SoundManager和monitorenter和monitorexit

Question

我尝试使用monitorenter和monitorexite控制声音这个代码我使用但是这对我来说不起作用这些erorrs显示：monitorenter无法解析为变量，monitorenter无法解析为变量，localObject无法解析为变量

 public static SoundManager getInstance()
 {
  monitorenter;
    try
    {
      if (_instance == null)
        _instance = new SoundManager();
      SoundManager localSoundManager = _instance;
      monitorexit;
      return localSoundManager;
    }
    finally
    {
      localObject = finally;
      monitorexit;
    }
    throw localObject;
}