java - 无法连接到 Android 上的 MQTT 服务器

Question

我正在尝试编写一个简单的代码来发布和订阅 Android Java 上的 MQTT 服务器。当我的应用程序尝试运行 onCreat() 时，它一直在崩溃。我在互联网上尝试了很多解决方案，但我无法弄清楚并解决这个问题，请帮助。

这是我的代码和错误日志：

这是我的 MainActivity.java

import androidx.annotation.NonNull;
import androidx.appcompat.app.AppCompatActivity;
import org.eclipse.paho.android.service.MqttAndroidClient;
import org.eclipse.paho.client.mqttv3.DisconnectedBufferOptions;
import org.eclipse.paho.client.mqttv3.IMqttActionListener;
import org.eclipse.paho.client.mqttv3.IMqttToken;
import org.eclipse.paho.client.mqttv3.MqttConnectOptions;
import org.eclipse.paho.client.mqttv3.MqttException;
import org.eclipse.paho.client.mqttv3.MqttMessage;
import java.io.UnsupportedEncodingException;

import android.content.Context;
import android.os.Bundle;
import android.util.Log;

public class MainActivity extends AppCompatActivity {

    private MqttAndroidClient mqttAndroidClient;
    private static final String TAG = "PahoMqttClient";

    @Override
    protected void onCreate ( Bundle savedInstanceState ) {
        super.onCreate ( savedInstanceState );
        setContentView ( R.layout.activity_main );
        getMqttClient ( getApplicationContext(),"tcp//test.mosquitto.org:1883","esp32_hello" );
    }

    public MqttAndroidClient getMqttClient( Context context, String brokerUrl, String clientId) {
        mqttAndroidClient = new MqttAndroidClient(context, brokerUrl, clientId);
        try {
            IMqttToken token = mqttAndroidClient.connect(getMqttConnectionOption());
            token.setActionCallback(new IMqttActionListener() {
                @Override
                public void onSuccess(IMqttToken asyncActionToken) {
                    mqttAndroidClient.setBufferOpts(getDisconnectedBufferOptions());
                    Log.d( "TAG", "Success");
                }
                @Override
                public void onFailure(IMqttToken asyncActionToken, Throwable exception) {
                    Log.d("TAG", "Failure " + exception.toString());
                }
            });
        } catch (MqttException e) {
            e.printStackTrace();
        }
        return mqttAndroidClient;
    }
    public void disconnect(@NonNull MqttAndroidClient client) throws MqttException {
        IMqttToken mqttToken = client.disconnect();
        mqttToken.setActionCallback(new IMqttActionListener() {
            @Override
            public void onSuccess(IMqttToken iMqttToken) {
                Log.d(TAG, "Successfully disconnected");
            }

            @Override
            public void onFailure(IMqttToken iMqttToken, Throwable throwable) {
                Log.d(TAG, "Failed to disconnected " + throwable.toString());
            }
        });
    }

    @NonNull
    private DisconnectedBufferOptions getDisconnectedBufferOptions() {
        DisconnectedBufferOptions disconnectedBufferOptions = new DisconnectedBufferOptions();
        disconnectedBufferOptions.setBufferEnabled(true);
        disconnectedBufferOptions.setBufferSize(100);
        disconnectedBufferOptions.setPersistBuffer(false);
        disconnectedBufferOptions.setDeleteOldestMessages(false);
        return disconnectedBufferOptions;
    }

    @NonNull
    private MqttConnectOptions getMqttConnectionOption() {
        MqttConnectOptions mqttConnectOptions = new MqttConnectOptions();
        mqttConnectOptions.setCleanSession(false);
        mqttConnectOptions.setAutomaticReconnect(true);
        //mqttConnectOptions.setWill(Constants.PUBLISH_TOPIC, "I am going offline".getBytes(), 1, true);
        //mqttConnectOptions.setUserName("ngbllzzy");
        //mqttConnectOptions.setPassword("WtjhZKl3OPoK".toCharArray());
        return mqttConnectOptions;
    }
/*

    public void publishMessage(@NonNull MqttAndroidClient client, @NonNull String msg, int qos, @NonNull String topic)
            throws MqttException, UnsupportedEncodingException {
        byte[] encodedPayload = new byte[0];
        encodedPayload = msg.getBytes("UTF-8");
        MqttMessage message = new MqttMessage(encodedPayload);
        message.setId(320);
        message.setRetained(true);
        message.setQos(qos);
        client.publish(topic, message);
    }

    public void subscribe(@NonNull MqttAndroidClient client, @NonNull final String topic, int qos) throws MqttException {
        IMqttToken token = client.subscribe(topic, qos);
        token.setActionCallback(new IMqttActionListener() {
            @Override
            public void onSuccess(IMqttToken iMqttToken) {
                Log.d(TAG, "Subscribe Successfully " + topic);
            }

            @Override
            public void onFailure(IMqttToken iMqttToken, Throwable throwable) {
                Log.e(TAG, "Subscribe Failed " + topic);

            }
        });
    }

    public void unSubscribe(@NonNull MqttAndroidClient client, @NonNull final String topic) throws MqttException {

        IMqttToken token = client.unsubscribe(topic);

        token.setActionCallback(new IMqttActionListener() {
            @Override
            public void onSuccess(IMqttToken iMqttToken) {
                Log.d(TAG, "UnSubscribe Successfully " + topic);
            }

            @Override
            public void onFailure(IMqttToken iMqttToken, Throwable throwable) {
                Log.e(TAG, "UnSubscribe Failed " + topic);
            }
        });
    }

 */

}

我使用这些权限AndroidMainfest

<uses-permission android:name="android.permission.WAKE_LOCK" />
<uses-permission android:name="android.permission.INTERNET" />
<uses-permission android:name="android.permission.WRITE_EXTERNAL_STORAGE" />
<uses-permission android:name="android.permission.ACCESS_NETWORK_STATE" />
<uses-permission android:name="android.permission.READ_PHONE_STATE" />
<uses-permission android:name="android.permission.READ_EXTERNAL_STORAGE" />

我<service android:name="org.eclipse.paho.android.service.MqttService"/>也加了这个。

我也在我的build.gradle(:app)中使用这些实现

implementation 'org.eclipse.paho:org.eclipse.paho.client.mqttv3:1.1.1'
implementation 'org.eclipse.paho:org.eclipse.paho.client.mqttv3:1.1.1'
implementation 'org.eclipse.paho:org.eclipse.paho.android.service:1.1.1'

这是我的错误日志：

E/AndroidRuntime: FATAL EXCEPTION: main
    Process: com.example.im_tierd_of_this_shit, PID: 28422
    java.lang.NoClassDefFoundError: Failed resolution of: Landroid/support/v4/content/LocalBroadcastManager;
        at org.eclipse.paho.android.service.MqttAndroidClient.registerReceiver(MqttAndroidClient.java:450)
        at org.eclipse.paho.android.service.MqttAndroidClient.connect(MqttAndroidClient.java:428)
        at org.eclipse.paho.android.service.MqttAndroidClient.connect(MqttAndroidClient.java:334)
        at com.example.im_tierd_of_this_shit.MainActivity.getMqttClient(MainActivity.java:34)
        at com.example.im_tierd_of_this_shit.MainActivity.onCreate(MainActivity.java:29)
        at android.app.Activity.performCreate(Activity.java:8198)
        at android.app.Activity.performCreate(Activity.java:8182)
        at android.app.Instrumentation.callActivityOnCreate(Instrumentation.java:1309)
        at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:3765)
        at android.app.ActivityThread.handleLaunchActivity(ActivityThread.java:3968)
        at android.app.servertransaction.LaunchActivityItem.execute(LaunchActivityItem.java:85)
        at android.app.servertransaction.TransactionExecutor.executeCallbacks(TransactionExecutor.java:135)
        at android.app.servertransaction.TransactionExecutor.execute(TransactionExecutor.java:95)
        at android.app.ActivityThread$H.handleMessage(ActivityThread.java:2307)
        at android.os.Handler.dispatchMessage(Handler.java:106)
        at android.os.Looper.loop(Looper.java:246)
        at android.app.ActivityThread.main(ActivityThread.java:8512)
        at java.lang.reflect.Method.invoke(Native Method)
        at com.android.internal.os.RuntimeInit$MethodAndArgsCaller.run(RuntimeInit.java:602)
        at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:1130)
     Caused by: java.lang.ClassNotFoundException: Didn't find class "android.support.v4.content.LocalBroadcastManager" on path: DexPathList[[dex file "/data/data/com.example.im_tierd_of_this_shit/code_cache/.overlay/base.apk/classes3.dex", zip file "/data/app/~~W6OhEC-2fwAmOWAaC45Xyw==/com.example.im_tierd_of_this_shit-ghc3dmh_JMIqEeq5cr5lWg==/base.apk"],nativeLibraryDirectories=[/data/app/~~W6OhEC-2fwAmOWAaC45Xyw==/com.example.im_tierd_of_this_shit-ghc3dmh_JMIqEeq5cr5lWg==/lib/arm64, /system/lib64, /system/system_ext/lib64]]
        at dalvik.system.BaseDexClassLoader.findClass(BaseDexClassLoader.java:207)
        at java.lang.ClassLoader.loadClass(ClassLoader.java:379)
        at java.lang.ClassLoader.loadClass(ClassLoader.java:312)
        at org.eclipse.paho.android.service.MqttAndroidClient.registerReceiver(MqttAndroidClient.java:450) 
        at org.eclipse.paho.android.service.MqttAndroidClient.connect(MqttAndroidClient.java:428) 
        at org.eclipse.paho.android.service.MqttAndroidClient.connect(MqttAndroidClient.java:334) 
        at com.example.im_tierd_of_this_shit.MainActivity.getMqttClient(MainActivity.java:34) 
        at com.example.im_tierd_of_this_shit.MainActivity.onCreate(MainActivity.java:29) 
        at android.app.Activity.performCreate(Activity.java:8198) 
        at android.app.Activity.performCreate(Activity.java:8182) 
        at android.app.Instrumentation.callActivityOnCreate(Instrumentation.java:1309) 
        at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:3765) 
        at android.app.ActivityThread.handleLaunchActivity(ActivityThread.java:3968) 
        at android.app.servertransaction.LaunchActivityItem.execute(LaunchActivityItem.java:85) 
        at android.app.servertransaction.TransactionExecutor.executeCallbacks(TransactionExecutor.java:135) 
        at android.app.servertransaction.TransactionExecutor.execute(TransactionExecutor.java:95) 
        at android.app.ActivityThread$H.handleMessage(ActivityThread.java:2307) 
        at android.os.Handler.dispatchMessage(Handler.java:106) 
        at android.os.Looper.loop(Looper.java:246) 
        at android.app.ActivityThread.main(ActivityThread.java:8512) 
        at java.lang.reflect.Method.invoke(Native Method) 
        at com.android.internal.os.RuntimeInit$MethodAndArgsCaller.run(RuntimeInit.java:602) 
        at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:1130) 
W/System: A resource failed to call close. 
    A resource failed to call close. 

标签： javaandroideclipseandroid-studiomqtt