How to destroy an activity in other activity in Android?

Create a static Activity object which activity finish on other activity and assign activity in this i.e you can can add more activities

public class demoActivity extends AppCompatActivity {
    public static Activity self_intent;
    protected void onCreate(Bundle savedInstanceState) {
            super.onCreate(savedInstanceState);
            setContentView(R.layout.demo_activity);
            selfintent=this;
    } 

   //Other functions--------------
} 

do same for other activities on other

public class finishingActivity extends AppCompatActivity {
        public Button activityCloseBtn;
        protected void onCreate(Bundle savedInstanceState) {
            super.onCreate(savedInstanceState);
            setContentView(R.layout.finishing_activity);

            activityCloseBtn= (Button) view.findViewById(R.id.activity_close_btn);
            activityCloseBtn.setOnClickListener(new View.OnClickListener() {      
            @Override
            public void onClick(View v) {
               demoActivity.selfintent.finish(); //for finish demoActivityactivity

              //for other activities Activity.selfintent.finish();
               finish();  //for finish current activity
          }
    });