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铸豆 <?> 从BeanManager到Servlet中的类实例

[英]Cast Bean<?> from BeanManager to class instance in Servlet

我有一个EJB项目,并具有以下注释:

@Retention(RUNTIME)
@Target(TYPE)
@Qualifier
public @interface AfterComplete {
}

我有2个用此注释修饰的类。 他们也是@Stateless

@AfterComplete
@Stateless
public class AfterCompletePrinter implements IAfterComplete {

  public void afterComplete(String someValue) {
    System.out.println("After complete printer: " + someValue);
  }

}


@AfterComplete
@Stateless
public class AfterCompleteErrPrinter implements IAfterComplete{

  public void afterComplete(String someValue) {
    System.err.println(someValue);
  }
}

在servlet中,我有:

@WebServlet("/")
public class DemoServlet extends HttpServlet {
  @Inject
  BeanManager beanManager;

  @Override
  protected void doGet(HttpServletRequest request, HttpServletResponse response)
      throws ServletException, IOException {
    Set<Bean<?>> beans = beanManager
        .getBeans(Object.class,new AnnotationLiteral<AfterComplete>() {});

    for (Bean<?> bean : beans) {
      response.getWriter().print(bean.getBeanClass());
      // IAfterComplete iac = (IAfterComplete) bean;
    }
  }
}

我的servlet打印:

net.mikeski.ejb_annotations.AfterCompletePrinter类net.mikeski.ejb_annotations.AfterCompleteErrPrinter

但是,如果不加注释,此行将引发异常:

IAfterComplete iac =(IAfterComplete)bean;

例外是:

java.lang.ClassCastException:org.jboss.weld.bean.SessionBean无法转换为net.mikeski.ejb_annotations.IAfterComplete

我如何使用bean来执行IAfterComplete的类的实例? bean.getName()返回null。

我在想是否可以得到它的JNDI名称,所以可以进行查找,但是看不到该怎么做。

如果有任何不同,则为Wildfly 10。

因此,我找到了有效的答案,它是这样完成的:

@Override
  protected void doGet(HttpServletRequest request, HttpServletResponse response)
      throws ServletException, IOException {
    Set<Bean<?>> beans = beanManager
        .getBeans(Object.class, new AnnotationLiteral<AfterComplete>() {
        });

    for (Bean<?> bean : beans) {
      response.getWriter().print(bean.getBeanClass());
      IAfterComplete iac = (IAfterComplete) beanManager.getReference(bean, IAfterComplete.class, beanManager.createCreationalContext(bean));
      iac.afterComplete("After complete called on " + iac);
    }
  }

我将整个工作项目放在这里的github上: https : //github.com/mikebski/ejb-custom-annotations

这是一篇简短的博客文章,其中包含一些解释:

http://blog.mikeski.net/blog_post/487

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