Domanda

I have 2 entities connected through join annotations and everything works fine except for the query result which is strange.

So I have this class say Cat and the other class say Home. So if I execute a named query of the class Cat I expect it's property Cat.home to be populated with the query result from the table Home.

I'm executing the query this way:

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

and the result I get is:

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

So my question is how can I access those two objects Cat and Home, and how come I'm getting this result from the entity manager and not a single Object Cat where Home is in Cat.home

Entities:

Cat.java - Cat entity

//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 - Home entity

   @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;
    }
}

Thanks in advance!

È stato utile?

Soluzione

add select part to named query

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