java - 我如何将带有用户名和密码的 Java mqtt 客户端连接到 emqttd(EMQ) 代理？

Question

我可以使用此 Java 代码订阅 mosquitto 代理，无需用户名和密码。现在，我想订阅一个需要一些虚拟用户名和密码的 emqttd 代理。我怎样才能做到这一点？。谢谢。

http://tgrall.github.io/blog/2017/01/02/getting-started-with-mqtt/#disqus_thread

https://github.com/emqtt/emqttd

package com.mapr.demo.mqtt.simple;

import org.eclipse.paho.client.mqttv3.MqttClient;
import org.eclipse.paho.client.mqttv3.MqttException;

public class Subscriber {

  public static void main(String[] args) throws MqttException {

    System.out.println("== START SUBSCRIBER ==");

    MqttClient client=new MqttClient("tcp://localhost:1883", MqttClient.generateClientId());
    client.setCallback( new SimpleMqttCallBack() );
    client.connect();

    client.subscribe("iot_data");

  }

}

Answer 1

您可以使用 MqttConnectOptions :

 public class Subscriber {

    private static final String CONNECTION_URL = "tcp://localhost:1883";
    private static final String SUBSCRIPTION = "iot_data";
    private static final String USERNAME = "username";
    private static final String PASSWORD = "top-secret";


    public static void main(String[] args) throws MqttException {

       System.out.println("== START SUBSCRIBER ==");

       MqttClient client = new MqttClient(CONNECTION_URL, 
       MqttClient.generateClientId());

       MqttConnectOptions connOpts = setUpConnectionOptions(USERNAME, PASSWORD);
       client.connect(connOpts);

       client.subscribe(SUBSCRIPTION);

    }

   private static MqttConnectOptions setUpConnectionOptions(String username, String password) {
       MqttConnectOptions connOpts = new MqttConnectOptions();
       connOpts.setCleanSession(true);
       connOpts.setUserName(username);
       connOpts.setPassword(password.toCharArray());
       return connOpts;
   }  

  }