EnityManager查询返回一个奇怪的无法访问的对象

Question

我有2个实体通过连接注释连接，一切正常，除了奇怪的查询结果。

所以我有这个班级说猫和其他班级说首页。因此，如果我执行类Cat的命名查询，我期望它的属性Cat.home将填充来自表主页的查询结果。

我执行的查询是这样的：

List<Cat> a = (List<Cat>) em.createNamedQuery("Cat.findHome") 
      .setParameter("catName", catName) 
      .setParameter("houseKey", houseKey).getResultList(); 

，结果我得到的是：

a = ArrayList<E> 
     elementData= Object[10] (id=22688) 
      [0] = Object[2] (id=22692) 
       [0] = Cat (id=22692) 
       [1] = Home (id=22692) 
      [1] = null 
      [2] = null 
      [3] = null 
      [4] = null 
      [5] = null 
      ... 
      [9] = null 

所以我的问题是我如何可以访问这些两个对象猫和主页，以及我如何从实体管理器获取此结果而不是单个对象Cat其中首页是Cat.home

实体：

Cat.java - 猫实体

//imports here 

@Entity 
@Table(name="CAT") 
@NamedQuery(name="cat.findHome", 
     query="from Cat a join a.home p where a.name = :catName and p.housekey like :houseKey") 
public class Cat implements Serializable{ 

private static final long serialVersionUID = 1L; 
private String catkey; 
private String name; 

public List<Home> key; // a cat can have many homes 

/** 
* @param catkey the catkey to set 
*/ 
public void setCatkey(String catkey) { 
    this.catkey = catkey; 
} 

/** 
* @return the catkey 
*/ 
@Id 
@Column(name="K_CAT") 
public String getCatkey() { 
    return catkey; 
} 

/** 
* @return the name 
*/ 
@Column(name="NAME") 
public String getName() { 
    return name; 
} 

/** 
* @param name the name to set 
*/ 
public void setName(String name) { 
    this.name = name; 
} 

/** 
* @param home the home to set 
*/ 
public void setHome(List<Home> home) { 
    this.home = home; 
} 

/** 
* @return the home 
*/ 
@OneToMany(cascade=CascadeType.ALL, fetch=FetchType.LAZY, mappedBy="cat") 
@Filter(name="contrFilter",condition = "K_CAT=:kcathome") 
public List<Home> getHome() { 
     return home; 
    } 
} 

Home.java - 首页实体

@Entity 
@Table(name="HOME") 
public class Home implements Serializable{ 

    private static final long serialVersionUID = 1L; 

private Sting housekey; 
private Cat cat; 

/** 
* @param housekey the housekey to set 
*/ 
public void setHousekey(String housekey) { 
    this.housekey = housekey; 
} 

/** 
* @return the housekey 
*/ 
@Id 
@Column(name="K_HOME") 
public String getHousekey(){ 
    return housekey; 
} 

/** 
* @param cat the cat to set 
*/ 
public void setCat(Cat cat) { 
    this.cat = cat; 
} 

/** 
* @return the cat 
*/ 
@ManyToOne(fetch = FetchType.LAZY) 
@JoinColumn(name = "K_CAT_HOME", updatable=false, insertable=false) 
public Cat getCat() { 
     return cat; 
    } 
} 

提前感谢！

Answer 1

添加select部分命名查询

query="select a from Cat a where a.name = :catName and a.home.houseKey like :houseKey")