先下载MQTTX: MQTTX: Your All-in-one MQTT Client Toolbox

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打开MQTTX，创建连接，点击NEW SUBSCRIPTION,创建一个主题，这里使用test/topic,在下面Json中填写配置好的主题，点击发送测试OK。订阅者，建立一个主题：

package com.jasonhong.application.media.mq.mqtt;

import org.eclipse.paho.client.mqttv3.IMqttDeliveryToken;
import org.eclipse.paho.client.mqttv3.MqttCallback;  
import org.eclipse.paho.client.mqttv3.MqttClient;  
import org.eclipse.paho.client.mqttv3.MqttConnectOptions;  
import org.eclipse.paho.client.mqttv3.MqttException;