Q:

In Google cloud messaging for android

In my android application, i need to do push notification so, i searched for that and i found Google Cloud Messaging at android guide, step by step procedure. 
In Writing the Android Application
Step 3: Write the my_app_package. GCMIntentService class 
i need to create GCMIntentService class extended from GCMBaseIntentService and i need to implement abstract methods(onRegistered,onUnregistered,etc) in GCMBaseIntentService and in onRegistered method i should send the regid to your server so it can use it to send messages to device. 
I got Cordova GCM Push Notifications Plugin for Android example from here 
1) there i saw they implemented GCMIntentService class (at src/com/cordova2/gcm), in that class, see onRegistered method, after getting json i don't know why they are calling GCMPlugin.sendJavascript( json ) in line 39?. 
2) how to develop client and server for push notification using Google cloud messaging 

A:

check following link for Android Push notification With server code=
    http://www.androidhive.info/2012/10/android-push-notifications-using-google-cloud-messaging-gcm-php-and-mysql/

