public void addLayoutComponent(String key, Component component) {
		if (key == JScrollPane.VIEWPORT)
			viewport = component;
		else if (key == JScrollPane.VERTICAL_SCROLLBAR)
			vsb = (JScrollBar) component;
		else if (key == JScrollPane.HORIZONTAL_SCROLLBAR)
			hsb = (JScrollBar) component;
		else if (key == JScrollPane.ROW_HEADER)
			rowHead = component;
		else if (key == JScrollPane.COLUMN_HEADER)
			colHead = component;
		else if (key == JScrollPane.LOWER_RIGHT_CORNER)
			lowerRight = component;
		else if (key == JScrollPane.UPPER_RIGHT_CORNER)
			upperRight = component;
		else if (key == JScrollPane.LOWER_LEFT_CORNER)
			lowerLeft = component;
		else if (key == JScrollPane.UPPER_LEFT_CORNER)
			upperLeft = component;
	}