
045        public JobLaunchingGateway(JobLauncher jobLauncher) {
046                Assert.notNull(jobLauncher, "jobLauncher must not be null.");
047                this.jobLaunchingMessageHandler = new JobLaunchingMessageHandler(jobLauncher);
048        }
049
050        /**
051         * Launches a Batch Job using the provided request {@link Message}. The payload
052         * of the {@link Message} <em>must</em> be an instance of {@link JobLaunchRequest}.
053         *
054         * @param requestMessage must not be null.
055         * @return Generally a {@link JobExecution} will always be returned. An
056         * exception ({@link MessageHandlingException}) will only be thrown if there
057         * is a failure to start the job. The cause of the exception will be a
058         * {@link JobExecutionException}.
059         *
060         * @throws MessageHandlingException when a job cannot be launched
061         */
062        @Override
063        protected Object handleRequestMessage(Message<?> requestMessage) {
064
065                Assert.notNull(requestMessage, "The provided requestMessage must not be null.");
066
067                final Object payload = requestMessage.getPayload();
068
069                Assert.isInstanceOf(JobLaunchRequest.class, payload, "The payload must be of type JobLaunchRequest.");
070
071                final JobLaunchRequest jobLaunchRequest = (JobLaunchRequest) payload;
072
073                final JobExecution jobExecution;
074
075                try {
076                        jobExecution = this.jobLaunchingMessageHandler.launch(jobLaunchRequest);
077                } catch (JobExecutionException e) {
078                        throw new MessageHandlingException(requestMessage, e);
079                }
080
081                return jobExecution;
082
083        }
084
085}