package com.zy.sc.common.mqtt; import org.eclipse.paho.client.mqttv3.MqttClient; import org.eclipse.paho.client.mqttv3.MqttConnectOptions; import org.eclipse.paho.client.mqttv3.persist.MemoryPersistence; import org.springframework.beans.factory.annotation.Autowired; import javax.annotation.PostConstruct; /** * Created by vincent on 2021/9/15 */ //@Component public class SubscribeSample { @Autowired private SubscribeListener subscribeListener; @PostConstruct public void init() { String HOST = "tcp://1.117.172.81:61613"; String TOPIC = "mytopic"; int qos = 1; String clientid = "subClient"; String userName = "admin"; String passWord = "password"; try { // host为主机名,test为clientid即连接MQTT的客户端ID,一般以客户端唯一标识符表示,MemoryPersistence设置clientid的保存形式,默认为以内存保存 MqttClient client = new MqttClient(HOST, clientid, new MemoryPersistence()); // MQTT的连接设置 MqttConnectOptions options = new MqttConnectOptions(); // 设置是否清空session,这里如果设置为false表示服务器会保留客户端的连接记录,这里设置为true表示每次连接到服务器都以新的身份连接 options.setCleanSession(true); // 设置连接的用户名 options.setUserName(userName); // 设置连接的密码 options.setPassword(passWord.toCharArray()); // 设置超时时间 单位为秒 options.setConnectionTimeout(10); // 设置会话心跳时间 单位为秒 服务器会每隔1.5*20秒的时间向客户端发送个消息判断客户端是否在线,但这个方法并没有重连的机制 options.setKeepAliveInterval(20); // 设置回调函数 client.setCallback(subscribeListener); client.connect(options); //订阅消息 client.subscribe(TOPIC, qos); } catch (Exception e) { e.printStackTrace(); } } }