1、订阅模式
解读:
1、1个生产者,1个交换机、多个队列、多个消费者
2、每一个消费者都有自己的一个队列
3、生产者没有将消息直接发送到队列,而是发送到了交换机
4、每个队列都要绑定到交换机
5、生产者发送的消息,经过交换机,到达队列,实现,一个消息被多个消费者获取的目的
注意:一个消费者队列可以有多个消费者实例,只有其中一个消费者实例会消费。
2、生产者
public class Send {
private final static String EXCHANGE_NAME = "test_exchange_fanout";
public static void main(String[] args) throws Exception {
Connection connection = ConnectionUtil.getConnection();
Channel channel = connection.createChannel();
channel.exchangeDeclare(EXCHANGE_NAME, "fanout");
for (int i = 0; i < 100; i++) {
String message = "Hello World" + String.valueOf(i);
channel.basicPublish(EXCHANGE_NAME, "", null, message.getBytes());
System.out.println(" [x] Sent '" + message + "'");
}
channel.close();
connection.close();
}
}
注意:消息发送到没有队列绑定的交换机时,消息将丢失,因为,交换机没有存储消息的能力,消息只能存在在队列中。
3、消费者一
public class Recv2 {
private final static String QUEUE_NAME = "test_queue_work1";
private final static String EXCHANGE_NAME = "test_exchange_fanout";
public static void main(String[] args) throws Exception {
Connection connection = ConnectionUtil.getConnection();
Channel channel = connection.createChannel();
channel.queueDeclare(QUEUE_NAME, false, false, false, null);
channel.queueBind(QUEUE_NAME, EXCHANGE_NAME, "");
channel.basicQos(1);
Consumer consumer = new DefaultConsumer(channel) {
@Override
public void handleDelivery(String consumerTag, Envelope envelope, AMQP.BasicProperties properties, byte[] body) throws IOException {
String message = new String(body, "UTF-8");
System.out.println("我是消费者一,我消费了:" + message);
try { TimeUnit.SECONDS.sleep(1); } catch (Exception e) { e.printStackTrace(); }
channel.basicAck(envelope.getDeliveryTag(),false);
}
};
channel.basicConsume(QUEUE_NAME, false, consumer);
}
}
4、消费者二
public class Recv {
private final static String QUEUE_NAME = "test_queue_work2";
private final static String EXCHANGE_NAME = "test_exchange_fanout";
public static void main(String[] args) throws Exception {
Connection connection = ConnectionUtil.getConnection();
Channel channel = connection.createChannel();
channel.queueDeclare(QUEUE_NAME, false, false, false, null);
channel.queueBind(QUEUE_NAME, EXCHANGE_NAME, "");
channel.basicQos(1);
Consumer consumer = new DefaultConsumer(channel) {
@Override
public void handleDelivery(String consumerTag, Envelope envelope, AMQP.BasicProperties properties, byte[] body) throws IOException {
String message = new String(body, "UTF-8");
System.out.println("我是消费者二,我消费了:" + message);
try { TimeUnit.SECONDS.sleep(1); } catch (Exception e) { e.printStackTrace(); }
channel.basicAck(envelope.getDeliveryTag(),false);
}
};
channel.basicConsume(QUEUE_NAME, false, consumer);
}
}
5、测试结果:
同一个消息被多个消费者获取。一个消费者队列可以有多个消费者实例,只有其中一个消费者实例会消费到消息。
在管理工具中查看队列和交换机的绑定关系: