如何使用 Entitymanager (Hibernate) 將我從列表中獲取的數據插入到數據庫中？

Question

我有一個列表，我想添加以將從列表中獲取的數據添加到數據庫中。 我的代碼是：

List<EventPayload> mylist=eventpojo.getEventPayload();

            for(EventPayload array : mylist)
            {
                System.out.println("Comment Text :"+array.getCommentText());
                System.out.println("Comment Type :"+array.getCommentType());
                System.out.println("Comment Id :"+array.getCommentId());
                System.out.println("Email id :"+array.getComment_email());
                String email1=array.getComment_email();
                EntityManagerFactory entityManagerFactory = Persistence.createEntityManagerFactory("jcg-JPA");
                EntityManager em = entityManagerFactory.createEntityManager();


                List email=em.createQuery("SELECT usrinfo.user_id FROM UserInfo usrinfo WHERE usrinfo.email_id = :id").setParameter("id", email1).getResultList();
                String userid=email.get(0).toString();
                System.out.println("User id:"+userid);
                Date date = new Date();
                PageInfo pageinfo=new PageInfo();
                pageinfo.setComment_id(array.getCommentId());
                pageinfo.setComment_text(array.getCommentText());
                pageinfo.setComment_type(array.getCommentType());
                String date1=sdf.format(date);
                pageinfo.setCreation_date(sdf.parse(date1));
                pageinfo.setModification_date(sdf.parse(date1));
                pageinfo.setRetrospective_id(eventpojo.getEventRetrospectiveId());
                int user_id = Integer.parseInt(userid);
                pageinfo.setUser_id(user_id);
                em.persist(pageinfo);

                }

我都用POJO的映射表和它的工作fine.I只是想添加CommentText Comment type comment Id Email Id Creation Date Modification date和RetrospectiveID 。我有一個表PAGEINFO，也是一個名為PageInfo這些7個領域POJO .請幫助

Answer 1

在事務中運行持久代碼。

List<EventPayload> mylist=eventpojo.getEventPayload();
        EntityManagerFactory entityManagerFactory = Persistence.createEntityManagerFactory("jcg-JPA");

        for(EventPayload array : mylist)
        {
            System.out.println("Comment Text :"+array.getCommentText());
            System.out.println("Comment Type :"+array.getCommentType());
            System.out.println("Comment Id :"+array.getCommentId());
            System.out.println("Email id :"+array.getComment_email());
            String email1=array.getComment_email();

            EntityManager em = entityManagerFactory.createEntityManager();


            List email=em.createQuery("SELECT usrinfo.user_id FROM UserInfo usrinfo WHERE usrinfo.email_id = :id").setParameter("id", email1).getResultList();
            String userid=email.get(0).toString();
            System.out.println("User id:"+userid);
            Date date = new Date();
            PageInfo pageinfo=new PageInfo();
            pageinfo.setComment_id(array.getCommentId());
            pageinfo.setComment_text(array.getCommentText());
            pageinfo.setComment_type(array.getCommentType());
            String date1=sdf.format(date);
            pageinfo.setCreation_date(sdf.parse(date1));
            pageinfo.setModification_date(sdf.parse(date1));
            pageinfo.setRetrospective_id(eventpojo.getEventRetrospectiveId());
            int user_id = Integer.parseInt(userid);
            pageinfo.setUser_id(user_id);
            EntityTransaction  trans= entityManager.getTransaction();


            trans.begin();

            em.persist(pageinfo);

            trans.commit();
            em.close();

            }

        entityManagerFactory.close();