RabbitMQ sample code (1)

1. Basic queue message sending and receiving

Simple model, using the default exchange, sending to the specified queue, one-to-one sending and receiving.
Sender-->(Default Exchange)-->Queue-->Receiver

(1) Send the specified queue message
import java.io.IOException;
import java.util.concurrent.TimeoutException;

import com.rabbitmq.client.Channel;
import com.rabbitmq.client.Connection;
import com.rabbitmq.client.ConnectionFactory;

public class SendDemo {
    private final static String QUEUE_NAME = "hello";

    public static void main(String[] argv) {
        ConnectionFactory factory = new ConnectionFactory();
        factory.setHost("localhost");
        Connection connection = null;
        try {
            connection = factory.newConnection();
            Channel channel = connection.createChannel();
            // 定义非持久queue
            channel.queueDeclare(QUEUE_NAME, false, false, false, null);
            String message = "Hello World!";
            // 发送消息到默认exchange，指定queue
            channel.basicPublish("", QUEUE_NAME, null, message.getBytes("UTF-8"));
            System.out.println(" [x] Sent '" + message + "'");
            channel.close();
            connection.close();
        } catch (IOException e) {
            e.printStackTrace();
        } catch (TimeoutException e) {
            e.printStackTrace();
        }
    }
}

(2) Consumption of messages through pull mode (not recommended)
import java.io.IOException;
import java.util.concurrent.TimeoutException;

import com.rabbitmq.client.Channel;
import com.rabbitmq.client.Connection;
import com.rabbitmq.client.ConnectionFactory;
import com.rabbitmq.client.GetResponse;

/**
 * Consumption of messages through pull mode (not recommended)
 * 
 * @date March 8, 2019 3:31:14 PM
 */
public class RecvPull {     private final static String QUEUE_NAME = "hello";

    public static void main(String[] argv) {
        ConnectionFactory factory = new ConnectionFactory();
        factory.setHost("localhost");
        Connection connection = null;
        try {
            connection = factory.newConnection();
            Channel channel = connection.createChannel();
            // 定义非持久queue
            channel.queueDeclare(QUEUE_NAME, false, false, false, null);
            System.out.println(" [*] Waiting for messages. To exit press CTRL+C");
            // 开始消费指定queue的消息
            while (true) {
                try {
                    Thread.sleep(3000);
                } catch (InterruptedException e) {
                    e.printStackTrace();
                }
                GetResponse response = channel.basicGet(QUEUE_NAME, true);
                if (response == null) {
                    continue;
                }
                String responseStr = new String(response.getBody());
                System.out.println("responseStr: " + responseStr);
            }
        } catch (IOException e) {
            e.printStackTrace();
        } catch (TimeoutException e) {
            e.printStackTrace();
        }
    }
}

(3) Consume messages through push mode (recommended)
import java.io.IOException;
import java.util.concurrent.TimeoutException;

import com.rabbitmq.client.AMQP;
import com.rabbitmq.client.Channel;
import com.rabbitmq.client.Connection;
import com.rabbitmq.client.ConnectionFactory;
import com.rabbitmq.client.Consumer;
import com.rabbitmq.client.DefaultConsumer;
import com.rabbitmq.client.Envelope;

/**
 * Consumption of messages via push mode (recommended)
 * 
 * @date March 8, 2019 3:31:56 PM
 */
public class RecvPush {     private final static String QUEUE_NAME = "hello";

    public static void main(String[] argv) {
        ConnectionFactory factory = new ConnectionFactory();
        factory.setHost("localhost");
        Connection connection = null;
        try {
            connection = factory.newConnection();
            Channel channel = connection.createChannel();
            // 定义非持久queue
            channel.queueDeclare(QUEUE_NAME, false, false, false, null);
            System.out.println(" [*] Waiting for messages. To exit press CTRL+C");
            // 定义监听消费者
            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(" [x] Received '" + message + "'");
                }
            };
            // 开始消费指定queue的消息
            channel.basicConsume(QUEUE_NAME, true, consumer);

        } catch (IOException e) {
            e.printStackTrace();
        } catch (TimeoutException e) {
            e.printStackTrace();
        }
    }
}