Paho java client failing to connect: Bad user name or password (4)

Question

Is there some issue with paho java client when connect with username & password ??

From paho JS client it works but from java client it doesn't. I have this code

MqttConnectOptions conOpt = new MqttConnectOptions();
conOpt.setCleanSession(false);
conOpt.setUserName("test5");
conOpt.setPassword("123".toCharArray());
MqttDefaultFilePersistence filePersistence = new MqttDefaultFilePersistence("/home/manish/Downloads/mqttPersist");
client = new MqttAsyncClient(appProps.getProperty("mqtt.broker"),
        appProps.getProperty("mqtt.clientId"), filePersistence);
client.setCallback(this);
client.connect(conOpt, new IMqttActionListener() {
    @Override
    public void onSuccess(IMqttToken imt) {
        try {
            client.subscribe(Constants.INTERNAL_TOPICS, Constants.INTERNAL_TOPIC_QOS);
        } catch (MqttException ex) {
            ex.printStackTrace();
        }
    }

    @Override
    public void onFailure(IMqttToken imt, Throwable thrwbl) {
        thrwbl.printStackTrace();
    }
});

i am getting this exception

Bad user name or password (4)
at org.eclipse.paho.client.mqttv3.internal.ExceptionHelper.createMqttException(ExceptionHelper.java:28)
at org.eclipse.paho.client.mqttv3.internal.ClientState.notifyReceivedAck(ClientState.java:885)
at org.eclipse.paho.client.mqttv3.internal.CommsReceiver.run(CommsReceiver.java:118)
at java.lang.Thread.run(Thread.java:745)
emqt console

06:47:36.456 [error] Client(notification_subs_bot@127.0.0.1:50741): Username 'undefined' login failed for username_or_password_undefined
06:47:36.463 [error] Client(notification_subs_bot@127.0.0.1:50742): Username 'undefined' login failed for username_or_password_undefined

According paho documentation public void setPassword(char[] password) So here i am passing char[] as paasword

I am using emqttd broker

Answer 1

here is a code that publish to a mqtt broker using eclipse paho mqtt library.

import com.fasterxml.jackson.core.JsonProcessingException;
import org.eclipse.paho.client.mqttv3.*;
import org.eclipse.paho.client.mqttv3.persist.MemoryPersistence;
import com.fasterxml.jackson.databind.JsonNode;
import com.fasterxml.jackson.databind.ObjectMapper;

import java.io.IOException;
import java.nio.charset.StandardCharsets;

public class GpsPublish {

    public static void main(String[] args) {


        String uri = "tcp://000.000.000.000:1883";
        String deviceName = "SENSE2";
        String deviceToken = "IHAUD6kvW6C1Zp10uJm4";
        String topic = "v1/devices/me/telemetry";
        String clientId = MqttAsyncClient.generateClientId();
        MqttClientPersistence persistence = new MemoryPersistence();

        ObjectMapper MAPPER = new ObjectMapper();
        String jsonString = "{\"latitude\":51.520008, \"longitude\":13.304954, \"temperature\":31.5, \"active\": false}";

        try {
            MqttAsyncClient client = new MqttAsyncClient(uri, clientId, persistence);
            MqttConnectOptions options = new MqttConnectOptions();
            options.setUserName(deviceToken);


            client.connect(options, null, new IMqttActionListener() {
                @Override
                public void onSuccess(IMqttToken iMqttToken) {
                    System.out.println("[{" + deviceName + "}] connected to Thingsboard!");
                }

                @Override
                public void onFailure(IMqttToken iMqttToken, Throwable e) {
                    System.out.println("[{" + deviceName + "}] failed to connect to Thingsboard!");
                    // System.out.println("reason " + e.getReasonCode());
                    System.out.println("msg " + e.getMessage());
                    System.out.println("loc " + e.getLocalizedMessage());
                    System.out.println("cause " + e.getCause());
                    System.out.println("excep " + e);
                    e.printStackTrace();
                }
            }).waitForCompletion();

            JsonNode data = MAPPER.readTree(jsonString);
            MqttMessage msg = new MqttMessage(MAPPER.writeValueAsString(data).getBytes(StandardCharsets.UTF_8));

            IMqttDeliveryToken deliveryToken = client.publish(topic, msg, null, new IMqttActionListener() {
                @Override
                public void onSuccess(IMqttToken asyncActionToken) {
                    System.out.println("Data updated!");
                }

                @Override
                public void onFailure(IMqttToken asyncActionToken, Throwable exception) {
                    System.out.println("[{" + deviceName + "}] Data update failed!");
                    System.out.println(exception.getMessage());
                }
            });
            deliveryToken.waitForCompletion();
            System.out.println("[{" + deviceName + "}] delivery completed at Thingsboard!");

            client.disconnect().waitForCompletion();
            System.out.println("[{" + deviceName + "}] disconnected to Thingsboard!");
        } catch (MqttException e) {
            System.out.println("Failed to connect to the server: " + e);
        } catch (JsonProcessingException e) {
            e.printStackTrace();
        } catch (IOException e) {
            e.printStackTrace();
        }
    }
}

Answer 2

Is there some issue with paho java client when connect with username & password ??

nop. there is not, it looks like your user name and password is not in the CAL of the broker, you need to verify that your credentials for the Authentication are ok.

and that the broker has the ACL right