Java – JPA: query to get the result according to the foreign key value defined in the entity class?

Netbean 6.9 generates the following JPA entity classes from this SQL Server 2008 table:

I want to get all productdescriptors with a specific SKU value Something like this:

SELECT * FROM ProductDescriptors WHERE SKU='something'

Given the entity class, what is the Java code to get the result?

thank you.

@Entity
@Table(name = "ProductDescriptors")
@NamedQueries({
    @NamedQuery(name = "ProductDescriptors.findAll",query = "SELECT p FROM ProductDescriptors p"),@NamedQuery(name = "ProductDescriptors.findByDescriptorID",query = "SELECT p FROM ProductDescriptors p WHERE p.descriptorID = :descriptorID"),@NamedQuery(name = "ProductDescriptors.findByLanguageCode",query = "SELECT p FROM ProductDescriptors p WHERE p.languageCode = :languageCode"),@NamedQuery(name = "ProductDescriptors.findByTitle",query = "SELECT p FROM ProductDescriptors p WHERE p.title = :title"),@NamedQuery(name = "ProductDescriptors.findByIsDefault",query = "SELECT p FROM ProductDescriptors p WHERE p.isDefault = :isDefault"),@NamedQuery(name = "ProductDescriptors.findByBody",query = "SELECT p FROM ProductDescriptors p WHERE p.body = :body")})
public class ProductDescriptors implements Serializable {
    private static final long serialVersionUID = 1L;
    @Id
    @Basic(optional = false)
    @Column(name = "DescriptorID")
    private Integer descriptorID;
    @Basic(optional = false)
    @Column(name = "LanguageCode")
    private String languageCode;
    @Basic(optional = false)
    @Column(name = "Title")
    private String title;
    @Basic(optional = false)
    @Column(name = "IsDefault")
    private boolean isDefault;
    @Basic(optional = false)
    @Column(name = "Body")
    private String body;
    @JoinColumn(name = "SKU",referencedColumnName = "SKU")
    @ManyToOne(optional = false)
    private Products products;

…

Solution

Something like this:

@PersistenceContext( unitName = "youPersistenceUnitHere" )
private EntityManager _entityManager;

public List<ProductDescriptors> getProductDescriptorsBySku( String sku ) {
   Query query = _entityManager.createQuery( "Select ProductDescriptors from ProductDescriptors pd where pd.products.sku = ?1" );
   query.setParameter( 1,sku );
   return new ArrayList<ProductDescriptors>( query.getResultList() );
}