记一次安卓Handler.removeMessages引发的问题

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public class MainActivity extends AppCompatActivity {
    private static final String TAG = "MainActivity";
    private static final int MESSAGE_WHAT_SAY_HI = 0;
    private static final int MESSAGE_WHAT_SAY_HELLO = 1;
    private static class MyHandler extends Handler{
        @Override
        public void handleMessage(Message msg) {
            switch (msg.what){
                case MESSAGE_WHAT_SAY_HI:
                    Log.i(TAG, "hi");
                    break;
                case MESSAGE_WHAT_SAY_HELLO:
                    Log.i(TAG, "hello");
                    break;
            }
        }
    }
    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_main);
        Handler handler = new MyHandler();
        long delayTime = 5000;
        handler.postDelayed(new Runnable() {
            @Override
            public void run() {
                Log.i(TAG, "en....");
            }
        }, delayTime);
        handler.sendEmptyMessageDelayed(MESSAGE_WHAT_SAY_HI, delayTime);
        handler.sendEmptyMessageDelayed(MESSAGE_WHAT_SAY_HELLO, delayTime);
        handler.removeMessages(MESSAGE_WHAT_SAY_HI);
    }
}

以上代码输入为：

1
hello

而不是：

1
2
en....
hello