为什么我不能捕获EJB异常？ [英] Why can't I catch EJB exceptions?

问题描述

在我的java ee 6项目中，我似乎无法捕获诸如NoResultException或EJBException之类的异常。有什么我做错了吗？我在EJB容器之外捕获了异常，但这是我第一次使用EJB。谢谢。

  @Stateless 
 public class UserEJB {
 
 @PersistenceContext 
实体管理器
 
 public String getUserName（User user）{
 return user.getName（）; 
} 
 
 public用户fetchUserByEmail（String email）{
 
用户user = em.createNamedQuery（User.findByEmail，User.class）.setParameter（电子邮件，电子邮件）.getSingleResult（）; 
返回用户; 
} 
 
 public用户fetchUserById（int id）{
返回em.createNamedQuery（User.findByUserId，User.class）.setParameter（userId，id）。 getSingleResult（）; 
} 
 
 public List< User> fetchAllUsers（）{
 return em.createNamedQuery（User.findAll，User.class）.getResultList（）; 
} 
} 
 
 @Named（value =userController）
 @RequestScoped 
 public class UserController {
 
 private User user = new User（）; 
 @EJB 
 UserEJB userEJB; 
 @Inject 
 SecurityController securityController; 
 
 public UserController（）{
} 
 
 public void login（ActionEvent event）{
 
 try {
 
用户userLogin = userEJB.fetchUserByEmail（user.getEmail（））; 
 
} catch（Exception e）{
 
} 
 
 if（userLogin.getPassword（）。equals（user.getPassword（）））{ 
 securityController.setIsLoggedIn（true）; 
 securityController.setIsAdmin（true）; 
 securityController.setUser（user）; 
} 
} 
 
 / ** 
 * @返回用户
 * / 
 public User getUser（）{
返回用户; 
} 
 
 / ** 
 * @param用户设置
 * / 
 public void setUser（User user）{
 this.user = user; 
} 
  

解决方案

.out.printlns在代码中？一个在异常处理程序中，一个在if语句之前。你得到什么？

看看代码我会说你将能够捕获异常，这应该是一个JPA异常包装在一个EJB中。 p>

I can't seem to catch exceptions such as NoResultException or EJBException in my java ee 6 project. Is there something I am doing wrong? I have caught exceptions outside the EJB container but this is my first time using EJB. Thanks.

@Stateless
public class UserEJB {

    @PersistenceContext
    EntityManager em;

    public String getUserName(User user) {
        return user.getName();
    }

    public User fetchUserByEmail(String email) {

        User user = em.createNamedQuery("User.findByEmail", User.class).setParameter("email", email).getSingleResult();
        return user;
    }

    public User fetchUserById(int id) {
        return em.createNamedQuery("User.findByUserId", User.class).setParameter("userId", id).getSingleResult();
    }

    public List<User> fetchAllUsers() {
        return em.createNamedQuery("User.findAll", User.class).getResultList();
    }
}

@Named(value = "userController")
@RequestScoped
public class UserController {

    private User user = new User();
    @EJB
    UserEJB userEJB;
    @Inject
    SecurityController securityController;

    public UserController() {
    }

    public void login(ActionEvent event) {

        try {

             User userLogin = userEJB.fetchUserByEmail(user.getEmail());

        } catch (Exception e) {

        }

        if (userLogin.getPassword().equals(user.getPassword())) {
            securityController.setIsLoggedIn(true);
            securityController.setIsAdmin(true);
            securityController.setUser(user);
        }
    }

    /**
     * @return the user
     */
    public User getUser() {
        return user;
    }

    /**
     * @param user the user to set
     */
    public void setUser(User user) {
        this.user = user;
    }

解决方案

What if you put two System.out.printlns in the code? One in the exception handler and one right before the if statement. What do you get?

Looking at the code I would say you would be able to catch the exception, which should be a JPA exception wrapped in an EJB one.

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