es.devcircus.rabbitmq_examples.rabbitmq_rpc.RPCClient.java Source code

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Here is the source code for es.devcircus.rabbitmq_examples.rabbitmq_rpc.RPCClient.java

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/**
 * This file is part of rabbitmq-examples.
 *
 * rabbitmq-examples is free software; you can redistribute it and/or modify it
 * under the terms of the GNU General Public License as published by the Free
 * Software Foundation; either version 2, or (at your option) any later version.
 *
 * rabbitmq-examples is distributed in the hope that it will be useful, but
 * WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
 * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for more
 * details.
 *
 * You should have received a copy of the GNU General Public License along with
 * this program; see the file COPYING. If not, see
 * <http://www.gnu.org/licenses/>.
 */
package es.devcircus.rabbitmq_examples.rabbitmq_rpc;

import com.rabbitmq.client.ConnectionFactory;
import com.rabbitmq.client.Connection;
import com.rabbitmq.client.Channel;
import com.rabbitmq.client.QueueingConsumer;
import com.rabbitmq.client.AMQP.BasicProperties;
import java.util.UUID;

/**
 * @author Adrian Novegil Toledo
 * @mail adrian.novegil@gmail.com
 * @description
 */
public class RPCClient {

    private Connection connection;
    private Channel channel;
    private String requestQueueName = "rpc_queue";
    private String replyQueueName;
    private QueueingConsumer consumer;

    /**
     * 
     * @throws Exception 
     */
    public RPCClient() throws Exception {
        ConnectionFactory factory = new ConnectionFactory();
        //        factory.setHost("localhost");
        factory.setHost("192.168.0.202");
        connection = factory.newConnection();
        channel = connection.createChannel();

        replyQueueName = channel.queueDeclare().getQueue();
        consumer = new QueueingConsumer(channel);
        channel.basicConsume(replyQueueName, true, consumer);
    }

    /**
     * 
     * @param message
     * @return
     * @throws Exception 
     */
    public String call(String message) throws Exception {
        String response = null;
        String corrId = UUID.randomUUID().toString();

        BasicProperties props = new BasicProperties.Builder().correlationId(corrId).replyTo(replyQueueName).build();

        channel.basicPublish("", requestQueueName, props, message.getBytes());

        while (true) {
            QueueingConsumer.Delivery delivery = consumer.nextDelivery();
            if (delivery.getProperties().getCorrelationId().equals(corrId)) {
                response = new String(delivery.getBody(), "UTF-8");
                break;
            }
        }

        return response;
    }

    /**
     * 
     * @throws Exception 
     */
    public void close() throws Exception {
        connection.close();
    }

    /**
     * 
     * @param argv 
     */
    public static void main(String[] argv) {
        RPCClient fibonacciRpc = null;
        String response = null;
        try {
            fibonacciRpc = new RPCClient();

            System.out.println(" [x] Requesting fib(30)");
            response = fibonacciRpc.call("30");
            System.out.println(" [.] Got '" + response + "'");
        } catch (Exception e) {
        } finally {
            if (fibonacciRpc != null) {
                try {
                    fibonacciRpc.close();
                } catch (Exception ignore) {
                }
            }
        }
    }
}