# File lib/methods.rb, line 837
def validate_eui(eui)
    if (eui.kind_of?(String))
        # check for invalid characters
        if (eui =~ /[^0-9a-fA-F\.\-\:]/)
            raise ValidationError, "#{eui} is invalid (contains invalid characters)."
        end

        # split on formatting characters & check lengths
        if (eui =~ /\-/)
            fields = eui.split('-')
            if (fields.length != 6 && fields.length != 8)
                raise ValidationError, "#{eui} is invalid (unrecognized formatting)."
            end
            fields.each {|x| raise ValidationError, "#{eui} is invalid (missing characters)." if (x.length != 2)} 
        elsif (eui =~ /\:/)
            fields = eui.split(':')
            if (fields.length != 6 && fields.length != 8)
                raise ValidationError, "#{eui} is invalid (unrecognized formatting)."
            end
            fields.each {|x| raise ValidationError, "#{eui} is invalid (missing characters)." if (x.length != 2)}
        elsif (eui =~ /\./)
            fields = eui.split('.')
            if (fields.length != 3 && fields.length != 4)
                raise ValidationError, "#{eui} is invalid (unrecognized formatting)."
            end
            fields.each {|x| raise ValidationError, "#{eui} is invalid (missing characters)." if (x.length != 4)}
        else
            raise ValidationError, "#{eui} is invalid (unrecognized formatting)."
        end

    else
        raise ArgumentError, "EUI address should be a String, but was a#{eui.class}."
    end
    return(true)
end