@Override
  protected void installDefaults() {
    final int incGap = UIManager.getInt("ScrollBar.incrementButtonGap");
    final int decGap = UIManager.getInt("ScrollBar.decrementButtonGap");
    try {
      UIManager.put("ScrollBar.incrementButtonGap", 0);
      UIManager.put("ScrollBar.decrementButtonGap", 0);
      super.installDefaults();
    }
    finally {
      UIManager.put("ScrollBar.incrementButtonGap", incGap);
      UIManager.put("ScrollBar.decrementButtonGap", decGap);
    }

    myMacScrollerStyle = NSScrollerHelper.getScrollerStyle();
    scrollbar.setFocusable(false);
    updateStyleDefaults();
  }
@Override
  protected void installDefaults()