@Override
	public void paintBorder( Component c, Graphics g, int x, int y, int width, int height ) {
		// paint grip
		if( c instanceof JToolBar && ((JToolBar)c).isFloatable() ) {
			Graphics2D g2 = (Graphics2D) g.create();
			try {
				FlatUIUtils.setRenderingHints( g2 );

				Color color = getStyleFromToolBarUI( c, ui -> ui.gripColor );
				g2.setColor( (color != null) ? color : gripColor );
				paintGrip( c, g2, x, y, width, height );
			} finally {
				g2.dispose();
			}
		}
	}
Border for {@link javax.swing.JToolBar}.

@uiDefault ToolBar.borderMargins				Insets
@uiDefault ToolBar.gripColor					Color

@author Karl Tauber
flatlaf-core/src/main/java/com/formdev/flatlaf/ui/FlatToolBarBorder.java