如何在使用新生成的实体标识符时深度复制Hibernate实体 [英] How to deep copy a Hibernate entity while using a newly generated entity identifier

问题描述

我正在使用一个关系数据库，该数据库使用具有一些嵌套表的单列pk。

I'm using a relational DB using a single column pk with a few nested tables.

我需要向我的项目添加一个简单的归档。归档仅在应用程序达到特定状态时发生，因此我希望做的就是将现有的休眠对象复制到新实例中，在使用新ID保存新实例的同时，保持原有对象不变。

I need to add a simple archiving to my project. The archiving only happens when the application reaches a particular state, so what I was hoping to do was copy my existing hibernate object into a new instance where the new instance would be saved with a new ID while leaving the existing object intact.

我似乎无法找出如何将现有对象复制到新实例中，而无需手动设置每个新实例字段。

I can't seem to figure out how to copy the existing object into a new instance without manually having to set every single new instance field.

有人吗？知道执行此操作的简单方法吗？

Does anybody know of a simple way of doing this?

推荐答案

我也在使用Hibernate，并且得到了与您相同的要求。我所遵循的是实现 Cloneable 。下面是一个代码示例。

I am also working with Hibernate and I got the same requirement you got. What I followed was to implement Cloneable. Below is a code example of how to do it.

class Person implements Cloneable {

        private String firstName;
        private String lastName;

        public Object clone() {

            Person obj = new Person();
            obj.setFirstName(this.firstName);
            obj.setLastName(this.lastName);

            return obj;
        }

        public String getFirstName() {
            return firstName;
        }

        public void setFirstName(String firstName) {
            this.firstName = firstName;
        }

        public String getLastName() {
            return lastName;
        }

        public void setLastName(String lastName) {
            this.lastName = lastName;
        }
    }

或者您可以使用基于反射的解决方案，但我不会推荐的。请访问网站以获取更多详细信息。

Or you could go to a reflection based solution but I won't recommend that. Check this website for more details.

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