JSF 2.0 自定义异常处理程序 - ViewHandler 未在 Weld 应用程序中重定向

Question

我使用 Ed Burns 建议的自定义异常handler 每当发生特定异常时显示错误页面。我还尝试在上下文不活动时显示错误页面。 然而，这部分（第 45./46 行）会引起麻烦：

nav.handleNavigation(fc, null, "viewExpired");
fc.renderResponse();

这里出现了完整的 CustomExceptionHandler （按照 Ed Burns 在他的博客中建议的那样正确配置）

package com.sun.faces;
import java.util.Iterator;
import java.util.Map;
import javax.enterprise.context.ContextNotActiveException;
import javax.faces.FacesException;
import javax.faces.application.NavigationHandler;
import javax.faces.application.ViewExpiredException;
import javax.faces.component.UIViewRoot;
import javax.faces.context.ExceptionHandler;
import javax.faces.context.ExceptionHandlerWrapper;
import javax.faces.context.FacesContext;
import javax.faces.event.ExceptionQueuedEvent;
import javax.faces.event.ExceptionQueuedEventContext;

public class ViewExpiredExceptionExceptionHandler extends ExceptionHandlerWrapper {

private ExceptionHandler wrapped;

public ViewExpiredExceptionExceptionHandler(ExceptionHandler wrapped) {
    this.wrapped = wrapped;
}

@Override
public ExceptionHandler getWrapped() {
    return this.wrapped;
}

@Override
public void handle() throws FacesException {
    for (Iterator<ExceptionQueuedEvent> i = getUnhandledExceptionQueuedEvents().iterator(); i.hasNext();) {
        ExceptionQueuedEvent event = i.next();
        ExceptionQueuedEventContext context = (ExceptionQueuedEventContext) event.getSource();
        Throwable t = context.getException();
        if (t instanceof ViewExpiredException) {
            ViewExpiredException vee = (ViewExpiredException) t;
            FacesContext fc = FacesContext.getCurrentInstance();
            Map<String, Object> requestMap = fc.getExternalContext().getRequestMap();
            NavigationHandler nav =
                    fc.getApplication().getNavigationHandler();
            try {
                // Push some useful stuff to the request scope for
                // use in the page
                requestMap.put("currentViewId", vee.getViewId());

                nav.handleNavigation(fc, null, "viewExpired");
                fc.renderResponse();

            } finally {
                i.remove();
            }
        }
    if (t instanceof ContextNotActiveException) {
    FacesContext fc = FacesContext.getCurrentInstance();
            NavigationHandler nav =
                    fc.getApplication().getNavigationHandler();

         try {
                nav.handleNavigation(fc, null, "contextNotActive");
                fc.renderResponse();

         } finally {
         i.remove();
     }
     }
    }
    // At this point, the queue will not contain any exceptions I want to handle (for now).
    // Therefore, let the parent handle them.
    getWrapped().handle();

    }
}

但是我总是在控制台中得到“视图无法渲染”的打印输出。那么为什么它不呈现该错误页面。我认为这是由不活动的上下文（由 NavigationHandler 使用）引起的！

任何人都可以确认此行为吗？

PS：我正在使用 Weld 1.1 和 Mojarra 2.0.4

Answer 1

我认为您必须在 faces-config.xml 文件中添加导航规则，如下所示：

 <navigation-rule>
  <from-view-id>*</from-view-id>
  <navigation-case>
   <from-outcome>contextNotActive</from-outcome>
   <to-view-id>/contextNotActive.xhtml</to-view-id>
  </navigation-case>
 </navigation-rule>