// layouter: voidfunc(Container)
// or func(Container) -> Dimension [preferred size]
// or func(Container) -> Pair(Dimension, Dimension) [preferred, minimum]
static JPanel customLayoutPanel(fO layouter) {
  ret jpanel(layoutManagerFromFunction(layouter));
}

static JPanel customLayoutPanel(fO layouter, fL<? extends Component> components) {
  ret addAllComponents(customLayoutPanel(layouter), components);
}

static JPanel customLayoutPanel(LayoutManager layouter, Component... components) {
  ret addAllComponents(customLayoutPanel(layouter), components);
}