I am trying to import my existing Intel XDK Project in Android Studio.
Basically what I have is a html5 design with inappbrowser and some other plugins.
I wanted post data to external server using my app like logging in the user.
For that purpose I used HttpUrlConnection in Java Class.
I have working Java I want my Intel XDK Project to embed that class send user inputs to the class and retrieve the result in it.
Sounds like what you really need to do is build a custom plugin to wrap your Java code. Such development is outside the scope of the XDK. Please see the Cordova CLI plugin development docs and search the Internet for tutorials on how to build a Cordova plugin for additional help. Once you have a proper Cordova plugin you'll be able to add it to your Cordova app.