PropertyNotFoundException后的JSF错误页

Question

我有通常的JSF错误处理设置

<error-page>
    <exception-type>java.lang.Throwable</exception-type>
    <location>/error.xhtml</location>
</error-page>

这在OmniFaces的FullAjaxExceptionHandler中运行得很好。

现在，当facelet呈现过程中出现错误(即错误的属性引用-类型)时，将抛出javax.el.PropertyNotFoundException，并显示错误页，但引发下面的异常。

Mar 17, 2015 10:22:09 AM com.sun.faces.application.view.FaceletViewHandlingStrategy handleRenderException
SEVERE: Error Rendering View[/error.xhtml]
java.lang.IllegalStateException: getOutputStream() has already been called for this response
at org.apache.catalina.connector.Response.getWriter(Response.java:578)
at org.apache.catalina.connector.ResponseFacade.getWriter(ResponseFacade.java:212)
at javax.servlet.ServletResponseWrapper.getWriter(ServletResponseWrapper.java:109)
at com.sun.faces.context.ExternalContextImpl.getResponseOutputWriter(ExternalContextImpl.java:723)
at com.sun.faces.application.view.FaceletViewHandlingStrategy.createResponseWriter(FaceletViewHandlingStrategy.java:938)
at com.sun.faces.application.view.FaceletViewHandlingStrategy.renderView(FaceletViewHandlingStrategy.java:377)
at com.sun.faces.application.view.MultiViewHandler.renderView(MultiViewHandler.java:125)
at javax.faces.application.ViewHandlerWrapper.renderView(ViewHandlerWrapper.java:288)
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:594)
at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:291)
at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:206)
at org.apache.catalina.core.ApplicationDispatcher.invoke(ApplicationDispatcher.java:721)
at org.apache.catalina.core.ApplicationDispatcher.doInclude(ApplicationDispatcher.java:584)
at org.apache.catalina.core.ApplicationDispatcher.include(ApplicationDispatcher.java:523)
at org.apache.catalina.core.StandardHostValve.custom(StandardHostValve.java:427)
at org.apache.catalina.core.StandardHostValve.throwable(StandardHostValve.java:376)
at org.apache.catalina.core.StandardHostValve.invoke(StandardHostValve.java:174)
at org.apache.catalina.valves.ErrorReportValve.invoke(ErrorReportValve.java:79)
at org.apache.catalina.valves.AbstractAccessLogValve.invoke(AbstractAccessLogValve.java:610)
at org.apache.catalina.core.StandardEngineValve.invoke(StandardEngineValve.java:88)
at org.apache.catalina.connector.CoyoteAdapter.service(CoyoteAdapter.java:537)
at org.apache.coyote.http11.AbstractHttp11Processor.process(AbstractHttp11Processor.java:1085)
at org.apache.coyote.AbstractProtocol$AbstractConnectionHandler.process(AbstractProtocol.java:658)
at org.apache.coyote.http11.Http11Protocol$Http11ConnectionHandler.process(Http11Protocol.java:146)
at org.apache.tomcat.util.net.JIoEndpoint$SocketProcessor.run(JIoEndpoint.java:277)
at java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1145)
at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:615)
at org.apache.tomcat.util.threads.TaskThread$WrappingRunnable.run(TaskThread.java:61)
at java.lang.Thread.run(Thread.java:745)

据我所知，问题是原始页面的呈现已经开始，而getOutputStream()是called.Now，当错误页应该被呈现时，getOutputStream()将再次被调用，并且由于规范规定不能执行两次，所以会抛出上述异常。

或者我不明白什么？

当然，整个问题都是由facelet中的错误引起的，可以通过IDE进行验证，我只是想知道是否有一种方法可以显示这种类型或错误的错误页面。

谢谢

Answer 1

在回答我自己的问题时，出现此错误消息的原因是使用了素数面扩展布局。在这种情况下，当布局内容呈现失败时，布局本身就无法呈现。