Jsf2.0轉發頁面錯誤無參數

Question

你好，我有錯誤，當我轉發頁面沒有參數。這隻發生在構造函數中。沒有發生方法。

像

public EditNewsBean() throws Exception 
{ 
    log.info("In EditNewsBean Constructor"); 

    Object o1=request.getParameter("countryCode"); 
    Object o2=request.getParameter("editNewsID"); 
    if(o1==null || o2==null || o1.toString().length()==0 || o2.toString().length()==0) 
    { 
     FacesContext.getCurrentInstance().getExternalContext().redirect("/HeWebEV/admin/ManageNews.jsf"); 
    } 

    setEditNews(Facade.othfac().getTVecNewsFindAllValidTill(request.getParameter("countryCode").toString(),Integer.valueOf(request.getParameter("editNewsID")))); 
} 

和喜歡，當我路過申請表不帶參數我得到的錯誤，

com.sun.faces.mgbean.ManagedBeanCreationException: Cant instantiate class: com.efacec.sg.he.plugme.admin.EditNewsBean. 
     at com.sun.faces.mgbean.BeanBuilder.newBeanInstance(BeanBuilder.java:193) 
     at com.sun.faces.mgbean.BeanBuilder.build(BeanBuilder.java:102) 
     at com.sun.faces.mgbean.BeanManager.createAndPush(BeanManager.java:409) 
     at com.sun.faces.mgbean.BeanManager.create(BeanManager.java:269) 
     at com.sun.faces.el.ManagedBeanELResolver.resolveBean(ManagedBeanELResolver.java:244) 
     at com.sun.faces.el.ManagedBeanELResolver.getValue(ManagedBeanELResolver.java:116) 
     at com.sun.faces.el.DemuxCompositeELResolver._getValue(DemuxCompositeELResolver.java:176) 
     at com.sun.faces.el.DemuxCompositeELResolver.getValue(DemuxCompositeELResolver.java:203) 
     at org.apache.el.parser.AstIdentifier.getValue(AstIdentifier.java:61) 
     at org.apache.el.parser.AstValue.getValue(AstValue.java:107) 
     at org.apache.el.ValueExpressionImpl.getValue(ValueExpressionImpl.java:186) 
     at com.sun.faces.facelets.el.TagValueExpression.getValue(TagValueExpression.java:109) 
     at javax.faces.component.ComponentStateHelper.eval(ComponentStateHelper.java:194) 
     at javax.faces.component.ComponentStateHelper.eval(ComponentStateHelper.java:182) 
     at javax.faces.component.UIOutput.getValue(UIOutput.java:169) 
     at com.sun.faces.renderkit.html_basic.HtmlBasicInputRenderer.getValue(HtmlBasicInputRenderer.java:205) 
     at com.sun.faces.renderkit.html_basic.HtmlBasicRenderer.getCurrentValue(HtmlBasicRenderer.java:355) 
     at com.sun.faces.renderkit.html_basic.HtmlBasicRenderer.encodeEnd(HtmlBasicRenderer.java:164) 
     at javax.faces.component.UIComponentBase.encodeEnd(UIComponentBase.java:875) 
     at com.sun.faces.renderkit.html_basic.HtmlBasicRenderer.encodeRecursive(HtmlBasicRenderer.java:312) 
     at com.sun.faces.renderkit.html_basic.GridRenderer.renderRow(GridRenderer.java:185) 
     at com.sun.faces.renderkit.html_basic.GridRenderer.encodeChildren(GridRenderer.java:129) 
     at javax.faces.component.UIComponentBase.encodeChildren(UIComponentBase.java:845) 
     at org.primefaces.renderkit.CoreRenderer.renderChild(CoreRenderer.java:59) 
     at org.primefaces.renderkit.CoreRenderer.renderChildren(CoreRenderer.java:47) 
     at org.primefaces.component.panel.PanelRenderer.encodeContent(PanelRenderer.java:185) 
     at org.primefaces.component.panel.PanelRenderer.encodeMarkup(PanelRenderer.java:108) 
     at org.primefaces.component.panel.PanelRenderer.encodeEnd(PanelRenderer.java:55) 
     at javax.faces.component.UIComponentBase.encodeEnd(UIComponentBase.java:875) 
     at javax.faces.component.UIComponent.encodeAll(UIComponent.java:1763) 
     at javax.faces.render.Renderer.encodeChildren(Renderer.java:168) 
     at javax.faces.component.UIComponentBase.encodeChildren(UIComponentBase.java:845) 
     at javax.faces.component.UIComponent.encodeAll(UIComponent.java:1756) 
     at javax.faces.component.UIComponent.encodeAll(UIComponent.java:1759) 
     at javax.faces.component.UIComponent.encodeAll(UIComponent.java:1759) 
     at com.sun.faces.application.view.FaceletViewHandlingStrategy.renderView(FaceletViewHandlingStrategy.java:401) 
     at com.sun.faces.application.view.MultiViewHandler.renderView(MultiViewHandler.java:131) 
     at com.sun.faces.lifecycle.RenderResponsePhase.execute(RenderResponsePhase.java:121) 
     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:410) 
     at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:290) 
     at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:206) 
     at org.primefaces.webapp.filter.FileUploadFilter.doFilter(FileUploadFilter.java:79) 
     at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:235) 
     at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:206) 
     at org.jboss.web.tomcat.filters.ReplyHeaderFilter.doFilter(ReplyHeaderFilter.java:96) 
     at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:235) 
     at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:206) 
     at org.apache.catalina.core.StandardWrapperValve.invoke(StandardWrapperValve.java:235) 
     at org.apache.catalina.core.StandardContextValve.invoke(StandardContextValve.java:191) 
     at org.jboss.web.tomcat.security.SecurityAssociationValve.invoke(SecurityAssociationValve.java:190) 
     at org.jboss.web.tomcat.security.JaccContextValve.invoke(JaccContextValve.java:92) 
     at org.jboss.web.tomcat.security.SecurityContextEstablishmentValve.process(SecurityContextEstablishmentValve.java:126) 
     at org.jboss.web.tomcat.security.SecurityContextEstablishmentValve.invoke(SecurityContextEstablishmentValve.java:70) 
     at org.apache.catalina.core.StandardHostValve.invoke(StandardHostValve.java:127) 
     at org.apache.catalina.valves.ErrorReportValve.invoke(ErrorReportValve.java:102) 
     at org.jboss.web.tomcat.service.jca.CachedConnectionValve.invoke(CachedConnectionValve.java:158) 
     at org.apache.catalina.core.StandardEngineValve.invoke(StandardEngineValve.java:109) 
     at org.apache.catalina.connector.CoyoteAdapter.service(CoyoteAdapter.java:330) 
     at org.apache.coyote.http11.Http11Processor.process(Http11Processor.java:829) 
     at org.apache.coyote.http11.Http11Protocol$Http11ConnectionHandler.process(Http11Protocol.java:598) 
     at org.apache.tomcat.util.net.JIoEndpoint$Worker.run(JIoEndpoint.java:447) 
     at java.lang.Thread.run(Thread.java:619) 
Caused by: java.lang.IllegalStateException 
     at org.apache.catalina.connector.ResponseFacade.sendRedirect(ResponseFacade.java:435) 
     at com.sun.faces.context.ExternalContextImpl.redirect(ExternalContextImpl.java:576) 
     at com.efacec.sg.he.plugme.admin.EditNewsBean.<init>(EditNewsBean.java:33) 
     at sun.reflect.NativeConstructorAccessorImpl.newInstance0(Native Method) 
     at sun.reflect.NativeConstructorAccessorImpl.newInstance(NativeConstructorAccessorImpl.java:39) 
     at sun.reflect.DelegatingConstructorAccessorImpl.newInstance(DelegatingConstructorAccessorImpl.java:27) 
     at java.lang.reflect.Constructor.newInstance(Constructor.java:513) 
     at java.lang.Class.newInstance0(Class.java:355) 
     at java.lang.Class.newInstance(Class.java:308) 
     at com.sun.faces.mgbean.BeanBuilder.newBeanInstance(BeanBuilder.java:188) 
     ... 63 more 
15:07:00,342 INFO [context] Exception when handling error trying to reset the response. 
com.sun.faces.mgbean.ManagedBeanCreationException: Cant instantiate class: com.efacec.sg.he.plugme.admin.EditNewsBean. 
     at com.sun.faces.mgbean.BeanBuilder.newBeanInstance(BeanBuilder.java:193) 
     at com.sun.faces.mgbean.BeanBuilder.build(BeanBuilder.java:102) 
     at com.sun.faces.mgbean.BeanManager.createAndPush(BeanManager.java:409) 
     at com.sun.faces.mgbean.BeanManager.create(BeanManager.java:269) 
     at com.sun.faces.el.ManagedBeanELResolver.resolveBean(ManagedBeanELResolver.java:244) 
     at com.sun.faces.el.ManagedBeanELResolver.getValue(ManagedBeanELResolver.java:116) 
     at com.sun.faces.el.DemuxCompositeELResolver._getValue(DemuxCompositeELResolver.java:176) 
     at com.sun.faces.el.DemuxCompositeELResolver.getValue(DemuxCompositeELResolver.java:203) 
     at org.apache.el.parser.AstIdentifier.getValue(AstIdentifier.java:61) 
     at org.apache.el.parser.AstValue.getValue(AstValue.java:107) 
     at org.apache.el.ValueExpressionImpl.getValue(ValueExpressionImpl.java:186) 
     at com.sun.faces.facelets.el.TagValueExpression.getValue(TagValueExpression.java:109) 
     at javax.faces.component.ComponentStateHelper.eval(ComponentStateHelper.java:194) 
     at javax.faces.component.ComponentStateHelper.eval(ComponentStateHelper.java:182) 
     at javax.faces.component.UIOutput.getValue(UIOutput.java:169) 
     at com.sun.faces.renderkit.html_basic.HtmlBasicInputRenderer.getValue(HtmlBasicInputRenderer.java:205) 
     at com.sun.faces.renderkit.html_basic.HtmlBasicRenderer.getCurrentValue(HtmlBasicRenderer.java:355) 
     at com.sun.faces.renderkit.html_basic.HtmlBasicRenderer.encodeEnd(HtmlBasicRenderer.java:164) 
     at javax.faces.component.UIComponentBase.encodeEnd(UIComponentBase.java:875) 
     at com.sun.faces.renderkit.html_basic.HtmlBasicRenderer.encodeRecursive(HtmlBasicRenderer.java:312) 
     at com.sun.faces.renderkit.html_basic.GridRenderer.renderRow(GridRenderer.java:185) 
     at com.sun.faces.renderkit.html_basic.GridRenderer.encodeChildren(GridRenderer.java:129) 
     at javax.faces.component.UIComponentBase.encodeChildren(UIComponentBase.java:845) 
     at org.primefaces.renderkit.CoreRenderer.renderChild(CoreRenderer.java:59) 
     at org.primefaces.renderkit.CoreRenderer.renderChildren(CoreRenderer.java:47) 
     at org.primefaces.component.panel.PanelRenderer.encodeContent(PanelRenderer.java:185) 
     at org.primefaces.component.panel.PanelRenderer.encodeMarkup(PanelRenderer.java:108) 
     at org.primefaces.component.panel.PanelRenderer.encodeEnd(PanelRenderer.java:55) 
     at javax.faces.component.UIComponentBase.encodeEnd(UIComponentBase.java:875) 
     at javax.faces.component.UIComponent.encodeAll(UIComponent.java:1763) 
     at javax.faces.render.Renderer.encodeChildren(Renderer.java:168) 
     at javax.faces.component.UIComponentBase.encodeChildren(UIComponentBase.java:845) 
     at javax.faces.component.UIComponent.encodeAll(UIComponent.java:1756) 
     at javax.faces.component.UIComponent.encodeAll(UIComponent.java:1759) 
     at javax.faces.component.UIComponent.encodeAll(UIComponent.java:1759) 
     at com.sun.faces.application.view.FaceletViewHandlingStrategy.renderView(FaceletViewHandlingStrategy.java:401) 
     at com.sun.faces.application.view.MultiViewHandler.renderView(MultiViewHandler.java:131) 
     at com.sun.faces.lifecycle.RenderResponsePhase.execute(RenderResponsePhase.java:121) 
     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:410) 
     at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:290) 
     at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:206) 
     at org.primefaces.webapp.filter.FileUploadFilter.doFilter(FileUploadFilter.java:79) 
     at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:235) 
     at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:206) 
     at org.jboss.web.tomcat.filters.ReplyHeaderFilter.doFilter(ReplyHeaderFilter.java:96) 
     at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:235) 
     at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:206) 
     at org.apache.catalina.core.StandardWrapperValve.invoke(StandardWrapperValve.java:235) 
     at org.apache.catalina.core.StandardContextValve.invoke(StandardContextValve.java:191) 
     at org.jboss.web.tomcat.security.SecurityAssociationValve.invoke(SecurityAssociationValve.java:190) 
     at org.jboss.web.tomcat.security.JaccContextValve.invoke(JaccContextValve.java:92) 
     at org.jboss.web.tomcat.security.SecurityContextEstablishmentValve.process(SecurityContextEstablishmentValve.java:126) 
     at org.jboss.web.tomcat.security.SecurityContextEstablishmentValve.invoke(SecurityContextEstablishmentValve.java:70) 
     at org.apache.catalina.core.StandardHostValve.invoke(StandardHostValve.java:127) 
     at org.apache.catalina.valves.ErrorReportValve.invoke(ErrorReportValve.java:102) 
     at org.jboss.web.tomcat.service.jca.CachedConnectionValve.invoke(CachedConnectionValve.java:158) 
     at org.apache.catalina.core.StandardEngineValve.invoke(StandardEngineValve.java:109) 
     at org.apache.catalina.connector.CoyoteAdapter.service(CoyoteAdapter.java:330) 
     at org.apache.coyote.http11.Http11Processor.process(Http11Processor.java:829) 
     at org.apache.coyote.http11.Http11Protocol$Http11ConnectionHandler.process(Http11Protocol.java:598) 
     at org.apache.tomcat.util.net.JIoEndpoint$Worker.run(JIoEndpoint.java:447) 
     at java.lang.Thread.run(Thread.java:619) 
Caused by: java.lang.IllegalStateException 
     at org.apache.catalina.connector.ResponseFacade.sendRedirect(ResponseFacade.java:435) 
     at com.sun.faces.context.ExternalContextImpl.redirect(ExternalContextImpl.java:576) 
     at com.efacec.sg.he.plugme.admin.EditNewsBean.<init>(EditNewsBean.java:33) 
     at sun.reflect.NativeConstructorAccessorImpl.newInstance0(Native Method) 
     at sun.reflect.NativeConstructorAccessorImpl.newInstance(NativeConstructorAccessorImpl.java:39) 
     at sun.reflect.DelegatingConstructorAccessorImpl.newInstance(DelegatingConstructorAccessorImpl.java:27) 
     at java.lang.reflect.Constructor.newInstance(Constructor.java:513) 
     at java.lang.Class.newInstance0(Class.java:355) 
     at java.lang.Class.newInstance(Class.java:308) 
     at com.sun.faces.mgbean.BeanBuilder.newBeanInstance(BeanBuilder.java:188) 
     ... 63 more 
15:07:00,366 ERROR [[Faces Servlet]] Servlet.service() for servlet Faces Servlet threw exception 
java.lang.IllegalStateException 
     at org.apache.catalina.connector.ResponseFacade.sendRedirect(ResponseFacade.java:435) 
     at com.sun.faces.context.ExternalContextImpl.redirect(ExternalContextImpl.java:576) 
     at com.efacec.sg.he.plugme.admin.EditNewsBean.<init>(EditNewsBean.java:33) 
     at sun.reflect.NativeConstructorAccessorImpl.newInstance0(Native Method) 
     at sun.reflect.NativeConstructorAccessorImpl.newInstance(NativeConstructorAccessorImpl.java:39) 
     at sun.reflect.DelegatingConstructorAccessorImpl.newInstance(DelegatingConstructorAccessorImpl.java:27) 
     at java.lang.reflect.Constructor.newInstance(Constructor.java:513) 
     at java.lang.Class.newInstance0(Class.java:355) 
     at java.lang.Class.newInstance(Class.java:308) 
     at com.sun.faces.mgbean.BeanBuilder.newBeanInstance(BeanBuilder.java:188) 
     at com.sun.faces.mgbean.BeanBuilder.build(BeanBuilder.java:102) 
     at com.sun.faces.mgbean.BeanManager.createAndPush(BeanManager.java:409) 
     at com.sun.faces.mgbean.BeanManager.create(BeanManager.java:269) 
     at com.sun.faces.el.ManagedBeanELResolver.resolveBean(ManagedBeanELResolver.java:244) 
     at com.sun.faces.el.ManagedBeanELResolver.getValue(ManagedBeanELResolver.java:116) 
     at com.sun.faces.el.DemuxCompositeELResolver._getValue(DemuxCompositeELResolver.java:176) 
     at com.sun.faces.el.DemuxCompositeELResolver.getValue(DemuxCompositeELResolver.java:203) 
     at org.apache.el.parser.AstIdentifier.getValue(AstIdentifier.java:61) 
     at org.apache.el.parser.AstValue.getValue(AstValue.java:107) 
     at org.apache.el.ValueExpressionImpl.getValue(ValueExpressionImpl.java:186) 
     at com.sun.faces.facelets.el.TagValueExpression.getValue(TagValueExpression.java:109) 
     at javax.faces.component.ComponentStateHelper.eval(ComponentStateHelper.java:194) 
     at javax.faces.component.ComponentStateHelper.eval(ComponentStateHelper.java:182) 
     at javax.faces.component.UIOutput.getValue(UIOutput.java:169) 
     at com.sun.faces.renderkit.html_basic.HtmlBasicInputRenderer.getValue(HtmlBasicInputRenderer.java:205) 
     at com.sun.faces.renderkit.html_basic.HtmlBasicRenderer.getCurrentValue(HtmlBasicRenderer.java:355) 
     at com.sun.faces.renderkit.html_basic.HtmlBasicRenderer.encodeEnd(HtmlBasicRenderer.java:164) 
     at javax.faces.component.UIComponentBase.encodeEnd(UIComponentBase.java:875) 
     at com.sun.faces.renderkit.html_basic.HtmlBasicRenderer.encodeRecursive(HtmlBasicRenderer.java:312) 
     at com.sun.faces.renderkit.html_basic.GridRenderer.renderRow(GridRenderer.java:185) 
     at com.sun.faces.renderkit.html_basic.GridRenderer.encodeChildren(GridRenderer.java:129) 
     at javax.faces.component.UIComponentBase.encodeChildren(UIComponentBase.java:845) 
     at org.primefaces.renderkit.CoreRenderer.renderChild(CoreRenderer.java:59) 
     at org.primefaces.renderkit.CoreRenderer.renderChildren(CoreRenderer.java:47) 
     at org.primefaces.component.panel.PanelRenderer.encodeContent(PanelRenderer.java:185) 
     at org.primefaces.component.panel.PanelRenderer.encodeMarkup(PanelRenderer.java:108) 
     at org.primefaces.component.panel.PanelRenderer.encodeEnd(PanelRenderer.java:55) 
     at javax.faces.component.UIComponentBase.encodeEnd(UIComponentBase.java:875) 
     at javax.faces.component.UIComponent.encodeAll(UIComponent.java:1763) 
     at javax.faces.render.Renderer.encodeChildren(Renderer.java:168) 
     at javax.faces.component.UIComponentBase.encodeChildren(UIComponentBase.java:845) 
     at javax.faces.component.UIComponent.encodeAll(UIComponent.java:1756) 
     at javax.faces.component.UIComponent.encodeAll(UIComponent.java:1759) 
     at javax.faces.component.UIComponent.encodeAll(UIComponent.java:1759) 
     at com.sun.faces.application.view.FaceletViewHandlingStrategy.renderView(FaceletViewHandlingStrategy.java:401) 
     at com.sun.faces.application.view.MultiViewHandler.renderView(MultiViewHandler.java:131) 
     at com.sun.faces.lifecycle.RenderResponsePhase.execute(RenderResponsePhase.java:121) 
     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:410) 
     at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:290) 
     at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:206) 
     at org.primefaces.webapp.filter.FileUploadFilter.doFilter(FileUploadFilter.java:79) 
     at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:235) 
     at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:206) 
     at org.jboss.web.tomcat.filters.ReplyHeaderFilter.doFilter(ReplyHeaderFilter.java:96) 
     at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:235) 
     at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:206) 
     at org.apache.catalina.core.StandardWrapperValve.invoke(StandardWrapperValve.java:235) 
     at org.apache.catalina.core.StandardContextValve.invoke(StandardContextValve.java:191) 
     at org.jboss.web.tomcat.security.SecurityAssociationValve.invoke(SecurityAssociationValve.java:190) 
     at org.jboss.web.tomcat.security.JaccContextValve.invoke(JaccContextValve.java:92) 
     at org.jboss.web.tomcat.security.SecurityContextEstablishmentValve.process(SecurityContextEstablishmentValve.java:126) 
     at org.jboss.web.tomcat.security.SecurityContextEstablishmentValve.invoke(SecurityContextEstablishmentValve.java:70) 
     at org.apache.catalina.core.StandardHostValve.invoke(StandardHostValve.java:127) 
     at org.apache.catalina.valves.ErrorReportValve.invoke(ErrorReportValve.java:102) 
     at org.jboss.web.tomcat.service.jca.CachedConnectionValve.invoke(CachedConnectionValve.java:158) 
     at org.apache.catalina.core.StandardEngineValve.invoke(StandardEngineValve.java:109) 
     at org.apache.catalina.connector.CoyoteAdapter.service(CoyoteAdapter.java:330) 
     at org.apache.coyote.http11.Http11Processor.process(Http11Processor.java:829) 
     at org.apache.coyote.http11.Http11Protocol$Http11ConnectionHandler.process(Http11Protocol.java:598) 
     at org.apache.tomcat.util.net.JIoEndpoint$Worker.run(JIoEndpoint.java:447) 
     at java.lang.Thread.run(Thread.java:619) 
15:07:00,405 ERROR [[localhost]] Exception Processing ErrorPage[exceptionType=java.lang.Exception, location=/error.xhtml] 
java.lang.IllegalStateException: Cannot reset buffer after response has been committed 
     at org.apache.catalina.connector.Response.resetBuffer(Response.java:684) 
     at org.apache.catalina.connector.Response.resetBuffer(Response.java:705) 
     at org.apache.catalina.core.StandardHostValve.custom(StandardHostValve.java:409) 
     at org.apache.catalina.core.StandardHostValve.throwable(StandardHostValve.java:270) 
     at org.apache.catalina.core.StandardHostValve.invoke(StandardHostValve.java:141) 
     at org.apache.catalina.valves.ErrorReportValve.invoke(ErrorReportValve.java:102) 
     at org.jboss.web.tomcat.service.jca.CachedConnectionValve.invoke(CachedConnectionValve.java:158) 
     at org.apache.catalina.core.StandardEngineValve.invoke(StandardEngineValve.java:109) 
     at org.apache.catalina.connector.CoyoteAdapter.service(CoyoteAdapter.java:330) 
     at org.apache.coyote.http11.Http11Processor.process(Http11Processor.java:829) 
     at org.apache.coyote.http11.Http11Protocol$Http11ConnectionHandler.process(Http11Protocol.java:598) 
     at org.apache.tomcat.util.net.JIoEndpoint$Worker.run(JIoEndpoint.java:447) 
     at java.lang.Thread.run(Thread.java:619) 

Answer 1

com.sun.faces.mgbean.ManagedBeanCreationException: Cant instantiate class: com.efacec.sg.he.plugme.admin.EditNewsBean. 
... 
java.lang.IllegalStateException: Cannot reset buffer after response has been committed 

這個bean顯然是相當引用「晚「在視圖中。在渲染響應階段，視圖的一部分已經發送（提交）到響應。將響應改爲重定向太遲了。服務器無法從客戶端取回已發送的字節。服務器將拋出一個IllegalStateException，客戶端將以半響的響應結束。

您需要在之前執行重定向任何字節在響應中已發送到客戶端。您可以使用<f:event type="preRenderView">偵聽器來實現此目的。增加這個地方的視圖（最自我記錄將是把這個模板中的客戶端的頂部）：

<f:event type="preRenderView" listener="#{editNewsBean.init}" /> 

而構造函數的代碼轉移到該方法。

public void init() { 
    // ... 
} 

---

無關到具體的問題，不要忘記添加一個else {}塊setEditNews()。當條件符合重定向條件時，您不希望它被調用，對嗎？否則你可能會面臨NullPointerException。此外，getParameter()上的toString()是完全不必要的。此外，您應該收集請求參數<f:viewParam> or @ManagedProperty或至少ExternalContext#getRequestParameterMap()。您似乎已將HttpServletRequest分配爲該bean的實例變量，這是一個非常糟糕的主意。最後，你在這裏執行重定向，而不是前鋒。