message
调用此方法生成错误对象,当无法克隆对象时将抛出该错误对象。
此方法默认为 Error 构造函数,并且可以在子类上覆盖。
Error
This method is called to generate error objects that will be thrown when an object can not be cloned.
This method defaults to the Error constructor and can be overridden on subclasses.