Android java: Releasing resource Activity/Fragment <-> AndroidViewModel <-> MyController

Activity/Fragment <-> AndroidViewModel <-> MyController

MyController will hold

1. Executor
2. MediaController 
3. Network access
4. Database access
5. Application context for above operation  

Proper way to clear the resource

1. Executor
           // MyAndroidViewModel onClear() has been reached
        if (myExecutor!=null) {
            myExecutor.shutdown();
            myExecutor = null;
        }
2. Media Controller
           if (myMediaController!=null) {
            myMediaController.releaseMediaSession(); // MUST BE CLEAR
            myMediaController = null;
        }
3. Network access
           myGetRadioLogo=null;
4. Database access  
           myDBAccess=null;
5. Application context
           appContext=null; // MUST SET NULL AT ONCLEAR

Fail to release these resources may lead to memory leak

Fail to release resource with not properly sequence may lead application crashed, this crash can be found on logcat.