FirstActivity继承了BaseActivity，重写了onCreate，为什么还会执行父类

BaseActivity是这样的，有个Log打印的代码

public class BaseAcitivity extends Activity {
 @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        Log.d("BaseActivity", getClass().getSimpleName());
    }
}

FirstActivity、SecondActivity、ThirdActivity继承了BaseActivity，有自己的onCreate为什么还会执行父类的Log的打印，不是会覆盖吗？

 public class FirstActivity extends BaseAcitivity {

    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_first);
    }

    public void start_second(View view){
        Intent intent = new Intent(this, SecondActivity.class);
        startActivity(intent);
    }
}

SecondActivity、ThirdActivity跟FirstActivity一样，就不贴了，求大神指点啊

01-18 02:32:36.040: D/BaseActivity(1223): FirstActivity
01-18 02:32:39.576: D/BaseActivity(1223): SecondActivity
01-18 02:32:44.188: D/BaseActivity(1223): ThirdActivity

super.onCreate(savedInstanceState);
这就调用了父类的onCreate