Java 具有抽象关系类的抽象类

为了便于实现，我想创建一个相关的抽象类结构

这是一个DB模型示例：

摘要A：

@MappedSuperclass
public abstract class AbstractClassA<T, R> {

   @Id
   Long id;

   @ManyToOne(fetch = FetchType.LAZY)
   @JoinColumn(name = "field", nullable = false)
   private ClassA<R> classA;

   @OneToMany(fetch = FetchType.EAGER, mappedBy = "concreteA")
   private Set<T> concreteB = new HashSet<T>(0);

}

可以创建这个类模式吗？如果是这样，我哪里做错了

---

谢谢

您是否检查了服务器给您的提示？你也可以看看这个例子

@MappedSuperclass
public abstract class AbstractClassB<T> {

   @EmbeddedId
   CompositeId id;

   @ManyToOne(fetch = FetchType.LAZY)
   @JoinColumn(name = "id")
   private T concreteA;

}

@Entity
@Table
public class ClassA<T> {

   @Id
   Long id;

   @OneToMany(fetch = FetchType.LAZY, mappedBy = "classA")
   private Set<T> concreteA = new HashSet<T>(0);

}

@Entity
@Table
public class ConcreteA extends AbstractA<ConcreteB, ConcreteA> {

   //constructor
}

@Entity
@Table
public class ConcreteB extends AbstractB<ConcreteA, ConcreteB>{

   //constructor
}

Caused by: org.hibernate.AnnotationException: Property package.ClassA.concreteA has an unbound type and no explicit target entity. Resolve this Generic usage issue or set an explicit target attribute (eg @OneToMany(target=) or use an explicit @Type