안드로이드 현재시간 TextView 출력

public class MainActivity extends Activity {
 
    private TextView timeTv;
 
    private Timer mTimer;
 
 
    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_main);
 
        timeTv = (TextView) findViewById(R.id.timeTv);
 
        MainTimerTask timerTask = new MainTimerTask();
        mTimer = new Timer();
        mTimer.schedule(timerTask, 500, 1000);
 
 
    }
 
    private Handler mHandler = new Handler();
 
    private Runnable mUpdateTimeTask = new Runnable() {
        public void run() {
 
            Date rightNow = new Date();
            SimpleDateFormat formatter = new SimpleDateFormat(
                    "yyyy.MM.dd hh:mm:ss ");
            String dateString = formatter.format(rightNow);
            timeTv.setText(dateString);
 
        }
    };
 
    class MainTimerTask extends TimerTask {
        public void run() {
            mHandler.post(mUpdateTimeTask);
        }
    }
    @Override
    protected void onDestroy() {
        mTimer.cancel();
        super.onDestroy();
    }
 
    @Override
    protected void onPause() {
        mTimer.cancel();
        super.onPause();
    }
 
    @Override
    protected void onResume() {
        MainTimerTask timerTask = new MainTimerTask();
        mTimer.schedule(timerTask, 500, 3000);
        super.onResume();
    }
}