code: private void defineSeparators(UIDefaults d) {
          String c = PAINTER_PREFIX + "SeparatorPainter";
          d.put("Separator.contentMargins", new InsetsUIResource(0, 0, 0, 0));
          d.put("Separator[Enabled].backgroundPainter", new LazyPainter(c, SeparatorPainter.Which.BACKGROUND_ENABLED));
      }
docs: Initialize the separator settings.
  
  @param d the UI defaults map.