那些遇到过的问题

没有参数的Jsf2.0转发页面错误

KSH*_*TiJ 5 jsf-2

你好我没有参数转发页面时有错误.这只发生在构造函数中.方法没有发生.

喜欢

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"))));
}
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当我通过没有参数的请求表格时,我得到的错误就像,

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)
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Bal*_*usC 4 

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
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显然，该 Bean 在视图中被引用得相当“晚”。在渲染响应阶段，视图的一部分已被发送（提交）到响应。那时将响应更改为重定向为时已晚。服务器无法从客户端取回已发送的字节。服务器会抛出一个IllegalStateException，而客户端最终将得到一个半生不熟的响应。

您需要在响应中将任何字节发送到客户端之前执行重定向。您可以通过<f:event type="preRenderView">侦听器来实现此目的。将其添加到视图中的某个位置（大多数自记录是将其放在模板客户端的顶部）：

<f:event type="preRenderView" listener="#{editNewsBean.init}" />
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并将构造函数的代码移至该方法中。

public void init() {
    // ...
}
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与具体问题无关，不要忘记添加一个else {}块 for setEditNews()。您不希望在条件符合重定向条件时调用它，对吧？否则你可能会面临NullPointerException。而且，那toString()是getParameter()完全没有必要的。此外，您应该通过<f:viewParam>或@ManagedProperty或至少收集请求参数ExternalContext#getRequestParameterMap()。您似乎已将其指定HttpServletRequest为 bean 的实例变量，这是一个非常糟糕的主意。最后，您在这里执行的是重定向，而不是转发。

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