JPA 調用元件〈EJB〉
package com.emprogria.jpa;
import com.emprogria.jpa.CdrInfoPK;
import com.emprogria.exceptions.NonexistentEntityException;
import com.emprogria.exceptions.PreexistingEntityException;
import java.util.List;
import javax.persistence.EntityManager;
import javax.persistence.EntityManagerFactory;
import javax.persistence.Persistence;
import javax.persistence.Query;
import javax.persistence.EntityNotFoundException;
public class CdrInfoJpaController {
public CdrInfoJpaController() {
emf = Persistence.createEntityManagerFactory("CDR-Tasks-ejbPU");
}
private EntityManagerFactory emf = null;
public EntityManager getEntityManager() {
return emf.createEntityManager();
}
public void create(CdrInfo cdrInfo) throws PreexistingEntityException, Exception {
if (cdrInfo.getCdrInfoPK() == null) {
cdrInfo.setCdrInfoPK(new CdrInfoPK());
}
EntityManager em = null;
try {
em = getEntityManager();
// em.getTransaction().begin();
em.persist(cdrInfo);
// em.getTransaction().commit();
} catch (Exception ex) {
if (findCdrInfo(cdrInfo.getCdrInfoPK()) != null) {
throw new PreexistingEntityException("物件 " + cdrInfo + " 已存在!", ex);
}
throw ex;
} finally {
if (em != null) {
em.close();
}
}
}
public void edit(CdrInfo cdrInfo) throws NonexistentEntityException, Exception {
EntityManager em = null;
try {
em = getEntityManager();
em.getTransaction().begin();
cdrInfo = em.merge(cdrInfo);
em.getTransaction().commit();
} catch (Exception ex) {
String msg = ex.getLocalizedMessage();
if (msg == null || msg.length() == 0) {
CdrInfoPK id = cdrInfo.getCdrInfoPK();
if (findCdrInfo(id) == null) {
throw new NonexistentEntityException("主鍵 " + id + " 不存在!");
}
}
throw ex;
} finally {
if (em != null) {
em.close();
}
}
}
public void destroy(CdrInfoPK id) throws NonexistentEntityException {
EntityManager em = null;
try {
em = getEntityManager();
em.getTransaction().begin();
CdrInfo cdrInfo;
try {
cdrInfo = em.getReference(CdrInfo.class, id);
cdrInfo.getCdrInfoPK();
} catch (EntityNotFoundException enfe) {
throw new NonexistentEntityException("主鍵 " + id + " 不存在!", enfe);
}
em.remove(cdrInfo);
em.getTransaction().commit();
} finally {
if (em != null) {
em.close();
}
}
}
public List<CdrInfo> findCdrInfoEntities() {
return findCdrInfoEntities(true, -1, -1);
}
public List<CdrInfo> findCdrInfoEntities(int maxResults, int firstResult) {
return findCdrInfoEntities(false, maxResults, firstResult);
}
private List<CdrInfo> findCdrInfoEntities(boolean all, int maxResults, int firstResult) {
EntityManager em = getEntityManager();
try {
Query q = em.createQuery("select object(o) from CdrInfo as o");
if (!all) {
q.setMaxResults(maxResults);
q.setFirstResult(firstResult);
}
return q.getResultList();
} finally {
em.close();
}
}
public CdrInfo findCdrInfo(CdrInfoPK id) {
EntityManager em = getEntityManager();
try {
return em.find(CdrInfo.class, id);
} finally {
em.close();
}
}
public int getCdrInfoCount() {
EntityManager em = getEntityManager();
try {
Query q = em.createQuery("select count(o) from CdrInfo as o");
return ((Long) q.getSingleResult()).intValue();
} finally {
em.close();
}
}
}