Java sample code : การรับข้อมูลจากอุปกรณ์ IoT

private MqttClient client;

public IoTSubscriber() {
    try {
        // Create a new MQTT client with a unique client ID
        String clientId = MqttClient.generateClientId();
        client = new MqttClient("tcp://iot.eclipse.org:1883", clientId);

        // Set the callback object for handling incoming messages
        client.setCallback(this);

        // Connect to the MQTT broker
        client.connect();

        // Subscribe to the topic that the IoT device is publishing data to
        String topic = "iot/device/data";
        client.subscribe(topic);
    } catch (MqttException e) {
        e.printStackTrace();
    }
}

@Override
public void connectionLost(Throwable cause) {
    // Reconnect to the MQTT broker if the connection is lost
    System.out.println("Connection lost!");
    try {
        client.reconnect();
    } catch (MqttException e) {
        e.printStackTrace();
    }
}

@Override
public void messageArrived(String topic, MqttMessage message) throws Exception {
    // Handle the incoming message from the IoT device
    System.out.println("Received message: " + message.toString());
}

@Override
public void deliveryComplete(IMqttDeliveryToken token) {
    // Not used in this example
}

public static void main(String[] args) {
    // Create a new instance of the IoTSubscriber class
    IoTSubscriber subscriber = new IoTSubscriber();
}