FillLayoutPane fillLayout = new FillLayoutPane();
fillLayout.setStyle("-fx-background-color: red");
fillLayout.setMarginHeight(5);
fillLayout.setMarginWidth(5);
SashLayoutPane sashLayout = new SashLayoutPane();
sashLayout.setStyle("-fx-background-color: blue");
sashLayout.getRoot().setHorizontal(true);
Label l = new Label();
l.setStyle("-fx-background-color: white");
SashLayoutPane.MUIControl data = new SashLayoutPane.MUIControl();
data.setWeight(49.81605562579014);
sashLayout.getRoot().add(data);
sashLayout.getChildren().add(l);
sashLayout.setConstraint(l, data);
l = new Label();
l.setStyle("-fx-background-color: white");
data = new SashLayoutPane.MUIControl();
data.setWeight(50.377192982456144);
sashLayout.getRoot().add(data);
sashLayout.getChildren().add(l);
sashLayout.setConstraint(l, data);
fillLayout.getChildren().add(sashLayout);
tab.setContent(fillLayout);