public static float getBorderLineWidth( JComponent c ) {
		FlatBorder border = getOutsideFlatBorder( c );
		return (border != null)
			? UIScale.scale( (float) border.getLineWidth( c ) )
			: 0;
	}
Returns the scaled line thickness used to compute the border insets.

@since 2
flatlaf-core/src/main/java/com/formdev/flatlaf/ui/FlatUIUtils.java