biz.fstechnology.micro.server.jms.AbstractJmsService.java Source code

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Here is the source code for biz.fstechnology.micro.server.jms.AbstractJmsService.java

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/*
 * @(#) biz.fstechnology.micro.server.jms.AbstractJmsService
 * Copyright (c) 2016 4S Technology
 *
 * 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 biz.fstechnology.micro.server.jms;

import java.util.concurrent.ExecutionException;
import java.util.concurrent.ExecutorService;
import java.util.concurrent.Executors;
import java.util.concurrent.Future;

import javax.jms.Connection;
import javax.jms.ConnectionFactory;
import javax.jms.DeliveryMode;
import javax.jms.JMSException;
import javax.jms.Message;
import javax.jms.MessageConsumer;
import javax.jms.MessageListener;
import javax.jms.MessageProducer;
import javax.jms.ObjectMessage;
import javax.jms.Session;

import org.springframework.jms.JmsException;
import org.springframework.jms.core.JmsTemplate;

import biz.fstechnology.micro.common.Request;
import biz.fstechnology.micro.common.Result;
import biz.fstechnology.micro.server.AbstractService;

/**
 * TODO Type Description
 * 
 * @author Maruyama Takayuki
 * @since 2016/01/01
 */
public abstract class AbstractJmsService extends AbstractService implements MessageListener {

    protected abstract String getBrokerUrl();

    protected abstract String getClientIdPrefix();

    protected abstract ConnectionFactory getConnectionFactory();

    protected abstract String getListenTopic();

    private MessageProducer replyProducer;

    private Session session;

    protected final JmsTemplate createJmsTemplate() {
        JmsTemplate jmsTemplate = new JmsTemplate(getConnectionFactory());
        jmsTemplate.setPubSubDomain(true);
        return jmsTemplate;
    }

    /**
     * @see biz.fstechnology.micro.server.Service#init()
     */
    @Override
    public void init() throws Exception {
        Connection connection = createJmsTemplate().getConnectionFactory().createConnection();
        session = connection.createSession(false, Session.AUTO_ACKNOWLEDGE);
        MessageConsumer consumer = session.createConsumer(session.createTopic(getListenTopic()));
        consumer.setMessageListener(this);

        replyProducer = session.createProducer(null);
        replyProducer.setDeliveryMode(DeliveryMode.NON_PERSISTENT);

        connection.start();
    }

    /**
     * @see javax.jms.MessageListener#onMessage(javax.jms.Message)
     */
    @Override
    public void onMessage(Message message) {
        try {
            ExecutorService executor = Executors.newSingleThreadExecutor();

            if (((ObjectMessage) message).getObject() instanceof Result) {
                // no op
                return;
            }
            Request<?> request = (Request<?>) ((ObjectMessage) message).getObject(); // cast hell...
            Future<Request<?>> preProcessFuture = executor.submit(() -> onPreProcessRequest(request));

            Future<Result<?>> resultFuture = executor.submit(() -> processRequest(preProcessFuture.get()));

            Future<Result<?>> postProcessFuture = executor
                    .submit(() -> onPostProcessRequest(request, resultFuture.get()));
            executor.shutdown();

            Result<?> result = postProcessFuture.get();

            ResponseMessageCreator messageCreator = new ResponseMessageCreator();
            messageCreator.setContents(result);
            messageCreator.setRequestId(message.getJMSCorrelationID());

            replyProducer.send(message.getJMSReplyTo(), messageCreator.createMessage(session));

        } catch (JMSException | InterruptedException | ExecutionException e) {
            // TODO Auto-generated catch block
            e.printStackTrace();
            Result<Object> result = new Result<>(e);
            try {
                ResponseMessageCreator messageCreator = new ResponseMessageCreator();
                messageCreator.setContents(result);
                messageCreator.setRequestId(message.getJMSCorrelationID());

                replyProducer.send(message.getJMSReplyTo(), messageCreator.createMessage(session));
            } catch (JmsException | JMSException e1) {
                e1.printStackTrace();
            }
        }
    }

    /**
     * @see biz.fstechnology.micro.server.Service#onPostProcessRequest(biz.fstechnology.micro.common.Request,
     * biz.fstechnology.micro.common.Result)
     */
    @Override
    public <T, U> Result<U> onPostProcessRequest(Request<T> request, Result<U> result) {
        return result;
    }

}