push notification - Unregister a device from GCM using registration Id in Android

Question

I have a list of GCM registered users and their corresponding registration Ids in a database table, and I actually want to unregister a user whenever he/she is deleted from the table. I found a lot of examples here in Stackoverflow, but most of them are based on the old GCMRegistrar API which is now deprecated. I'm using GoogleCloudMessaging API and registering a user by following method:

private void registerUser(){
        GoogleCloudMessaging gcm = GoogleCloudMessaging.getInstance(getBaseContext());
        String regId = "";
        try {
            regId = gcm.register(getString(R.string.project_number));
            Log.i("registrationId", regId);
        } 
        catch (IOException e) {
            Log.i("Registration Error", e.getMessage());
        }
}

I have an administrator app, which acts as a 3rd-party application server, since it pushes notifications to all users. I want to unregister a specific user from this administrator app with following method:

private void unRegister(String regId) {

        GoogleCloudMessaging gcm = GoogleCloudMessaging.getInstance(getBaseContext());
        try {
            gcm.unregister();
        } 
        catch (IOException e) {     
        System.out.println("Error Message: " + e.getMessage());
        }

   }

But it confuses me that unregister() method does not take registration Id as an argument, which makes it impossible to unregister a specific device. Is there any way to unregister a specific device from GCM by registration Id ?.

Answer 1

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