问题描述
主题说明了一切......到目前为止,我认为人们在 getter 和/或 setter 上声明注释没有任何优势.对我来说,这只是将注释分散到类中的缺点,这会使类更不可读.
Subject says it all... I see no advantage of people declaring annotations on the getters and/or setters so far. For me this only has the disadvantage of spreading the annotations over the class, which can make the class more unreadable.
在字段上添加注释明显减少了需要帮助时发布的代码量.不过,这只是一个很小的优势.但是在方法上添加注释对我来说毫无用处.
Putting the annotations on the fields clearly reduces the amount of code to post when needing help. This is just a tiny advantage though. But putting annotations on methods would serve no purpose to me.
推荐答案
在方法上添加注释会强制 JPA 通过方法访问属性.当对象的内部状态与数据库模式不同时,这是有意义的:
Putting annotations on methods forces JPA to access properties via methods. It makes sense when internal state of your object differs from the database schema:
@Entity public class Employee { private String firstName; private String lastName; @Column(name = "EMP_NAME") // Due to legacy database schema public String getName() { return fisrtName + " " + lastName; } public void setName(String name) { ... } ... Getters and setters for firstName and lastName with @Transient ... }
在 JPA 2.0 中,您可以使用 @Access 在细粒度级别指定访问类型:
In JPA 2.0 you can specify access type at fine-grained level with @Access:
@Entity @Access(AccessType.FIELD) public class Employee { @Access(AccessType.PROPERTY) @Column(name = "EMP_NAME") public String getName() { ... } ... other properties have field access ... }