Swing获取字符串的宽度和高度

import java.awt.Color;
import java.awt.Font;
import java.awt.font.FontRenderContext;
import java.awt.geom.AffineTransform;

public class SwingUtil {
    private static AffineTransform atf = new AffineTransform();

    private static FontRenderContext frc = new FontRenderContext(atf, true,
            true);

    public static int getStringHeight(String str, Font font) {
        if (str == null || str.isEmpty() || font == null) {
            return ;
        }
        return (int) font.getStringBounds(str, frc).getWidth();

    }

    public static int getStringWidth(String str, Font font) {
        if (str == null || str.isEmpty() || font == null) {
            return ;
        }
        return (int) font.getStringBounds(str, frc).getWidth();
    }

    /**
     * 将形如“#FFFFFF”的颜色转换成Color
     *
     * @param hex
     * @return
     */
    public static Color getColorFromHex(String hex) {
        if (hex == null || hex.length() != ) {
            try {
                throw new Exception("不能转换这种类型的颜色");
            } catch (Exception e) {
                e.printStackTrace();
                return null;
            }
        }
        int r = Integer.valueOf(hex.substring(, ), );
        int g = Integer.valueOf(hex.substring(, ), );
        int b = Integer.valueOf(hex.substring(), );
        return new Color(r, g, b);
    }

}