Java 泛型 "reverse relationship"(和 JPA)

Question

我有这两个类(class):

@Entity
public abstract class Compound {


    @OneToMany(fetch = FetchType.EAGER, mappedBy="compound",
        targetEntity=Containable.class, cascade = CascadeType.ALL)      
    private Set<Containable> containables = new HashSet<>();
}

@Entity 
public abstract class Containable {     

    @ManyToOne(optional=true, fetch = FetchType.EAGER, cascade = CascadeType.ALL)
    private Compound compound;
}

我想要以类型安全的方式实现的是，Compound 的特定实现仅接受 Containable 的特定实现，反之亦然。

我怎样才能实现这个目标？

编辑:

我已经从asenovm 得到了解决方案，只是想仔细检查它是否确实是正确的。

我的后续问题是，如果我有 class Compound<T extends Containable>和class Containable<T extends Compound> Containable 和Compound 是原始类型还是我弄错了？因为在 class Compound<T extends Containable> T 实际上是一个 Containable，而不是其他任何东西。

Answer 1

也许是这样的？

@Entity
public abstract class Compound<T extends Containable> {


    @OneToMany(fetch = FetchType.EAGER, mappedBy="compound",
        targetEntity=Containable.class, cascade = CascadeType.ALL)      
    private Set<T> containables = new HashSet<T>();

}

@Entity 
public abstract class Containable<T extends Compound> {     

    @ManyToOne(optional=true, fetch = FetchType.EAGER, cascade = CascadeType.ALL)
    private T compound;
}