问题描述

各位大神，小弟关于hibernate有一些疑问

我是实体类继承建立数据库表的问题
我先建立了一个
@MappedSuperclass
public abstract class AbEntity {
@Id
@GeneratedValue
private Integer id;
}
然后建立了User类 继承它
@Entity
@Table(name="user")
@Inheritance(strategy=InheritanceType.JOINED)
public class User extends AbstractEntity {
private String password;
private String name;
}
又建立了一个类 user2 继承User类
@Entity
@Table(name="user2")
public class Coach extends User {
private String age；
}
向数据库插入数据以后爆出了这样的错误
org.apache.catalina.core.StandardWrapperValve invoke
SEVERE: Servlet.service() for servlet [dispatcher] in context with path [] threw exception [Request processing failed; nested exception is org.hibernate.AssertionFailure: null id in com.icode.core.model.coach.Coach entry (don't flush the Session after an exception occurs)] with root cause
org.hibernate.AssertionFailure: null id in com.icode.core.model.coach.Coach entry (don't flush the Session after an exception occurs)

哪位大神帮助一下，谢谢了！

解决方案

跪求哪位大神来解答一下啊！