在 Spring Beans 中使用 Session 范围

Question

我将 JSF 2 用于视图，将 Spring 用于业务逻辑。我正在尝试使用注释（@Scope（“session”））将会话范围设置为我的一个 spring bean，但我得到了这个异常：

    SEVERE: Context initialization failed
    org.springframework.beans.factory.BeanCreationException: Error creating bean with name 'handleFiles': Injection of autowired dependencies failed; nested exception is org.springframework.beans.factory.BeanCreationException: Could not autowire field: private creazione.util.FTPOperations creazione.components.HandleOldFiles.operations; 
nested exception is org.springframework.beans.factory.BeanCreationException: 
Error creating bean with name 'ftpOperations': Scope 'session' is not active for the current thread; consider defining a scoped proxy for this bean if you intend to refer to it from a singleton; 
nested exception is java.lang.IllegalStateException: No thread-bound request found: Are you referring to request attributes outside of an actual web request, or processing a request outside of the originally receiving thread? 
If you are actually operating within a web request and still receive this message, your code is probably running outside of DispatcherServlet/DispatcherPortlet: In this case, use RequestContextListener or RequestContextFilter to expose the current request.

我知道 RequestContextListener。它在我的 web.xml 中。我还添加了 RequestContextFilter：

<listener>
        <listener-class>
            org.springframework.web.context.ContextLoaderListener
        </listener-class>
    </listener>
    <listener>
        <listener-class>
            org.springframework.web.context.request.RequestContextListener
        </listener-class>
    </listener>

    <filter>
        <filter-name>requestContextFilter</filter-name>
        <filter-class>org.springframework.web.filter.RequestContextFilter</filter-class>
    </filter>

    <filter-mapping>
        <filter-name>requestContextFilter</filter-name>
        <url-pattern>/*</url-pattern>
        <dispatcher>REQUEST</dispatcher>
        <dispatcher>INCLUDE</dispatcher>
        <dispatcher>FORWARD</dispatcher>
    </filter-mapping>

似乎没有任何效果。我究竟做错了什么？ 谢谢！

Answer 1

如果您使用基于注释的配置，只需在您的主配置 xml 中更改此标记：

<context:component-scan base-package="my.package"/>

到

<context:component-scan base-package="my.package" scoped-proxy="targetClass" />

还可以通过注释标记类以使用代理：

@Component
@Scope(value = "session", proxyMode = ScopedProxyMode.TARGET_CLASS)

这对我有用。 更多细节在这里：4.12 Classpath scanning, managed components and writing configurations using Java

另外，如果您是通过上下文 xml 配置创建 bean，这里是这种情况的另一个示例：

<bean id="somebean" class="com.package.beans" scope="session">
    <aop:scoped-proxy/>
</bean>

Answer 2

尝试使用 aop:scoped-proxy 将必须注入的 bean 定义为会话。

<bean id="ftpOperations" class="..." scope="session">
    <aop:scoped-proxy/>
</bean>

如果还没有相关的命名空间，请添加：

<beans xmlns="http://www.springframework.org/schema/beans"
xmlns:aop="http://www.springframework.org/schema/aop"
    ...
xsi:schemaLocation="
        http://www.springframework.org/schema/aop 
        http://www.springframework.org/schema/aop/spring-aop-3.0.xsd
        ...