如何在Hibernate中设置外键实体

Question

// this is GroupEntity
// mapping bond_id from Bond table
   @OneToMany(cascade = CascadeType.ALL)
    @JoinColumn(name ="bond_id")
    private BondEntity bondEntity;

BondEntity bondEntity = new BondEntity();
bondEntity.setBondId(1234); //remaining field of bondEntity not set
groupEntity.setBondEntity(bondEntity);

如果我继续尝试持久化这个实体，我将得到分离的实体传递到hibernate中持久化。

做这件事的正确方法是什么。可能是我理解的不对。

Answer 1

这是不正确的

@OneToMany(cascade = CascadeType.ALL)
@JoinColumn(name ="bond_id")
private BondEntity bondEntity;

也许你想用

@ManyToOne
@JoinColumn(name ="bond_id")
private BondEntity bondEntity;

请读一下这个

BondEntity bondEntity = new BondEntity();
bondEntity.setBondId(1234); //remaining field of bondEntity not set
groupEntity.setBondEntity(bondEntity);