private void removeInterest(SelectableChannel channel,int operation){
  SelectionKey key=channel.keyFor(selector);
  key.interestOps(key.interestOps() & (~operation));
}

private void removeInterest ( SelectableChannel channel , int operation ) { SelectionKey key = channel . keyFor ( selector ) ; key . interestOps ( key . interestOps ( ) & ( ~ operation ) ) ; }
remove one operation interest on a selectablechannel . the selectablechannel has to be registered with selector ahead . otherwise , nullpointerexceptions would throw the key for selectablechannel has to be valid . otherwise , invalidvalid exception would throw .
