szwlServer/src/main/java/com/szwl/service/base/MqttService.java

package com.szwl.service.base;

import lombok.extern.slf4j.Slf4j;
import org.eclipse.paho.client.mqttv3.MqttClient;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.stereotype.Service;

@Slf4j
@Service
public class MqttService {

    @Autowired
    private MqttClient mqttClient;

    /**
     * 发送消息
     * @param topic
     * @param message
     */
    public void sendMessage(String topic, String message, int qos) {
        try {
            mqttClient.publish(topic, message.getBytes(), qos, false);
        } catch (Exception e) {
            e.printStackTrace();
        }
    }

    /**
     * 订阅主题
     * @param topic
     * @param qos
     */
    public void subscribe(String topic, int qos) {
        try {
            mqttClient.subscribe(topic, qos);
        } catch (Exception e) {
            e.printStackTrace();
        }
    }

    /**
     * 取消订阅主题
     */
    public void unsubscribe(String topic) {
        try {
            mqttClient.unsubscribe(topic);
        } catch (Exception e) {
            e.printStackTrace();
        }
    }

}