将JSF管理Bean注入EJB [英] Injecting JSF Managed Bean to a EJB
问题描述
不,这是不可能的。 @ManagedProperty
仅适用于 @ManagedBean
类(JSF托管bean)。您只能使用 @EJB
或 @Inject
注入另一个EJB或CDI托管bean($ @Named
类)。
然而,在像EJB这样的业务服务类中,将前端类(如JSF或CDI托管的bean)插入到业务服务类中,使设计技术上没有任何意义。应该设计一个EJB,使其无变化可以重复使用在一个完全不同的前端,如JAX-RS webservice,甚至是一个简单的vanilla servlet。 EJB绝对不应该有任何 javax.faces。*
import / dependencies(就像它不应该有任何 javax.ws.rs。*
或 javax.servlet。*
one)。
如果您打算传递数据从JSF托管的bean到一个EJB,然后将它作为method参数传递。这样的数据通常是JPA @Entity
或至少一个返回一个实体的ID /关键字的风格。
Is is possible to inject JSF Managed Bean into an EJB? I have injected JSF Managed Beans in to another JSF Managed Bean as a @ManagedProperty. But when I do the same to the EJB, I get a null point exception.
No, that's not possible. The @ManagedProperty
works inside @ManagedBean
classes (JSF managed beans) only. You can only use @EJB
or @Inject
to inject another EJB or a CDI managed bean (a @Named
class).
However, it makes design technically no sense to inject a front-end class like a JSF or CDI managed bean in a business service class like an EJB. An EJB should be designed in such way that it can without changes be reused together a completely different front-end like JAX-RS webservice or even a plain vanilla servlet. An EJB should absolutely not have any javax.faces.*
imports/dependencies (like as that it should not have any javax.ws.rs.*
nor javax.servlet.*
ones).
If you intend to pass data from the JSF managed bean to an EJB, then just pass it as method argument. Such data is usually in flavor of a JPA @Entity
or at least an ID/keyword which returns an entity.
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