Try This..
int x = 0;
int y = 0;
public void shakeStage() {
Timeline timelineX = new Timeline(new KeyFrame(Duration.seconds(0.1), new EventHandler<ActionEvent>() {
@Override
public void handle(ActionEvent t) {
if (x == 0) {
primaryStage.setX(primaryStage.getX() + 10);
x = 1;
} else {
primaryStage.setX(primaryStage.getX() - 10);
x = 0;
}
}
}));
timelineX.setCycleCount(Timeline.INDEFINITE);
timelineX.setAutoReverse(false);
timelineX.play();
Timeline timelineY = new Timeline(new KeyFrame(Duration.seconds(0.1), new EventHandler<ActionEvent>() {
@Override
public void handle(ActionEvent t) {
if (y == 0) {
primaryStage.setY(primaryStage.getY() + 10);
y = 1;
} else {
primaryStage.setY(primaryStage.getY() - 10);
y = 0;
}
}
}));
timelineY.setCycleCount(Timeline.INDEFINITE);
timelineY.setAutoReverse(false);
timelineY.play();
}