这个库可以为多个服务器提供连接机会吗？ https://github.com/eclipse/paho.mqtt.android
我无法在源代码中找出这种情况
例如：
mqttAndroidClient1 = new MqttAndroidClient(getApplicationContext(), "tcp://iot.eclipse.org:1883", clientId);
mqttAndroidClient2 = new MqttAndroidClient(getApplicationContext(), "tcp://iot.blablabla.org:1883", clientId);
....
mqttAndroidClient1.connect(...)
mqttAndroidClient2.connect(...)
答案 0 :(得分：0)
确定。这是工作。我通过我的语言环境设备和此服务https://iot.eclipse.org/getting-started#sandboxes进行了测试。
public class MainActivity extends AppCompatActivity {
private final String TAG = this.getClass().getSimpleName();
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
}
Handler mHandler = new Handler();
MqttAndroidClient mqttAndroidClient1;
MqttAndroidClient mqttAndroidClient2;
String clientId = "ExampleAndroidClient";
final String serverUri = "tcp://iot.eclipse.org:1883";
final String serverUri2 = "tcp://192.168.10.11:1883" ;
@Override
protected void onStart() {
super.onStart();
clientId = clientId + System.currentTimeMillis();
mqttAndroidClient2 = new MqttAndroidClient(getApplicationContext(), serverUri2, clientId+"2");
mqttAndroidClient2.setCallback(new MqttCallbackExtended() {
@Override
public void connectComplete(boolean reconnect, String serverURI) {
if (reconnect) {
Log.i(TAG,"Reconnected to : " + serverURI);
// Because Clean Session is true, we need to re-subscribe
subscribeToTopic2();
} else {
Log.i(TAG,"Connected to: " + serverURI);
}
}
@Override
public void connectionLost(Throwable cause) {
Log.w(TAG,"The Connection was lost.");
}
@Override
public void messageArrived(String topic, MqttMessage message) throws Exception {
Log.i(TAG,"Incoming message: " + new String(message.getPayload()));
}
@Override
public void deliveryComplete(IMqttDeliveryToken token) {
}
});
mqttAndroidClient1 = new MqttAndroidClient(getApplicationContext(), serverUri, clientId);
mqttAndroidClient1.setCallback(new MqttCallbackExtended() {
@Override
public void connectComplete(boolean reconnect, String serverURI) {
if (reconnect) {
Log.i(TAG,"Reconnected to : " + serverURI);
// Because Clean Session is true, we need to re-subscribe
subscribeToTopic1();
} else {
Log.i(TAG,"Connected to: " + serverURI);
}
}
@Override
public void connectionLost(Throwable cause) {
Log.w(TAG,"The Connection was lost.");
}
@Override
public void messageArrived(String topic, MqttMessage message) throws Exception {
Log.i(TAG,"Incoming message: " + new String(message.getPayload()));
}
@Override
public void deliveryComplete(IMqttDeliveryToken token) {
}
});
MqttConnectOptions mqttConnectOptions = new MqttConnectOptions();
mqttConnectOptions.setAutomaticReconnect(true);
mqttConnectOptions.setCleanSession(false);
try {
//addToHistory("Connecting to " + serverUri);
mqttAndroidClient1.connect(mqttConnectOptions, null, new IMqttActionListener() {
@Override
public void onSuccess(IMqttToken asyncActionToken) {
DisconnectedBufferOptions disconnectedBufferOptions = new DisconnectedBufferOptions();
disconnectedBufferOptions.setBufferEnabled(true);
disconnectedBufferOptions.setBufferSize(100);
disconnectedBufferOptions.setPersistBuffer(false);
disconnectedBufferOptions.setDeleteOldestMessages(false);
mqttAndroidClient1.setBufferOpts(disconnectedBufferOptions);
subscribeToTopic1();
}
@Override
public void onFailure(IMqttToken asyncActionToken, Throwable exception) {
Log.e(TAG,"Failed to connect to: " + mqttAndroidClient1.getServerURI());
}
});
} catch (MqttException ex){
ex.printStackTrace();
}
try {
//addToHistory("Connecting to " + serverUri);
mqttAndroidClient2.connect(mqttConnectOptions, null, new IMqttActionListener() {
@Override
public void onSuccess(IMqttToken asyncActionToken) {
DisconnectedBufferOptions disconnectedBufferOptions = new DisconnectedBufferOptions();
disconnectedBufferOptions.setBufferEnabled(true);
disconnectedBufferOptions.setBufferSize(100);
disconnectedBufferOptions.setPersistBuffer(false);
disconnectedBufferOptions.setDeleteOldestMessages(false);
mqttAndroidClient2.setBufferOpts(disconnectedBufferOptions);
subscribeToTopic2();
}
@Override
public void onFailure(IMqttToken asyncActionToken, Throwable exception) {
Log.e(TAG,"Failed to connect to: " + mqttAndroidClient2.getServerURI());
}
});
} catch (MqttException ex){
ex.printStackTrace();
}
}
@Override
protected void onStop() {
super.onStop();
}
public void subscribeToTopic1(){
String subscriptionTopic = "/uwblogs";
try {
mqttAndroidClient1.subscribe(subscriptionTopic, 0, null, new IMqttActionListener() {
@Override
public void onSuccess(IMqttToken asyncActionToken) {
Log.i(TAG,"Subscribed!");
}
@Override
public void onFailure(IMqttToken asyncActionToken, Throwable exception) {
Log.i(TAG,"Failed to subscribe");
}
});
mqttAndroidClient1.subscribe(subscriptionTopic, 0, new IMqttMessageListener() {
@Override
public void messageArrived(String topic, MqttMessage message) throws Exception {
// message Arrived!
final String str = new String(message.getPayload());
mHandler.post(new Runnable() {
@Override
public void run() {
((TextView)findViewById(R.id.textView_server1)).setText(str);
}
});
Log.i(TAG,"Message: " + topic + " : " + new String(message.getPayload()));
}
});
} catch (MqttException ex){
System.err.println("Exception whilst subscribing");
ex.printStackTrace();
}
}
public void subscribeToTopic2(){
String subscriptionTopic = "/devices/wb-adc/controls/Vin";
try {
mqttAndroidClient2.subscribe(subscriptionTopic, 0, null, new IMqttActionListener() {
@Override
public void onSuccess(IMqttToken asyncActionToken) {
Log.i(TAG,"Subscribed!");
}
@Override
public void onFailure(IMqttToken asyncActionToken, Throwable exception) {
Log.i(TAG,"Failed to subscribe");
}
});
mqttAndroidClient2.subscribe(subscriptionTopic, 0, new IMqttMessageListener() {
@Override
public void messageArrived(String topic, MqttMessage message) throws Exception {
// message Arrived!
final String str = new String(message.getPayload());
mHandler.postAtFrontOfQueue(new Runnable() {
@Override
public void run() {
((TextView)findViewById(R.id.textView_server2)).setText(str);
}
});
Log.i(TAG,"Message server2: " + topic + " : " + new String(message.getPayload()));
}
});
} catch (MqttException ex){
System.err.println("Exception whilst subscribing");
ex.printStackTrace();
}
}
}