private static boolean isVerticalScrollBarNeeded(Component view, Point location, Dimension preferredSize, Dimension extentSize) {
      // don't bother Scrollable.getScrollableTracksViewportHeight if a vertical scroll bar is not needed
      return isScrollBarNeeded(location.y, preferredSize.height, extentSize.height) && !tracksViewportHeight(view);
    }
private static boolean isVerticalScrollBarNeeded(Component view, Point location, Dimension preferredSize, Dimension extentSize)