RabbitMQ 之HelloWorld

引入

我们的HelloWorld程序将包含两个程序：一个可以发送消息的生产者和一个可以等待接受消息的消费者。

当然，我们的程序需要一些jar包，下载地址如下：

http://www.rabbitmq.com/java-client.html

程序

生产者

发送消息的流程如下图

我们的程序将会连接到RabbitMQServer，发送一个简单的消息，最后退出。

import com.rabbitmq.client.ConnectionFactory;import com.rabbitmq.client.Connection;import com.rabbitmq.client.Channel;public class Sender {private final static String QUEUE_NAME = "hello";  public static void main(String[] argv) throws Exception {          ConnectionFactory factory = new ConnectionFactory();    factory.setHost("localhost");    Connection connection = factory.newConnection();    Channel channel = connection.createChannel();    channel.queueDeclare(QUEUE_NAME, false, false, false, null);    String message = "Hello World!";    channel.basicPublish("", QUEUE_NAME, null, message.getBytes());    System.out.println(" [x] Sent '" + message + "'");    channel.close();    connection.close();  }}

消费者

接收方的流程如图：

接收方将一直监听消息并将其打印出来：

import com.rabbitmq.client.ConnectionFactory;import com.rabbitmq.client.Connection;import com.rabbitmq.client.Channel;import com.rabbitmq.client.QueueingConsumer;public class Received {    private final static String QUEUE_NAME = "hello";    public static void main(String[] argv) throws Exception {    ConnectionFactory factory = new ConnectionFactory();    factory.setHost("localhost");    Connection connection = factory.newConnection();    Channel channel = connection.createChannel();    channel.queueDeclare(QUEUE_NAME, false, false, false, null);    System.out.println(" [*] Waiting for messages. To exit press CTRL+C");        QueueingConsumer consumer = new QueueingConsumer(channel);    channel.basicConsume(QUEUE_NAME, true, consumer);        while (true) {      QueueingConsumer.Delivery delivery = consumer.nextDelivery();      String message = new String(delivery.getBody());      System.out.println(" [x] Received '" + message + "'");    }  }}

首先我们运行Sender.java,然后是Received.java。结果如下：

 [*] Waiting for messages. To exit press CTRL+C
 [x] Received 'Hello World!'

在运行之前，要确保服务已经启动，打开rabbit 命令窗口，输入：rabbitmq-server start 来启动它。

当我们“生产”了一个消息后，可以使用“rabbitmqctl list_queues” 来查看队列。