def method=(method)
      validator = EnumAttributeValidator.new('String', ["ENUM", "FC"])
      unless validator.valid?(method)
        fail ArgumentError, "invalid value for 'method', must be one of #{validator.allowable_values}."
      end
      @method = method
    end
def method=(method)
      validator = EnumAttributeValidator.new('String', ["ENUM", "FC"])
      unless validator.valid?(method)
        fail ArgumentError, "invalid value for 'method', must be one of #{validator.allowable_values}."
      end
      @method = method
    end
Custom attribute writer method checking allowed values (enum).
 @param [Object] method Object to be assigned