public void getResult (ResultListener<T> rl)
    {
        if (_error != null) {
            rl.requestFailed(_error);
        } else if (_list == null) { // _list == null when we have a result
            rl.requestCompleted(_result);
        } else {
            _list.add(rl);
        }
    }
public void getResult ( ResultListener < T > rl ) { if ( _error != null ) { rl . requestFailed ( _error ) ; } else if ( _list == null ) { rl . requestCompleted ( _result ) ; } else { _list . add ( rl ) ; } }
Retrieves the result for the specified listener.  If the result is already available (or the
request failed), the listener will receive an immediate response.  Otherwise, the listener
will be added to the list and notified when the result is available.