The use of the method setControllerFactory in FXMLLoader hides occurrent Exceptions in the initialize() method in FXML Controllers.
In our case Guice is used to instantiate the controllers. If you set
int i = 1/0;
in initialize, an ArithmeticException should be thrown instead of a java.lang.reflect.InvocationTargetException.
It works normally without a custom ControllerFactory.