private Icon getHelpIcon(JTable table, int currentColumnIndex) {

		JTableHeader tableHeader = table.getTableHeader();
		if (!(tableHeader instanceof GTableHeader)) {
			return EMPTY_ICON;
		}

		GTableHeader tooltipTableHeader = (GTableHeader) tableHeader;
		int hoveredColumnIndex = tooltipTableHeader.getHoveredHeaderColumnIndex();
		if (hoveredColumnIndex != currentColumnIndex) {
			return EMPTY_ICON;
		}

		Icon icon = tooltipTableHeader.getHelpIcon();
		if (icon != null) {
			return icon;
		}
		return EMPTY_ICON;
	}
Paints a background highlight under the icon that will get painted.
@param g2d the graphics
@param scale the current scale, up to max 
@param max the max emphasis size
@param ix the icon x
@param iy the icon y
@param iw the icon width
@param ih the icon height
Ghidra/Framework/Docking/src/main/java/docking/widgets/table/GTableHeaderRenderer.java