我必须重写复合id（xml）到JPA

Question

这是我的xml映射。我需要JPA映射

<composite-id> 
     <key-property name="systemId" type="integer" column="SYSTEM_ID"/> 
     <key-property name="rollingRackId" type="integer" column="ROLLING_RACK_ID"/> 
    </composite-id> 

    <property name="status" type="integer" column="ROLLING_RACK_STATUS"/> 
    <property name="changeTime" type="timestamp" column="CHANGE_TIME" /> 

</class> 

Answer 1

你必须引入一个ID类

@Entity @IdClass(KeyClass.class) 
public class Entity{ 
    @Id int systemId; 
    @Id int rollingRackId; 

} 


class KeyClass{ 
    int systemId; 
    int rollingRackId; 
} 

见the example