将Java bean用作Grails域类 [英] Using Java beans as Grails domain classes

问题描述

有很多类似的问题，但我无法在grails应用程序中找到如何使用POJO模型。考虑下面的Java Bean：

There are many similar questions, but I couldn't find exactly how to use a POJO model in a grails application. Consider the following Java Bean:

package com.example.java;

public class UserBean {

    String name;
    String surname;
    Integer age;

    //--- assume setters and getters here
}

和一个grails域的类：

and a grails domain class:

package com.example.grails

class User extends com.example.java.UserBean {

    static constraints = {
        name(blank:false)
        surname()
        age()
    }
}

和scaffold = true的伴随控制器。我不确定这是否应该起作用，但我没有看到任何其他建议。这编译和运行良好，直到我尝试从生成的视图添加一个新用户。然后我得到

and a companion controller with scaffold=true. I am not sure whether this supposed to work but I didn't see anything suggesting otherwise. This compiles and runs fine, until I try to add a new user from the generated view. Then I get

org.hibernate.MappingException: Unknown entity: com.example.grails.User

有什么想法？

Any ideas?

推荐答案

我在这个问题上找到了答案： this spring.io博客文章

I found the answer to this problem on: this spring.io blog post

如果您的Java域类是hibernate映射的，那么您不要在grails中扩展它们。您只需要在名为UserBeanConstraints.groovy的单独文件中定义约束：

If your Java domain classes are hibernate mapped, you don't extend them in grails. All you have to do is to define the constraints in a separate file named UserBeanConstraints.groovy:

constraints = {
    name(blank:false)
    surname()
    age()
}

这篇关于将Java bean用作Grails域类的文章就介绍到这了，希望我们推荐的答案对大家有所帮助，也希望大家多多支持IT屋！