JBoss Seam：注入到POJO中的组件，而不是Session Bean [英] JBoss Seam: components injected into POJOs, but not Session Beans

问题描述

  @Name（authentator）
我有一个Seam组件来处理登录，名称为authentator 
 public class AuthenticatorAction implements Authenticator 
 {
 @PersistenceContext 
 private EntityManager em; 
 
 @In（required = false）
 @Out（required = false，scope = SESSION）
 private用户; 
 
 public boolean authenticate（）{...} 
 
} 
  

这样做很好，Seam注入了EntityManager实例。但是，一旦添加 @Stateless 注释，就不会发生任何注入！在这种情况下，EntityManager实例在进入 authenticate（）方法时为空。另一个有趣的注意事项是，使用一个单独的有状态会话bean，我在该类中的Logger实例只有在静态时才会被注入。如果我有非静态，它不会被注入。对于记录器来说，这是非常好的，但是对于这样的无状态会话bean，我显然不能使用这些组件的静态成员变量。

我感到困惑，因为这个认证器是准确地说，在Seam的预订范例中：注入一个私有成员变量的无状态会话bean。

任何想法？

解决方案

我很好奇：

然而，添加@Stateless注释，没有注射发生！

所以我希望你的使用@ javax.ejb.Local或@ javax.ejb.Remote将Authenticator界面标记为。如果没有，那么你的无状态将无法正常工作。

当你有一个@Stateless Session bean时，你必须激活一个Seam拦截器命令启用@ In-jection。像

  pureCharger-jar.jar 
 META-INF 
 ejb-jar.xml 
 persistence.xml 
  

ejb-jar.xml如下所示

 <？xml version =1.0encoding =UTF-8？> 
< ejb-jar xmlns =http://java.sun.com/xml/ns/javaeexmlns：xsi =http://www.w3.org/2001/XMLSchema-instancexsi ：schemaLocation =http://java.sun.com/xml/ns/javaee http://java.sun.com/xml/ns/javaee/ejb-jar_3_0.xsdversion =3.0> 
< interceptors> 
<拦截器> 
< interceptor-class> org.jboss.seam.ejb.SeamInterceptor< / interceptor-class> 
< / interceptor> 
< / interceptors> 
< assembly-descriptor> 
<拦截器绑定> 
< ejb-name> *< / ejb-name> 
< interceptor-class> org.jboss.seam.ejb.SeamInterceptor< / interceptor-class> 
< / interceptor-binding> 
< / assembly-descriptor> 
< / ejb-jar> 
  

如果可能，请查看 Seam Security with Dan Allen ，在JavaOne，Seam in Action书籍的作者。

问候，

I have a Seam component that handles login, with the name "authenticator":

@Name("authenticator")
public class AuthenticatorAction implements Authenticator
{
    @PersistenceContext 
    private EntityManager em;

    @In(required=false)   
    @Out(required=false, scope = SESSION)
    private User user;

    public boolean authenticate(){ ... }

}

This works just fine, Seam injects the EntityManager instance. However, as soon as I add the @Stateless annotation, none of the injection happens! In this case, the EntityManager instance is null upon entry to the authenticate() method. Another interesting note is that with a separate stateful session bean I have, the Logger instance in that class is only injected if I make it static. If i have it non-static, it is not injected. Thats fine for the logger, but for stateless session beans like that, I obviously can't have static member variables for these components.

I'm confused because this authenticator is exactly how it is in the Seam booking example: a stateless session bean with a private member variable being injected.

Any ideas?

解决方案

I am curious:

However, as soon as I add the @Stateless annotation, none of the injection happens!

So i hope your Authenticator interface is marked with @javax.ejb.Local or @javax.ejb.Remote. If not, so your Stateless will not work as expected.

When you have a @Stateless Session bean, you must activate a Seam interceptor in order to enable @In-jection. Something like

pureCharger-jar.jar 
    META-INF
        ejb-jar.xml
        persistence.xml

ejb-jar.xml is shown as follows

<?xml version="1.0" encoding="UTF-8"?>
<ejb-jar xmlns="http://java.sun.com/xml/ns/javaee" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xsi:schemaLocation="http://java.sun.com/xml/ns/javaee http://java.sun.com/xml/ns/javaee/ejb-jar_3_0.xsd" version="3.0">
    <interceptors>
        <interceptor>
            <interceptor-class>org.jboss.seam.ejb.SeamInterceptor</interceptor-class>
        </interceptor>
    </interceptors>
    <assembly-descriptor>
        <interceptor-binding>
            <ejb-name>*</ejb-name>
            <interceptor-class>org.jboss.seam.ejb.SeamInterceptor</interceptor-class>
        </interceptor-binding>
    </assembly-descriptor>
</ejb-jar>

If possible, take a look at Seam Security with Dan Allen, at JavaOne, author of Seam in Action book.

regards,

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