static JSplitPane jvsplit(Component north, Component south) {
  ret jvsplit(north, south, 0.5);
}

static JSplitPane jvsplit(Component north, Component south, double splitPoint) {
  ret setSplitPaneLater(
    swingNu(JSplitPane.class, JSplitPane.VERTICAL_SPLIT, wrap(north), wrap(south)),
    splitPoint);
}