When i run my code it's working fine but after some hours it stop working and show this errorNot able to publish: MQTT client is not connected publicMqtt5AsyncClientconnect(String host,intport){Mqtt5AsyncClientclient=MqttClient.builder().useMqttVersion5() .identifier(UUID.randomUUID()....
最后,我们需要检查连接状态,以确保客户端已成功连接到 MQTT 服务器。以下是检查连接状态的代码示例: publicvoidcheckConnection(){try{if(client.isConnected()){System.out.println("Connected to MQTT server");}else{System.out.println("Not connected to MQTT server");}}catch(MqttExceptionme){me.printStackT...
System.out.println("mqttClient is not connect"); } }else { System.out.println("mqttClient is null"); } } //重新连接MQTT服务器 public void reConnect() { if(null != mqttClient) { if(!mqttClient.isConnected()) { if(null != mqttConnectOptions) { try { mqttClient.connect(mqttConnect...
client = connect_mqtt() # 返回一个链接:使用函数on_connect(client, userdata, flags, rc)链接服务器,client.connect(broker, port) client.loop_start() publish(client)# 发送消息:client.publish(topic_publish, **, qos=2, retain=False) 1. 2. 3. 一部分是请求的接受并处理 client.on_message=on_...
3.(方法一)MqttClient.java文件 importlombok.extern.slf4j.Slf4j;importorg.eclipse.paho.client.mqttv3.MqttConnectOptions;importorg.eclipse.paho.client.mqttv3.MqttDeliveryToken;importorg.eclipse.paho.client.mqttv3.MqttException;importorg.eclipse.paho.client.mqttv3.MqttMessage;importorg.eclipse.paho.client...
isConnected =false;if(!mMqttClient.isConnected()){ subscribeMqttTopic(); } } }; registerReceiver(receiver, intentFilter); subscribeMqttTopic(); }privatevoidsubscribeMqttTopic(){ subscriberThread =newThread(newRunnable() {publicvoidrun(){do{try{ ...
Java Paho MQTT是一个开源的MQTT客户端库,用于在Java应用程序中实现MQTT协议的通信。它提供了订阅和发布消息的功能,使得应用程序能够与MQTT代理进行通信。 在使用Java Paho MQTT订阅时,如果遇到无法重新连接的问题,可能是由于以下原因导致的: 网络连接问题:检查网络连接是否正常,确保能够与MQTT代理建立连接。可以尝试使用...
http://log.info("接收消息回调: 接收消息内容 : " + new String(mqttMessage.getPayload()));*/ } 已经设置了自动重连功能 options.setAutomaticReconnect(true); 在进行重连时过了几秒就报错 已断开连接 (32109) - java.io.EOFException atorg.eclipse.paho.client.mqttv3.internal.CommsReceiver.run(CommsRec...
if( mqttClient.isConnected() ) { return true; } } catch (MqttException e) { e.printStackTrace(); } catch (InterruptedException e) { e.printStackTrace(); } return false; } /** * 客户端连接 * @return */ public void connect(){ ...
等待来自服务器的响应时超时 (32000) at org.eclipse.paho.client.mqttv3.internal 前言 本文主要针对MQTT的概念、安装、基础使用、常见报错问题做总结。 概念 MQTT是什么 消息队列遥测传输,是ISO标准下基于发布/订阅范式的消息协议; 工作在TCP/IP协议族上,是为了硬件性能低下的远程设备以及网络状况糟糕的情况下而设...