In-depth understanding of the technical implementation of Play Services GCM in the Java class library (In-Depth UNDERSTANDINGINGINGINGINGINGINGINGINGINGINGAL Implementation of Play Services GCM in Java Class Libraares)
Knowing the technology implementation of Play Services GCM in the Java class library
Play Services GCM (Google Cloud Messaging) is a cloud message transmission service provided by Google, which enables developers to easily implement message push functions in mobile applications.In the Java class library, the technology implementation of Play Services GCM mainly involves the following aspects: registered devices, send messages, and processes received messages.
1. Equipment registration
Before using Play Services GCM, the application needs to register the device to the GCM server to obtain a unique registration ID.Registering ID is an important sign of communication between applications and devices.The following is an example of a Java code, which shows how to register the device through Play Services GCM:
public class GcmRegistrationService extends IntentService {
private static final String SENDER_ID = "your_sender_id";
public GcmRegistrationService() {
super("GcmRegistrationService");
}
@Override
protected void onHandleIntent(Intent intent) {
try {
GoogleCloudMessaging gcm = GoogleCloudMessaging.getInstance(this);
String registrationId = gcm.register(SENDER_ID);
// Send the registration ID to the application server for association processing
} catch (IOException e) {
// Treatment abnormal situation
}
}
}
2. Send message
Once the device is successfully registered to the GCM server, the application can use the registration ID to send the message to a specific device.The following Java code example shows how to use Play Services GCM to send messages:
public class GcmMessageSender {
private static final String API_KEY = "your_api_key";
public void sendMessage(String registrationId, String message) {
try {
Sender sender = new Sender(API_KEY);
Message gcmMessage = new Message.Builder()
.addData("message", message)
.build();
Result result = Sender.Send (GCMMESSAGE, Registryidid, 3); // Repeat 3 times
// Make corresponding treatment according to the results of the sending
} catch (IOException | InvalidRequestException | UnauthorizedException | ServerException | RetryAfterException e) {
// Treatment abnormal situation
}
}
}
3. process the receiving message
When the device receives a message sent through Play Services GCM, you need to realize a BroadcastReceiver in the application to process these messages.The following is an example of Java code, showing how to handle the received messages:
public class GcmBroadcastReceiver extends BroadcastReceiver {
@Override
public void onReceive(Context context, Intent intent) {
Bundle extras = intent.getExtras();
if (extras != null && !extras.isEmpty()) {
GoogleCloudMessaging gcm = GoogleCloudMessaging.getInstance(context);
String messageType = gcm.getMessageType(intent);
if (GoogleCloudMessaging.MESSAGE_TYPE_MESSAGE.equals(messageType)) {
String message = extras.getString("message");
// Process the receiving message
}
}
}
}
Through the above examples, we can see that the technology implementation of Play Services GCM involves the registration and reception of the device, and the relevant API provided by the Java library is implemented.This enables developers to easily and quickly implement the function of push messages in mobile applications.
