我正在开发 Eclipse 中的 MQTT 应用程序。我之前使用 mqtt-dashboard 作为公共代理,并且能够看到我在仪表板上发布的消息。由于某种原因,这个网站已经关闭,所以我切换到 mosquitto。我的代码是相同的,但我仍然无法向该代理发布消息。我的代码如下:
public static void main(String[] args) {
String topic = "home automation systems";
String content = "I am a test message";
int qos = 2;
String broker = "tcp://test.mosquitto.org:1883";
String clientId = "home automation";
MemoryPersistence persistence = new MemoryPersistence();
try {
MqttClient sampleClient = new MqttClient(broker, clientId, persistence);
MqttConnectOptions connOpts = new MqttConnectOptions();
connOpts.setCleanSession(true);
System.out.println("Connecting to broker: "+broker);
sampleClient.connect(connOpts);
System.out.println("Connected");
System.out.println("Publishing message: "+content);
MqttMessage message = new MqttMessage(content.getBytes());
message.setQos(qos);
sampleClient.publish(topic, message);
System.out.println("Message published");
sampleClient.disconnect();
System.out.println("Disconnected");
System.exit(0);
}
catch(MqttException me) {
System.out.println("reason "+me.getReasonCode());
System.out.println("msg "+me.getMessage());
System.out.println("loc "+me.getLocalizedMessage());
System.out.println("cause "+me.getCause());
System.out.println("excep "+me);
me.printStackTrace();
}
}
}
我正在尝试在此仪表板上查看已发布的消息:http: //test-mosquitto.herokuapp.com/ 但看不到我的消息。如果我遗漏了什么,请纠正我。我是新手。谢谢。