Class ColorHelper


  • public final class ColorHelper
    extends Object

    A helper class for dealing with colors.

    This class defines helper methods for converting color values specified in form builder Jelly scripts. In this model colors can be defined in the following different ways:

    • Using a symbolic name. For this purpose this class defines constants that roughly correspond to the colors defined by the java.awt.Color class.
    • As a hexadecimal numeric value. In this case the color definition must start with a "#" sign, e.g. #80FF80. This is analogous to color definitions in HTML.
    • As triple of decimal rgb values. Definitions of this type look like (r, g, b), with r, g, b in the range from 0 to 255.
    • Logic color definitions. These are arbitrary strings which are not further interpreted, e.g. style sheet names. To be recognized, such a string must start with a "~" character, e.g. ~MyStyle.

    Version:
    $Id: ColorHelper.java 205 2012-01-29 18:29:57Z oheger $
    Author:
    Oliver Heger
    • Method Detail

      • getPredefinedColor

        public static Color getPredefinedColor​(String name)
                                        throws FormBuilderException
        Returns the predefined color with the given name. The passed in name must be one of the names returned by the getPredefinedNames() method (case does not matter).
        Parameters:
        name - the name of the desired color
        Returns:
        the color
        Throws:
        FormBuilderException - if this color does not exist
      • getPredefinedNames

        public static Iterator<String> getPredefinedNames()
        Returns an iterator with the names (Strings) of all predefined colors. These names can be passed to the getPredefinedColor() method.
        Returns:
        the names of the predefined colors
      • resolveColor

        public static Color resolveColor​(String c)
                                  throws FormBuilderException
        The main method for resolving a color definition. This method can be given a color definition in one of the supported flavors. It will try to resolve this definition and return the corresponding Color object. If this fails, an exception will be thrown.
        Parameters:
        c - the color definition
        Returns:
        the corresponding color object or null if the passed in color definition was null
        Throws:
        FormBuilderException - if the color definition cannot be resolved