通过@ManagedProperty注入ResourceBundle似乎在@Named内部不起作用 [英] Injecting ResourceBundle via @ManagedProperty doesn't seem to work inside @Named

问题描述

如何从Java代码访问消息束以根据当前语言环境获取消息?

How can I access messages bundle from java code to get message according to current locale?

我尝试使用@ManagedProperty，如下所示:

I tried using @ManagedProperty like below:

@Named 
@SessionScoped 
public class UserBean implements Serializable {

    @ManagedProperty("#{msg}")
    private ResourceBundle bundle;

    // ...

    public void setBundle(ResourceBundle bundle) {
        this.bundle = bundle;
    }

}

但是，它仍然是null.似乎在@Named内不起作用.

However, it remains null. It seems that it doesn't work inside a @Named.

这是我在faces-context.xml中注册资源束的方式:

This is how I registered the resource bundle in faces-context.xml:

<application>

    <message-bundle>validator.messages</message-bundle>

    <locale-config>
        <supported-locale>en_US</supported-locale>
        <supported-locale>ua_UA</supported-locale>
    </locale-config>

    <resource-bundle>
        <base-name>lang.messages</base-name>
        <var>msg</var>
    </resource-bundle>

</application>

作者评论:

udated by author:

@BalusC我收到错误消息

@BalusC I get error

16:29:10,968 ERROR [org.apache.catalina.core.ContainerBase.[jboss.web].[default-host].[/WEBSearchPrime_JB_lang].[Faces Servlet]] (http-localhost-127.0.0.1-8080-1) Servlet.service() for servlet Faces Servlet threw exception: org.jboss.weld.exceptions.IllegalProductException: WELD-000054 Producers cannot produce non-serializable instances for injection into non-transient fields of passivating beans\\n\\nProducer\: Producer Method [PropertyResourceBundle] with qualifiers [@Any @Default] declared as [[method] @Produces public util.BundleProducer.getBundle()]\\nInjection Point\: [field] @Inject private model.UserBean.bundle

请注意，我还放置了Serializable接口

note, that I also put Serializable interface

推荐答案

您不能在CDI托管Bean中使用@ManagedProperty进行@Named注释.您只能按@ManagedBean注释在JSF托管bean中使用它.

You can't use @ManagedProperty in a CDI managed bean as annotated with @Named. You can only use it in a JSF managed bean as annotated with @ManagedBean.

CDI没有任何注解来插入像@ManagedProperty这样的EL表达式的评估结果. CDI方法是使用带有@Produces的"CDI生产者"，其中您返回具体类型，对于基于.properties文件的资源包，该类型为PropertyResourceBundle.

CDI doesn't have any annotations to inject the evaluation result of an EL expression like as @ManagedProperty. The CDI approach is using a "CDI producer" with @Produces wherein you return the concrete type, which is PropertyResourceBundle in case of .properties file based resource bundles.

只需将此类放在您的WAR中:

Just drop this class somewhere in your WAR:

@RequestScoped
public class BundleProducer {

    @Produces
    public PropertyResourceBundle getBundle() {
        FacesContext context = FacesContext.getCurrentInstance();
        return context.getApplication().evaluateExpressionGet(context, "#{msg}", PropertyResourceBundle.class);
    }

}

现在您可以按如下方式注入它:

Now you can inject it as below:

@Inject
private PropertyResourceBundle bundle;

这篇关于通过@ManagedProperty注入ResourceBundle似乎在@Named内部不起作用的文章就介绍到这了，希望我们推荐的答案对大家有所帮助，也希望大家多多支持IT屋！