`<?xml version="1.0" encoding="UTF-8"?>
<persistence version="2.1" xmlns="http://xmlns.jcp.org/xml/ns/persistence" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xsi:schemaLocation="http://xmlns.jcp.org/xml/ns/persistence http://xmlns.jcp.org/xml/ns/persistence/persistence_2_1.xsd">
  <persistence-unit name="ru.rgups.ui.testSys_JTest-ejb_ejb_1.0-SNAPSHOTPU" transaction-type="JTA">
    <jta-data-source>jdbc/__DbConn</jta-data-source
    <properties>
      <property name="eclipselink.ddl-generation" value="none"/>
      <property name="eclipselink.target-server" value="SunAS9"/>
      <property name="javax.persistence.jtaDataSource" value="jdbc/__PGDbConn"/>
      <property name="eclipselink.logging.level" value="FINE"/>
      <property name="eclipselink.logging.level.sql" value="FINE"/>
      <property name="eclipselink.logging.parameters" value="true"/>
    </properties>
  </persistence-unit>
</persistence>`

@Stateless
public class TryFacade extends AbstractFacade<Try> {
    @PersistenceContext(unitName = "JTest-ejb_1.0-SNAPSHOTPU")
    private EntityManager em;
    @EJB
    private TryQuestionFacade tryQuestionF;
    .
    .
    .
    @TransactionAttribute(TransactionAttributeType.SUPPORTS)
    public Try findByID(Integer studId) {
        try {
            if (studId != null) {
                Try sst = em.createNamedQuery("Try.findByIdz", Try.class)
                        .setParameter("idz", studId)
                        .getSingleResult();
                return sst;
            }
        } catch (Exception ex) {
            ex.printStackTrace(System.err);
        }
        return null;
    }
    .
    .
    .

@Named("tryController")
@SessionScoped
public class TryController implements Serializable {

    @EJB
    private TryFacade ejbFacade;

    .
    .
    .
    public Try getTryByIdz(Integer id) {
        if (id != null) {
            selected=getFacade().findByID(id);
            return getSelected();
        }
        return null;
    }

    .
    .
    .