为什么我的@ApplicationScope CDI bean没有更新? [英] Why my @ApplicationScope CDI bean not updated?

问题描述

在我的应用程序中，我有一个@ApplicationScoped CDI bean，用于存储数据库中的一些信息:

In my application, I have an @ApplicationScoped CDI bean to store some information from the database:

@Named
@ApplicationScoped
public class MrBean {
   @EJB
   private SoyaBean soyaBean;
   private List<Toys> myToys;

   @PostConstruct
   public void prepareMrBean() {
      this.myToys = soyaBean.getToys();
   }

   public void updateToys() {
      this.myToys = soyaBean.getToys();
   }
}

我也有一个AddToy.xhtml页面，可以简单地将一个玩具添加到数据库中.支持bean如下:

I also have a AddToy.xhtml page which would simply add a toy to the database. The backing bean is as following:

@Named
@RequestScoped
public class MrsBean {
   @EJB
   private SoyaBean soyaBean;
   @Inject
   private MrBean mrBean;

   public void addToy() {
      this.soyaBean.addToy();
      this.mrBean.updateToys();
   }
}

由于数据库中添加了一个新玩具，因此我想更新mrBean中的玩具列表.但是，即使mrsBean称为mrBean.updateToys()，mrBean中的玩具列表也不会被更新.我还有另一个ViewToys.xhtml，它带有一个@RequestScoped备用bean来查看玩具列表，但我没有看到该列表得到更新.

Since there is a new toy added to the database, I wanted to update the list of toys in mrBean. However, even though mrsBean called mrBean.updateToys(), the list of toys in mrBean is not updated at all. I have another ViewToys.xhtml with a @RequestScoped backing bean to view the list of toys and I didn't see the list get updated.

如果有人能给我有关如何解决此问题的建议，我将不胜感激.

I'd be very grateful if someone could give me an advice on how to tackle this problem.

更新:这是我的SoyaBean实现:

UPDATE: This is my SoyaBean implementation:

@Stateless
public class SoyaBeanImpl implements SoyaBean {
   @PersistenceContext()
   private EntityManager em;

   @Override
   public List<Toys> getToys() {
      Query q = em.createQuery("SELECT T from Toys T");
      return (List<Toys>) q.getResultList();
   }

   @Override
   public void addToy() {
      Toys newToy = new Toys();
      em.persist(newToy);
   }
}

更新2 如果有人能向我展示如何以除烦恼之外的其他方式实现同​​一目标，我也将非常感谢.

UPDATE 2 I'd also really appreciate if someone could show me how I can achieve the same goal in any ways other than my troubling way.

最诚挚的问候，

詹姆斯·特兰

推荐答案

问题是所有SQL查询的结果都已缓存.因此，即使我尝试刷新玩具列表，也只能收到旧结果.我通过将文件persistence.xml中的选项Shared Cache Mode设置为None解决了此问题.

The problem was that the results of all SQL queries were cached. Hence, even though I tried to refresh the list of toys, it only received the old result. I solved this problem by setting the option Shared Cache Mode in the file persistence.xml to None.

我认为完全不使用缓存不是一个好的选择.因此，如果有人可以告诉我如何在无需关闭缓存的情况下达到相同的效果，我将不胜感激.

I believe not using cache at all is not a good option. Hence, I'd be very grateful if someone could show me how I can achieve the same result without having to turn off cache.

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