如何在Hibernate中映射一组枚举类型？ [英] How to map a set of enum type in Hibernate?

问题描述

在hibernate中，是否可以为一个类定义映射到一组枚举？

我已经能够找到如何定义集合映射的示例，并且我已经能够找到单独的示例来说明如何映射枚举，但是我无法确定了解如何定义一个类的枚举。

任何人都可以给我一个例子吗？

这是建立在现有应用程序之上的，因此我无法更改数据库模式。

这是我希望建模的关系。 Wicket是一个普通的类，WicketType是一个Java Enum。

  + ------------- --- + + ------------ + + ------------ + 
 | Wicket | |参考表| | WicketType | 
 + ---------------- + + ------------ + + ------------ + 
 | INT | W_ID | | | | W_TypeId | 
 | .... | | FK | W_ID | FK | WicketType | 
 | INT | TYPE | ---- | W_TypeId | ---- | | 
 + ---------------- + + ------------ + + ------------ + 
  

再次感谢

解决方案

这个

a>没有做你需要的东西？

为了详细说明翻转初始响应，引用提供了使用枚举的序数来枚举枚举的方法。

在这种情况下，它实际上比它看起来更简单，因为您将枚举托管在一个集合中，您需要为WicketType的子类型IntEnumUserType提供一个访问器，超类型将负责将序号映射到实例。

  package test; 
 
 public class WicketTypeState extends IntEnumUserType< WicketType> {
私人WicketType wicketType; 
 
 public WicketTypeState（）{
 //我们必须将枚举值赋给父类。 
 super（WicketType.class，WicketType.values（））; 
} 
 
 public WicketType getWicketType（）{
 return wicketType; 
} 
 
 public void setWicketType（final WicketType wicketType）{
 this.wicketType = wicketType; 
 
 
 
 
 
 
 
定义枚举表的映射：
 < hibernate-mapping package =test> 
< class name =Wickettable =Wicket> 
< id name =idcolumn =ID/> 
< set name =wicketTypestable =WicketTypeinverse =true> 
< key column =ID/> 
 < / set> 
< / class> 
< / hibernate-mapping> 
  
然后，对于具有一组枚举的类型，定义该属性的集合映射：
 < hibernate-mapping package =test> 
< class name =WicketTypeStatelazy =truetable =WicketType> 
< id name =WicketType
 type =test.WicketTypeState/> 
< / class> 
< / hibernate-mapping> 
  
这个工作在我的盒子（tm）上，让我知道你是否需要更多的信息。
 
In hibernate, is it possible to define a mapping for a class to a set of enums?  

I've been able to find examples of how to define mappings of Sets and I've been able to find separate examples for how to map Enums, but I cannot figure out how to define a  of Enums for a class.

Could anyone please provide me with an example?  

This is being built on top of an existing application, so I cannot alter the database schema. 

This is the relation I wish to model.  Wicket is a normal class and WicketType is a Java Enum.
+----------------+    +------------+    +------------+
| Wicket         |    | Ref Table  |    | WicketType |
+----------------+    +------------+    +------------+
| INT     | W_ID |    |            |    | W_TypeId   |
| ....    |      | FK | W_ID       | FK | WicketType |
| INT     | TYPE |----| W_TypeId   |----|            |
+----------------+    +------------+    +------------+
Thanks again
解决方案
Does this not do what you need?

To elaborate on the flippant initial response, the reference provides a means to use the ordinal of the enum to map enumerations.

In this case it's actually simpler than it looks, because you are hosting the enums in a set, you need to provide an accessor for the WicketType to the sub-type of IntEnumUserType, the super-type will take care of mapping the ordinal to the instance.
package test;

public class WicketTypeState extends IntEnumUserType<WicketType> {
    private WicketType wicketType;

public WicketTypeState() {
    // we must give the values of the enum to the parent.
    super(WicketType.class, WicketType.values());
}

    public WicketType getWicketType() {
        return wicketType;
    }

    public void setWicketType(final WicketType wicketType) {
        this.wicketType = wicketType;
    }
}
Define the mappings for the enum table:
<hibernate-mapping package="test">  
  <class name="Wicket" table="Wicket">
    <id name="id" column="ID"/>
    <set name="wicketTypes" table="WicketType" inverse="true">
      <key column="ID"/>
      <one-to-many class="test.WicketTypeState"/>
    </set>
  </class>
</hibernate-mapping>
Then for the type with the set of enums, define a set mapping for that property:
<hibernate-mapping package="test">
  <class name="WicketTypeState" lazy="true" table="WicketType">
    <id name="WicketType" 
      type="test.WicketTypeState"/>
  </class>
</hibernate-mapping>
This worked on my box(tm), let me know if you need any more info.

                        
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