JPA service里面的两个文件
package com.hunqing.user.service;import com.hunqing.user.entity.User;/** * 用户操作接口 * * @author * * <p>Modification History:</p> * <p>Date Author Description</p> * <p>------------------------------------------------------------------</p> * <p> </p> * <p> </p> */public interface IUserService { /** * Save. * * @param user the user */ public void save(User user); /** * Delete. * * @param String userName */ public void delete(String userName); /** * Update. * * @param user the user */ public void update(User user); /** * Find. * * @param user the user */ public User find(String userName);}package com.hunqing.user.service;import javax.persistence.EntityManager;import javax.persistence.PersistenceContext;import org.springframework.stereotype.Service;import org.springframework.transaction.annotation.Transactional;import com.hunqing.user.entity.User;@Service @Transactionalpublic class UserService implements IUserService { @PersistenceContext EntityManager em; public void delete(String userName) { //throws XXX //抛出的例外叫用户例外，客户端捕获 //运行期的异常叫运行期例外 spring会捕获运行期例外，自动回滚事物 //客户例外不会回滚事物 em.remove(em.getReference(User.class, userName)); } public User find(String userName) { return em.find(User.class,userName); } public void save(User user) { em.persist(user); } public void update(User user) { em.merge(user); }}TAG:
