项目启动一段时间后，进入初始页面，会出现java.util.EmptyStackException异常，刷新一次后异常就消失了。

An exception has occurred.  


You may continue by restarting the session.

 

[ +/- ] Exception: There was an error borrowing the page with key PageKey[_pageName='Home' , _locale=zh_CN ] from the page pool. org.apache.hivemind.ApplicationRuntimeException 
There was an error borrowing the page with key PageKey[_pageName='Home' , _locale=zh_CN ] from the page pool. 
   
[ +/- ] Exception: java.util.EmptyStackException 
 
Stack Trace: 
java.util.Stack.peek(Unknown Source) 
java.util.Stack.pop(Unknown Source) 
org.apache.tapestry.pageload.PageLoader.endConstructComponent(PageLoader.java:469) 
org.apache.tapestry.pageload.PageLoader.constructComponent(PageLoader.java:424) 
org.apache.tapestry.pageload.PageLoader.loadPage(PageLoader.java:639) 
$IPageLoader_118e361a96c.loadPage($IPageLoader_118e361a96c.java) 
$IPageLoader_118e361a96d.loadPage($IPageLoader_118e361a96d.java) 
org.apache.tapestry.pageload.PageSource.makeObject(PageSource.java:153) 
org.apache.commons.pool.impl.GenericKeyedObjectPool.borrowObject(GenericKeyedObjectPool.java:797) 
org.apache.tapestry.pageload.PageSource.getPage(PageSource.java:177) 
$IPageSource_118e361a8bf.getPage($IPageSource_118e361a8bf.java) 
org.apache.tapestry.engine.RequestCycle.loadPage(RequestCycle.java:239) 
org.apache.tapestry.engine.RequestCycle.getPage(RequestCycle.java:226) 
org.apache.tapestry.engine.RequestCycle.activate(RequestCycle.java:559) 
org.apache.tapestry.engine.HomeService.service(HomeService.java:66) 
$IEngineService_118e361a954.service($IEngineService_118e361a954.java) 
org.apache.tapestry.services.impl.EngineServiceOuterProxy.service(EngineServiceOuterProxy.java:72) 
org.apache.tapestry.engine.AbstractEngine.service(AbstractEngine.java:237) 
org.apache.tapestry.services.impl.InvokeEngineTerminator.service(InvokeEngineTerminator.java:54) 
$WebRequestServicer_118e361a92d.service($WebRequestServicer_118e361a92d.java) 
$WebRequestServicer_118e361a929.service($WebRequestServicer_118e361a929.java) 
org.apache.tapestry.services.impl.WebRequestServicerPipelineBridge.service(WebRequestServicerPipelineBridge.java:61) 
$ServletRequestServicer_118e361a90f.service($ServletRequestServicer_118e361a90f.java) 
org.apache.tapestry.request.DecodedRequestInjector.service(DecodedRequestInjector.java:55) 
$ServletRequestServicerFilter_118e361a90b.service($ServletRequestServicerFilter_118e361a90b.java) 
$ServletRequestServicer_118e361a911.service($ServletRequestServicer_118e361a911.java) 
org.apache.tapestry.multipart.MultipartDecoderFilter.service(MultipartDecoderFilter.java:52) 
$ServletRequestServicerFilter_118e361a909.service($ServletRequestServicerFilter_118e361a909.java) 
$ServletRequestServicer_118e361a911.service($ServletRequestServicer_118e361a911.java) 
org.apache.tapestry.services.impl.SetupRequestEncoding.service(SetupRequestEncoding.java:53) 
$ServletRequestServicerFilter_118e361a90d.service($ServletRequestServicerFilter_118e361a90d.java) 
$ServletRequestServicer_118e361a911.service($ServletRequestServicer_118e361a911.java) 
$ServletRequestServicer_118e361a903.service($ServletRequestServicer_118e361a903.java) 
org.apache.tapestry.ApplicationServlet.doService(ApplicationServlet.java:126) 
org.apache.tapestry.ApplicationServlet.doGet(ApplicationServlet.java:103) 
javax.servlet.http.HttpServlet.service(HttpServlet.java:689) 
javax.servlet.http.HttpServlet.service(HttpServlet.java:802) 
org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:252) 
org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:173) 
com.myso.util.SetCharacterEncodingFilter.doFilter(SetCharacterEncodingFilter.java:34) 
org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:202) 
org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:173) 
org.apache.catalina.core.StandardWrapperValve.invoke(StandardWrapperValve.java:213) 
org.apache.catalina.core.StandardContextValve.invoke(StandardContextValve.java:178) 
org.apache.catalina.core.StandardHostValve.invoke(StandardHostValve.java:126) 
org.apache.catalina.valves.ErrorReportValve.invoke(ErrorReportValve.java:105) 
org.apache.catalina.core.StandardEngineValve.invoke(StandardEngineValve.java:107) 
org.apache.catalina.connector.CoyoteAdapter.service(CoyoteAdapter.java:148) 
org.apache.coyote.http11.Http11Processor.process(Http11Processor.java:869) 
org.apache.coyote.http11.Http11BaseProtocol$Http11ConnectionHandler.processConnection(Http11BaseProtocol.java:664) 
org.apache.tomcat.util.net.PoolTcpEndpoint.processSocket(PoolTcpEndpoint.java:527) 
org.apache.tomcat.util.net.LeaderFollowerWorkerThread.runIt(LeaderFollowerWorkerThread.java:80) 
org.apache.tomcat.util.threads.ThreadPool$ControlRunnable.run(ThreadPool.java:684) 
java.lang.Thread.run(Unknown Source) 
 

请问，异常发生的原因可能是什么？什么导致了空栈的错误？

 

石沉大海...

tapestry的版本多少，看是不是这个bug
https://issues.apache.org/jira/browse/TAPESTRY-638

谢谢tapestry大哥，版本是4.1.2（现已升为4.1.5），不是你说的那个bug。