JPA休眠SQL查询

Question

Hey i have problem with JPA hibernate SQL query where i serach a elements from one basic attribute and one which is in the basic entity in the List. so i have to compare with array string, beacause i using a multitype search. my JPA one is:

@Entity
  public class Dejavnosti implements Serializable {
private static final long serialVersionUID = 1L;

@Id
@GeneratedValue(strategy=GenerationType.IDENTITY)
@Column(name="id_dejavnosti")
private int idDejavnosti;
    private String naziv;



//bi-directional many-to-one association to Lokacija
@ManyToOne
private Lokacija lokacija;

//bi-directional many-to-many association to Produkti
@ManyToMany
@JoinTable(
    name="dejavnosti_produkti"
    , joinColumns={
        @JoinColumn(name="dejavnosti_id_dejavnosti")
        }
    , inverseJoinColumns={
        @JoinColumn(name="produkti_id_produkti")
        }
    )
private List<Produkti> produktis;

And second:

@Entity
    public class Produkti implements Serializable {
private static final long serialVersionUID = 1L;

@Id
@GeneratedValue(strategy=GenerationType.IDENTITY)
@Column(name="id_produkti")
private int idProdukti;

    private String naziv;

//bi-directional many-to-many association to Dejavnosti
@ManyToMany(mappedBy="produktis")
private List<Dejavnosti> dejavnostis;

and this is my method in EJB which have input List searchwords to compare with 2 attributes one is Dejavnosti.naziv and second Dejavnosti.produktis.naziv:

public List<Dejavnosti> Isci(List<String> selectedTexts){

            String klic="SELECT c FROM Dejavnosti c INNER JOIN c.produktis dp WHERE  "  ;

                for(int i=0;i<selectedTexts.size();i++){
                klic=klic+"c.naziv LIKE '%" +selectedTexts.get(i) + "%'  OR ";
                klic=klic+"dp.naziv LIKE '%" +selectedTexts.get(i) + "%'  ";
                //zadnjič ne doda OR
                if(!(i+1==selectedTexts.size())){
                    klic=klic+" OR ";
                }



                }


        List<Dejavnosti> dejavnosti=em.createQuery(klic,Dejavnosti.class).getResultList();


        return dejavnosti;

    }

I don't have errors but sql doesn't work, beacuse return 0 elements but the elemenets are in! i know its a bad code in method but this is my idea :) Thanks for help and to improve my knowledge.

Answer 1

Since you've already defined your many-to-many relationship in your entities, there's no need to call out the join in you query again.

You would change your query to something like this

SELECT c FROM Dejavnosti WHERE c.produktis.naziv LIKE ? OR c.naziv LIKE ?