Rabbitmq 简明教程

RabbitMQ - Publisher Application

现在，让我们创建一个将消息发送到 RabbitMQ Exchange 的发布程序应用程序。此交换将把消息传递给与交换绑定的队列。

Now let’s create a publisher application which will send message to the RabbitMQ Exchange. This exchange will deliver the message to the queue which is bound with the exchange.

Create Project

使用 Eclipse 选择 File → New * → *Maven Project 。勾选 创建简单项目（跳过原型选择），然后单击下一步。

Using eclipse, select File → New * → *Maven Project. Tick the *Create a simple project(skip archetype selection) * and click Next.

按照以下所示输入详细信息 −

Enter the details, as shown below −

  1. groupId − com.tutorialspoint

  2. artifactId − publisher

  3. version − 0.0.1-SNAPSHOT

  4. name − RabbitMQ Publisher

单击“完成”按钮，将创建新项目。

Click on Finish button and a new project will be created.

pom.xml

现在更新 pom.xml 的内容以包含 RabbitMQ 的依赖项。

Now update the content of pom.xml to include dependencies for RabbitMQ.

<project xmlns="http://maven.apache.org/POM/4.0.0" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
   xsi:schemaLocation="http://maven.apache.org/POM/4.0.0 https://maven.apache.org/xsd/maven-4.0.0.xsd">
   <modelVersion>4.0.0</modelVersion>
   <groupId>com.tutorialspoint.activemq</groupId>
   <artifactId>publisher</artifactId>
   <version>0.0.1-SNAPSHOT</version>
   <name>RabbitMQ Publisher</name>
   <properties>
      <java.version>11</java.version>
   </properties>
   <dependencies>
      <dependency>
         <groupId>com.rabbitmq</groupId>
         <artifactId>amqp-client</artifactId>
         <version>5.14.2</version>
      </dependency>
      <dependency>
         <groupId>org.slf4j</groupId>
         <artifactId>slf4j-api</artifactId>
         <version>1.7.26</version>
      </dependency>
      <dependency>
         <groupId>org.slf4j</groupId>
         <artifactId>slf4j-simple</artifactId>
         <version>1.7.26</version>
      </dependency>
   </dependencies>
</project>

现在创建一个将消息发送到 RabbitMQ 主题的发布程序类以将其广播到所有订阅者。

Now create a Publisher class which will send message to the RabbitMQ topic to broadcast it to all the subscribers.

package com.tutorialspoint.rabbitmq;

import java.io.IOException;
import java.util.Scanner;
import java.util.concurrent.TimeoutException;

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

public class Publisher {
   private static final String EXCHANGE = "MyExchange";
   public static void main(String[] args) throws IOException, TimeoutException {
      ConnectionFactory factory = new ConnectionFactory();
      factory.setHost("localhost");
      try (Connection connection = factory.newConnection();
      Channel channel = connection.createChannel()) {
         channel.exchangeDeclare(EXCHANGE, "fanout");
         Scanner input = new Scanner(System.in);
         String message;
         do {
            System.out.println("Enter message: ");
            message = input.nextLine();
            channel.basicPublish(EXCHANGE, "", null, message.getBytes());
         } while (!message.equalsIgnoreCase("Quit"));
      }
   }
}

生成程序类创建一个连接，创建一个通道，声明一个交换，然后要求用户输入消息。消息被发送到交换，并且作为队列名称，我们没有传递队列名称，因此所有与该交换绑定的队列都将收到该消息。如果用户输入退出，则应用程序终止，否则它会将消息发送到主题。

Producer class creates a connection, creates a channel, declare an exchange and then asks user to enter message. The message is sent to exchange and as queue name, we are not passing queue name thus all queues which are bound to this exchange will get the message. If user enters quit then application terminates else it will send the message to the topic.

我们将在 RabbitMQ - Test Application 一章中运行此应用程序。

We’ll run this application in RabbitMQ - Test Application chapter.