java JPA不持久化对象J2EE

Question

我有一个使用JEE5的遗留应用程序，我添加了一个类“People”，并在数据库中添加了很多记录（People只有peopleid和字符串peopledesc）

如果我使用getAllPeople（）方法正确填充列表，则所有数据都在那里

但是当我试图通过使用persistPeople（People-pep）的代码来持久化一个新记录时，它什么也做不了

系统。出来println显示添加到对象的描述，以便将新创建的对象传递给该方法，但不会在数据库中持久化：(

控制台输出中未显示任何错误

人们。爪哇

@Entity
public class People implements Serializable {

    @Id
    @GeneratedValue(strategy = GenerationType.IDENTITY)
    private int idpeople;

    private String desc;

坚持。xml

<persistence-unit name="PersistenceUnit" transaction-type="RESOURCE_LOCAL">
    <provider>org.hibernate.ejb.HibernatePersistence</provider>
    <class>entities.People</class>

PeopleDAOImPL.JAVA 

import javax.ejb.Stateless;
import javax.persistence.EntityManager;
import javax.persistence.EntityManagerFactory;
import javax.persistence.EntityTransaction;
import javax.persistence.Persistence;
import javax.persistence.PersistenceContext;
import javax.persistence.PersistenceUnit;
import residencias.dominio.Renovacion;


@Stateless
public class PeopleDAOImpl implements PeopleDAO {


   //EntityManagerFactory emf = Persistence.createEntityManagerFactory("PersistenceUnit");


    @PersistenceUnit(unitName="PersistenceUnit")
    private EntityManagerFactory emf;


    @Override
    public void persistPeople(People pep) {
        EntityManager em = emf.createEntityManager();

        System.out.println("description is  :"+pep.getDesc());
        em.persist(pep);


    }


    @Override
    public List<People> getAllPeople() {



        EntityManager em = emf.createEntityManager();
        List<People> results = new ArrayList();
        Query queryPrincipal;

        try {


            queryPrincipal = em.createQuery("SELECT p FROM People p");




            results = queryPrincipal.getResultList();

            return results;

        } catch (Exception e) {
            System.out.println(results.size());
            return results;

        } finally {
            if (em != null) {
                emf.close();
                em.close();
            }
        }

    }

Answer 1

虽然在调用查询期间，您不必在事务中运行，但当您尝试持久化/更新实体的状态时，您必须在事务边界内运行该特定操作

在您的情况下，可以使用以下配置：

@Stateless
@TransactionManagement(TransactionManagementType.CONTAINER)
public class PeopleDAOImpl implements PeopleDAO {

    @PersistenceUnit(unitName="PersistenceUnit")
    private EntityManagerFactory emf;

    @Override
    @TransactionAttribute(TransactionAttributeType.REQUIRED)
    public void persistPeople(People pep) {
        EntityManager em = emf.createEntityManager();

        System.out.println("description is  :"+pep.getDesc());
        em.persist(pep);


    }