Resets this watch key.

If this watch key has been cancelled or this watch key is already in the ready state then invoking this method has no effect. Otherwise if there are pending events for the object then this watch key is immediately re-queued to the watch service. If there are no pending events then the watch key is put into the ready state and will remain in that state until an event is detected or the watch key is cancelled.

Returns:  true if the watch key is valid and has been reset, and false if the watch key could not be reset because it is no longer valid