public void onFailure (Throwable cause)
    {
        _panel.clear();
        _panel.add(Widgets.newLabel(formatError(cause), "errorLabel"));
        Console.log("Service request failed", cause);
    }
public void onFailure ( Throwable cause ) { _panel . clear ( ) ; _panel . add ( Widgets . newLabel ( formatError ( cause ) , "errorLabel" ) ) ; Console . log ( "Service request failed" , cause ) ; }
from AsyncCallback<T>