onbackpressed android

1	@Override
2    public void onBackPressed() {
3        super.onBackPressed();
4    }

1@Override
2public void onBackPressed() {
3    new AlertDialog.Builder(this)
4        .setTitle("Really Exit?")
5        .setMessage("Are you sure you want to exit?")
6        .setNegativeButton(android.R.string.no, null)
7        .setPositiveButton(android.R.string.yes, new OnClickListener() {
8
9            public void onClick(DialogInterface arg0, int arg1) {
10                WelcomeActivity.super.onBackPressed();
11            }
12        }).create().show();
13}