Ebean EmbeddedId映射列到ManyToOne关系

为了解决这个问题，我们必须：

1. 将EntityB.entityA映射到与EntityB.ID.entityA_FK_ID相同的列
2. 设置EntityB.entityA @JoinColumn批注的’insertable’和’updateable’属性
3. EntityB.entityA的替代设置器

这是代码：

EntityA.java：

@Entity public class EntityA extends Model {    @Id    private String ID;    @oneToMany(mappedBy="entityA")    public List<EntityB> listEntitesB;    public static Finder<String,EntityA> find = new Finder<String,EntityA>(        String.class, EntityA.class    );    public EntityA() {        ID = UUID.randomUUID().toString();    }    public String getID() {        return ID;    }}

EntityB.java：

@Entity public class EntityB extends Model {    @EmbeddedId    private EntityB_PK ID;    @ManyToOne    @JoinColumn(name = "entityA_fk_id", insertable = false, updatable = false)    private EntityA entityA;    public EntityA getEntityA() {        return entityA;    }    public void setEntityA(EntityA aEntityA) {        entityA = aEntityA;        ID.entityA_FK_ID = aEntityA.getID();    }    public EntityB(String entityB_ID){         ID = new EntityB_PK(UUID.randomUUID().toString(), entityB_ID);    }    public String getID() {        return ID.entityB_ID;    }}

EntityB_PK.java：

@Embeddable public class EntityB_PK implements Serializable {    public String entityB_ID;    @Column(name="entityA_fk_id")    public String entityA_FK_ID;    public EntityB_PK(String entB_ID, String entA_FK_ID){       entityB_ID = entB_ID;       entityA_FK_ID = entA_FK_ID;    }    @Override    public int hashCode() {        return entityB_ID.length() + entityA_FK_ID.length();    }    @Override    public boolean equals(Object obj) {        if (this == obj)  return true;        EntityB_PK b = (EntityB_PK)obj;        if(b==null) return false;        if (b.entityB_ID.equals(entityB_ID) && b.entityA_FK_ID.equals(entityA_FK_ID)) { return true;        }        return false;    }}