2

我是 JSF 的新手，我想将我的网页国际化，这样网站访问者就可以通过单击代表每个区域设置的标志图标在语言之间切换。我编辑了 faces-config.xml 并添加了资源包、默认语言环境和支持的语言环境。然后我写了一个名为 changeLang.java 的 bean，它应该是用来做后台工作的。当页面被评估时，我收到以下错误：

index.xhtml @8,89 locale="#{changeLang.currentLocale}" Attribute did not evaluate to a String or Locale: null

技术：
JSF 2.0 Mojarra 2.0.2
Spring 3.0.0
Facelets

我的
changeLang.java 文件



package gui;

import java.io.Serializable;
import java.util.ArrayList;
import java.util.Iterator;
import java.util.Locale;
import javax.annotation.ManagedBean;
import javax.faces.context.FacesContext;
import org.springframework.context.annotation.Scope;

@ManagedBean
@Scope("session")

public class ChangeLang {
    private Locale currentLocale;

    public ChangeLang() {
           this.currentLocale = FacesContext.getCurrentInstance().getApplication().getDefaultLocale();
    }
    public Locale getCurrentLocale() {
        return this.currentLocale;
    }
    public ArrayList getSupportedLocales(){
        ArrayList listOfSupp = new ArrayList();
        Iterator locales = FacesContext.getCurrentInstance().getApplication().getSupportedLocales();
        while(locales.hasNext()) {
            Locale locale = locales.next();
            listOfSupp.add(locale);
        }

    return listOfSupp;
    }
    public void setCurrentLocaleLanguage(String language) {
        FacesContext.getCurrentInstance().getViewRoot().setLocale(new Locale(language));
    }
}

和“使用页面”片段

 
f:view locale="#{changeLang.currentLocale}" contentType="text/html; charset=utf-8"

完整日志：


An Error Occurred:
/index.xhtml @8,89 locale="#{changeLang.currentLocale}" Attribute did not evaluate to a String or Locale: null
- Stack Trace
javax.faces.view.facelets.TagAttributeException: /index.xhtml @8,89 locale="#{changeLang.currentLocale}" Attribute did not evaluate to a String or Locale: null
    at com.sun.faces.facelets.tag.jsf.ComponentSupport.getLocale(ComponentSupport.java:218)
    at com.sun.faces.facelets.tag.jsf.core.ViewHandler.apply(ViewHandler.java:119)
    at com.sun.faces.facelets.tag.ui.CompositionHandler.apply(CompositionHandler.java:160)
    at com.sun.faces.facelets.compiler.NamespaceHandler.apply(NamespaceHandler.java:86)
    at com.sun.faces.facelets.compiler.EncodingHandler.apply(EncodingHandler.java:75)
    at com.sun.faces.facelets.impl.DefaultFacelet.apply(DefaultFacelet.java:145)
    at com.sun.faces.application.view.FaceletViewHandlingStrategy.buildView(FaceletViewHandlingStrategy.java:716)
    at com.sun.faces.lifecycle.RenderResponsePhase.execute(RenderResponsePhase.java:106)
    at com.sun.faces.lifecycle.Phase.doPhase(Phase.java:101)
    at com.sun.faces.lifecycle.LifecycleImpl.render(LifecycleImpl.java:139)
    at javax.faces.webapp.FacesServlet.service(FacesServlet.java:313)
    at org.apache.catalina.core.StandardWrapper.service(StandardWrapper.java:1523)
    at org.apache.catalina.core.StandardWrapperValve.invoke(StandardWrapperValve.java:279)
    at org.apache.catalina.core.StandardContextValve.invoke(StandardContextValve.java:188)
    at org.apache.catalina.core.StandardPipeline.invoke(StandardPipeline.java:641)
    at com.sun.enterprise.web.WebPipeline.invoke(WebPipeline.java:97)
    at com.sun.enterprise.web.PESessionLockingStandardPipeline.invoke(PESessionLockingStandardPipeline.java:85)
    at org.apache.catalina.core.StandardHostValve.invoke(StandardHostValve.java:185)
    at org.apache.catalina.connector.CoyoteAdapter.doService(CoyoteAdapter.java:332)
    at org.apache.catalina.connector.CoyoteAdapter.service(CoyoteAdapter.java:233)
    at com.sun.enterprise.v3.services.impl.ContainerMapper.service(ContainerMapper.java:165)
    at com.sun.grizzly.http.ProcessorTask.invokeAdapter(ProcessorTask.java:791)
    at com.sun.grizzly.http.ProcessorTask.doProcess(ProcessorTask.java:693)
    at com.sun.grizzly.http.ProcessorTask.process(ProcessorTask.java:954)
    at com.sun.grizzly.http.DefaultProtocolFilter.execute(DefaultProtocolFilter.java:170)
    at com.sun.grizzly.DefaultProtocolChain.executeProtocolFilter(DefaultProtocolChain.java:135)
    at com.sun.grizzly.DefaultProtocolChain.execute(DefaultProtocolChain.java:102)
    at com.sun.grizzly.DefaultProtocolChain.execute(DefaultProtocolChain.java:88)
    at com.sun.grizzly.http.HttpProtocolChain.execute(HttpProtocolChain.java:76)
    at com.sun.grizzly.ProtocolChainContextTask.doCall(ProtocolChainContextTask.java:53)
    at com.sun.grizzly.SelectionKeyContextTask.call(SelectionKeyContextTask.java:57)
    at com.sun.grizzly.ContextTask.run(ContextTask.java:69)
    at com.sun.grizzly.util.AbstractThreadPool$Worker.doWork(AbstractThreadPool.java:330)
    at com.sun.grizzly.util.AbstractThreadPool$Worker.run(AbstractThreadPool.java:309)
    at java.lang.Thread.run(Thread.java:619)
- Component Tree

- Scoped Variables
Request ParametersName  Value
None

View AttributesName Value
None

Request AttributesName  Value
None

Flash AttributesName    Value
None

Session AttributesName  Value
None

Application AttributesName  Value
csfcff  com.sun.faces.context.flash.ELFlash@119f705d

拜托，你会这么好心，帮我解决这个问题吗？

感谢您的任何建议。

  <locale-config>
        <default-locale>en</default-locale>
        <supported-locale>en</supported-locale>
        <supported-locale>sk</supported-locale>
        <supported-locale>ko</supported-locale>
    </locale-config>
4

2 回答 2

1

好吧，您需要设置默认值。任何一个

Locale currentLocale = FacesContext.getCurrentContext()
           .getApplication().getDefaultLocale();

或者

@PostConstruct
public void init() {
    currentLocale = FacesContext.getCurrentContext()
           .getApplication().getDefaultLocale();
}
于 2010-03-02T23:38:24.763 回答
0

该错误说它Locale是空的，而它可能不是空的。您需要使用ExternalContext#getRequestLocale()which 将返回客户端语言环境进行预初始化，而不是使用Application#getDefaultLocale()which 将返回服务器端语言环境，null如果未明确配置，则可能是。

所以，更新你的代码

public changeLang() {
    this.currentLocale = FacesContext.getCurrentInstance().getExternalContext().getRequestLocale();
}

也就是说，建议遵守Sun Java Naming Conventions。类名应该以大写开头，否则会因为它看起来像方法而混淆大家。重命名changeLang为ChangeLang.

于 2010-03-02T23:43:39.493 回答