import javafx.beans.property.ObjectProperty; import javafx.beans.property.SimpleObjectProperty; public class ControllerInExpressionWrapper { private ObjectProperty controller = new SimpleObjectProperty<>(this, "controller"); public ObjectProperty controllerProperty() { return controller; } public ControllerInExpression getController() { return controller.get(); } public void setController(ControllerInExpression controller) { this.controller.set(controller); } }