Java Hibernate @OneToMany Criteria Projections返回NULL

Question

我有一对多关系所有者 - >狗.

我将通过ID查询狗以及以EAGER方式引入所有者我使用Hibernate 4.1.6设置此代码而不使用XML映射.我只需要来自DOG和OWNER的一些字段使用Projections Hibernate生成的SQL是完美的,但是我的对象没有填充,因为DOG返回填充的字段但是返回的所有者是 DOG.OWNER==NULL我到目前为止使用的代码...我的entities.other代码省略简洁

@Entity
public class Owner implements Serializable
{
    Set<Dog>dogs=new HashSet<Dogs>(0);
    @OneToMany(fetch=FetchType.LAZY, mappedBy="owner")
    public Set<Dogs> getDogs(){return this.dogs}    
}   

@Entity
public class Dog implements Serializable
{
    private Owner owner;    
    @ManyToOne(fetch=FetchType.LAZY)
    @JoinColumn(name="ownerid")
    public Owner getOwner(){return this.owner;}
 }  

这是我的方法.

public Dog getDogAndOwnerById(Integer dogId) 
{
    Projection p=Projections.projectionList()
    .add(Projections.property("d.id"),"id")
       .add(Projections.property("o.id"),"id");//and others fields
    Session session = getHibernateTemplate().getSessionFactory().openSession();        
    Criteria like = session.createCriteria(Dog.class,"d")
    .add(Restrictions.idEq(dogId)).setProjection(p)
    .setResultTransformer(Transformers.aliasToBean(Dog.class))
    .setFetchMode("owner",FetchMode.JOIN).createAlias("owner","o");        
    Dog dog = (Dog)like.uniqueResult();        
    //Object[]obj=(Object[])like.uniqueResult(); for(Object id:obj)System.out.println(id);
    //System.out.println(obj.length);
    session.close();
    return dog;
    //dog is OK BUT dog.OWNER is null.
}    

这里的查询很完美就是SQL

select
    this_.ID as y0_,
    owner_.ID as y1_ 
from
    dog this_ 
inner join
    owner owner_ 
        on this_.ownerid=owner_.ID 
where
    and this_.ID = ?    

我的问题是...狗实例不是空的,所有的字段都可以,同时Dog.Owner是returnig null我试过这个不使用任何变形金刚.

Object[]obj=(Object[])like.uniqueResult(); for(Object id:obj)System.out.println(id);
System.out.println(obj.length);

我可以看到数据正确Hibernate没有返回我的对象​​的权利吗？我做错了什么.

任何帮助都非常感激.

[更新]如果我使用这个

Projection p=Projections.projectionList()
.add(Projections.property("d.id"),"id")
.add(Projections.property("o.status"),"status");

和状态属于两个表,DOG实体填充另一个不是.

如果我使用

Projection p=Projections.projectionList()
.add(Projections.property("d.id"),"id")
.add(Projections.property("o.address"),"address");

和地址只属于所有者异常被抛出.

Exception in thread "main" org.hibernate.PropertyNotFoundException: 
Could not find setter for address on class com.generic.model.Dog

似乎Hibernate总是返回最大1实体填充它们不能将两个表[selected columns]填充到对象[selected objects]中？

Answer 1

我写了一个ResultTransformer,可以解决你的问题.它的名字是AliasToBeanNestedResultTransformer,请在github上查看.