if (getChannel().isOpen() && _key.isValid())
if (isOpen())
        public void blockReadable(long timeoutMs)        {            synchronized (this)            {                if (getChannel().isOpen() && _key.isValid())                {                    try                    {                        _readBlocked++;                        updateKey();                        this.wait(timeoutMs);                    }                    catch (InterruptedException e)                    {                        e.printStackTrace();                    }                    finally                    {                        _readBlocked--;                    }                }            }        }