RabbitMq 使用

记录rabbitmq的简单使用。其中记录了消息的确认与拒绝。

1.产生消息：

public void produce() {
    String queueName = "test";
    ConnectionFactory factory = new ConnectionFactory();
    factory.setHost("localhost");

    Connection con = null;
    Channel channel = null;
    try { 
        con = factory.newConnection();
        channel = con.createChannel();

        channel.queueDeclare(queueName, false, false, false, null);

        String msg = "hello rabbit2!";
        channel.basicPublish("", queueName, null, msg.getBytes());
        System.out.println("send msg ： " + msg);
    } catch (IOException e) {
        e.printStackTrace();
    } finally {
        close(channel)
    }
}    

2.消费消息：

public void consume() {
    String queueName = "test";

    ConnectionFactory factory = new ConnectionFactory();
    factory.setHost("localhost");

    Connection con = null;
    Channel channel = null;

    try {
        con = factory.newConnection();
        channel = con.createChannel();

        channel.queueDeclare(queueName, false, false, false, null);

        QueueingConsumer cons = new QueueingConsumer(channel);
        //RabbitMQ客户端接受消息最大数量;如果没有设置会一次消费所有消息
        channel.basicQos(0,1,false); 
        // 向channel中写入属性需要在一下这句程序之前才能起效
        // 当要设置一次消费的最大数量和消息回置时，需要将第二个参数设置为false--代表是否自动ack
        channel.basicConsume(queueName, false, cons);

        while (true) {
            Delivery deliver = cons.nextDelivery();
            String msg = new String(deliver.getBody());
//                if (msg.equals("hello")) {
//                    //拒绝消息（如果最后一个设置为true，此消息还会存在）
//                    channel.basicNack(deliver.getEnvelope().getDeliveryTag() , false, true);
//                }
//                //确认消息，已经收到  
//                else {
//                    channel.basicAck(deliver.getEnvelope().getDeliveryTag()  
//                            , false);  
//                }
            // 当autoAck为false时，就需要手动ack
            channel.basicAck(deliver.getEnvelope().getDeliveryTag(), false);  
            System.out.println("recive: " + msg);
        }

    } catch (IOException e) {
        e.printStackTrace();
    } catch (ShutdownSignalException e) {
        e.printStackTrace();
    } catch (ConsumerCancelledException e) {
        e.printStackTrace();
    } catch (InterruptedException e) {
        e.printStackTrace();
    } finally {
        close(channel);
    }
}

3.产生于消费公共方法，关闭链接：

private void close(Channel channel) {
    Connection connection = null;
    try {
        connection = channel.getConnection();
        channel.close();
    } catch (IOException e) {
        e.printStackTrace();
    }
    try {
        connection.close();
    } catch (IOException e) {
        e.printStackTrace();
    }
}