Hi, I am using Struts 2.0.6, Tiles 2.0 and Tomcat 5.5.27. The application runs fine in the past, but recently we did some load testing and get the following exception intermittently during load test:
2010-04-08 05:51:09,970 ERROR [http-443-Processor22] ? - End event threw exception java.lang.NoSuchMethodException: No such accessible method: addAttribute() on object: org.apache.tiles.definition.digester.DigesterDefinitionsReader at org.apache.commons.beanutils.MethodUtils.invokeMethod(MethodUtils.java:250) at org.apache.commons.digester.SetNextRule.end(SetNextRule.java:208) at org.apache.commons.digester.Rule.end(Rule.java:228) at org.apache.commons.digester.Digester.endElement(Digester.java:1067) at org.apache.xerces.parsers.AbstractSAXParser.endElement(Unknown Source) at org.apache.xerces.parsers.AbstractXMLDocumentParser.emptyElement(Unknown Source) at org.apache.xerces.impl.dtd.XMLDTDValidator.emptyElement(Unknown Source) at org.apache.xerces.impl.XMLNSDocumentScannerImpl.scanStartElement(Unknown Source) at org.apache.xerces.impl.XMLDocumentFragmentScannerImpl$FragmentContentDispatcher.dispatch(Unknown Source) at org.apache.xerces.impl.XMLDocumentFragmentScannerImpl.scanDocument(Unknown Source) at org.apache.xerces.parsers.XML11Configuration.parse(Unknown Source) at org.apache.xerces.parsers.XML11Configuration.parse(Unknown Source) at org.apache.xerces.parsers.XMLParser.parse(Unknown Source) at org.apache.xerces.parsers.AbstractSAXParser.parse(Unknown Source) at org.apache.commons.digester.Digester.parse(Digester.java:1591) at org.apache.tiles.definition.digester.DigesterDefinitionsReader.read(DigesterDefinitionsReader.java:158) at org.apache.tiles.definition.UrlDefinitionsFactory.readDefinitions(UrlDefinitionsFactory.java:257) at org.apache.tiles.definition.UrlDefinitionsFactory.getComponentDefinitions(UrlDefinitionsFactory.java:116) at org.apache.tiles.definition.UrlDefinitionsFactory.getDefinition(UrlDefinitionsFactory.java:136) at org.apache.tiles.impl.BasicTilesContainer.getDefinition(BasicTilesContainer.java:463) at org.apache.tiles.impl.BasicTilesContainer.render(BasicTilesContainer.java:363) at org.apache.tiles.impl.BasicTilesContainer.render(BasicTilesContainer.java:345) at org.apache.struts2.views.tiles.TilesResult.doExecute(TilesResult.java:107) at org.apache.struts2.dispatcher.StrutsResultSupport.execute(StrutsResultSupport.java:178) at com.opensymphony.xwork2.DefaultActionInvocation.executeResult(DefaultActionInvocation.java:343) and immediately with the following exceptions: 2010-04-08 05:51:09,970 ERROR [http-443-Processor38] ? - ApplicationSessionAwareInterceptor: org.apache.tiles.definition.DefinitionsFactoryException: XML error reading definitions. at org.apache.tiles.definition.digester.DigesterDefinitionsReader.read(DigesterDefinitionsReader.java:161) at org.apache.tiles.definition.UrlDefinitionsFactory.readDefinitions(UrlDefinitionsFactory.java:257) at org.apache.tiles.definition.UrlDefinitionsFactory.getComponentDefinitions(UrlDefinitionsFactory.java:116) at org.apache.tiles.definition.UrlDefinitionsFactory.getDefinition(UrlDefinitionsFactory.java:136) at org.apache.tiles.impl.BasicTilesContainer.getDefinition(BasicTilesContainer.java:463) at org.apache.tiles.impl.BasicTilesContainer.render(BasicTilesContainer.java:363) at org.apache.tiles.impl.BasicTilesContainer.render(BasicTilesContainer.java:345) at org.apache.struts2.views.tiles.TilesResult.doExecute(TilesResult.java:107) at org.apache.struts2.dispatcher.StrutsResultSupport.execute(StrutsResultSupport.java:178) at com.opensymphony.xwork2.DefaultActionInvocation.executeResult(DefaultActionInvocation.java:343) Both exceptions are from DigesterDefinitionsReader.java and root cause for the second one is "org.xml.sax.SAXException: FWK005 parse may not be called while parsing.". Tiles is using Xerces parser to parse tiles definition, but DocumentBuilder is not thread safe and it seems Tiles doesn't do synchronization, which caused the problem. I have changed DigesterDefinitionsReader.java and added a synchronized block in read(Object source) method and the problems seems have went away. I am wondering if anyone saw the same issue and is this a Tiles bug? Besides, why Tiles keep reading the same file? Boxiong