It's because Struts and JBoss don't play well together. They will for a while... until you really don't expect it, and you will spend a couple of days flossing the plaque from your configuration while trying to get it working again. Struts and JBoss are two of the dozen or so "must haves"... so they ought to be pretty robust together if you ask me.
If I had the knowledge to fix this problem, I would take a crack at it. GAWD I WOULD LOVE TO FIX THIS!!! I think the only way it will get fixed is if Scott and Craig were locked in a conference room until the problem was solved. There might be people that can fix it besides these two, but the solution undoubtedly is steeped in both architecture and politics, and these two are the only two that I can think of that have the noodle to make it happen and the "power of one" to lay down the new unified law of the landscape. Struts depends on a lot of libraries and is quite precise about it's specification of a class loader. I don't understand it all, but I gather that this precision makes it more portable in general. But I wonder whether Struts would work better under JBoss if it were more sloppy (using class.forName() instead of ClassLoader.loadClass() for instance...) JBoss, for all it's glory, tries to make all class loaders in a VM look like the same one, but they show their colors under very specific circumstances. Okay, I'm frustrated because I've burned up the last 24 hours on this. I guess I'm doing better than last time where it took something like a week to muddle through the problem. So I'll quit bitching now and tell you what I know. Maybe it will help, hopefully others can add more. My issue has to do with getting a class in WEB-INF/classes to be found by the validator in a call to getMethod.... I presume you are running on JBoss because you are using EJBs. It's easy for your classes and libraries to get co-mingled between the ejb.jar and web.war as a part of your build. Don't allow that. Go through and purge from each what is not necessary in the other. For instance, get all your entity classes out of the web.war... strictly "interfaces only" over there. Same is true for your web classes. They don't belong in the ejb container, get them out of there. Make absolutely sure that all the libraries that you are using are of the same version. A good way to find them is to do a file system search in both JBoss' temp directory and the Catalina temp directory to see if the jars are exactly the same version. If they are not necessary on one or the other side, remove them as appropriate. JBoss tries to be smart with sharing your jars within a VM, but JBoss seems all to happy to let an app be very specific about where a jar comes from, and when it does, it seems to cut off all the other linkages to the other libraries in the transitive closure of the load chain. Again, I don't understand it all, and generally call in a witch doctor with a rooster and two chickens for a sacrifice over the keyboard. After praising Chairman Bill and Lou Cipher as soulmates and a dab of sacred balm on the forehead, things start to work again, but only if the moon is just right. It's all about this scientific, so have fun. I bet you can solve the problem with these tricks. When trying to reproduce a problem though, always blow away your temp directories with each iteration or you are asking for enhanced humiliation and pain. I know that is precisely what you don't want to do, but because it works when you do that and does not when you don't that the problem is in the load order of the libraries being different from load-to-load and two libraries are in the path that are different versions. They won't even look like they are relevant, but clean them up anyway, they could be on the transitive closure of the runtime link. hth, -b -----Original Message----- From: Matthew Van Horn [mailto:[EMAIL PROTECTED] Sent: Tuesday, March 04, 2003 12:09 AM To: Struts Users Mailing List; [EMAIL PROTECTED] Subject: need help with struts error I get the following error whenever I deploy an .ear file, but if I just stop and start JBoss the file is picked up and deploys fine. If I then touch the file, I get the error again. What gives? The best I can find with google is that it may have something to do with the DTD going missing, or another parser being there, but neither of those seems to be the case. 17:02:59,730 ERROR [ActionServlet] Parsing error processing resource path /WEB-INF/struts-config.xml java.lang.LinkageError: loader constraints violated when linking org/apache/commons/digester/ObjectCreationFactory class at org.apache.struts.config.ConfigRuleSet.addRuleInstances(ConfigRuleSet.ja va:121) at org.apache.commons.digester.Digester.addRuleSet(Digester.java:1610) at org.apache.struts.action.ActionServlet.initConfigDigester(ActionServlet. java:1211) at org.apache.struts.action.ActionServlet.initModuleConfig(ActionServlet.ja va:923) at org.apache.struts.action.ActionServlet.init(ActionServlet.java:468) at javax.servlet.GenericServlet.init(GenericServlet.java:256) at org.apache.catalina.core.StandardWrapper.loadServlet(StandardWrapper.jav a:924) at org.apache.catalina.core.StandardWrapper.load(StandardWrapper.java:813) at org.apache.catalina.core.StandardContext.loadOnStartup(StandardContext.j ava:3341) at org.apache.catalina.core.StandardContext.start(StandardContext.java:3534 ) at org.apache.catalina.core.ContainerBase.addChildInternal(ContainerBase.ja va:821) at org.apache.catalina.core.ContainerBase.addChild(ContainerBase.java:807) at org.apache.catalina.core.StandardHost.addChild(StandardHost.java:579) at org.jboss.web.catalina.EmbeddedCatalinaService41.createWebContext(Embedd edCatalinaService41.java:432) at org.jboss.web.catalina.EmbeddedCatalinaService41.performDeploy(EmbeddedC atalinaService41.java:306) at org.jboss.web.AbstractWebContainer.start(AbstractWebContainer.java:300) at org.jboss.deployment.MainDeployer.start(MainDeployer.java:807) at org.jboss.deployment.MainDeployer.start(MainDeployer.java:799) at org.jboss.deployment.MainDeployer.deploy(MainDeployer.java:621) at org.jboss.deployment.MainDeployer.deploy(MainDeployer.java:585) at java.lang.reflect.Method.invoke(Native Method) at org.jboss.mx.capability.ReflectedMBeanDispatcher.invoke(ReflectedMBeanDi spatcher.java:284) at org.jboss.mx.server.MBeanServerImpl.invoke(MBeanServerImpl.java:517) at org.jboss.util.jmx.MBeanProxy.invoke(MBeanProxy.java:174) at $Proxy4.deploy(Unknown Source) at org.jboss.deployment.scanner.URLDeploymentScanner.deploy(URLDeploymentSc anner.java:435) at org.jboss.deployment.scanner.URLDeploymentScanner.scan(URLDeploymentScan ner.java:561) at org.jboss.deployment.scanner.AbstractDeploymentScanner$ScannerThread.doS can(AbstractDeploymentScanner.java:212) at org.jboss.deployment.scanner.AbstractDeploymentScanner$ScannerThread.loo p(AbstractDeploymentScanner.java:225) at org.jboss.deployment.scanner.AbstractDeploymentScanner$ScannerThread.run (AbstractDeploymentScanner.java:202) 17:03:00,005 INFO [Engine] StandardWrapper[/atjweb:action]: Marking servlet action as unavailable 17:03:00,039 ERROR [Engine] StandardContext[/atjweb]: Servlet /atjweb threw load() exception javax.servlet.UnavailableException: Parsing error processing resource path /WEB-INF/struts-config.xml at org.apache.struts.action.ActionServlet.initModuleConfig(ActionServlet.ja va:952) at org.apache.struts.action.ActionServlet.init(ActionServlet.java:468) at javax.servlet.GenericServlet.init(GenericServlet.java:256) at org.apache.catalina.core.StandardWrapper.loadServlet(StandardWrapper.jav a:924) at org.apache.catalina.core.StandardWrapper.load(StandardWrapper.java:813) at org.apache.catalina.core.StandardContext.loadOnStartup(StandardContext.j ava:3341) at org.apache.catalina.core.StandardContext.start(StandardContext.java:3534 ) at org.apache.catalina.core.ContainerBase.addChildInternal(ContainerBase.ja va:821) at org.apache.catalina.core.ContainerBase.addChild(ContainerBase.java:807) at org.apache.catalina.core.StandardHost.addChild(StandardHost.java:579) at org.jboss.web.catalina.EmbeddedCatalinaService41.createWebContext(Embedd edCatalinaService41.java:432) at org.jboss.web.catalina.EmbeddedCatalinaService41.performDeploy(EmbeddedC atalinaService41.java:306) at org.jboss.web.AbstractWebContainer.start(AbstractWebContainer.java:300) at org.jboss.deployment.MainDeployer.start(MainDeployer.java:807) at org.jboss.deployment.MainDeployer.start(MainDeployer.java:799) at org.jboss.deployment.MainDeployer.deploy(MainDeployer.java:621) at org.jboss.deployment.MainDeployer.deploy(MainDeployer.java:585) at java.lang.reflect.Method.invoke(Native Method) at org.jboss.mx.capability.ReflectedMBeanDispatcher.invoke(ReflectedMBeanDi spatcher.java:284) at org.jboss.mx.server.MBeanServerImpl.invoke(MBeanServerImpl.java:517) at org.jboss.util.jmx.MBeanProxy.invoke(MBeanProxy.java:174) at $Proxy4.deploy(Unknown Source) at org.jboss.deployment.scanner.URLDeploymentScanner.deploy(URLDeploymentSc anner.java:435) at org.jboss.deployment.scanner.URLDeploymentScanner.scan(URLDeploymentScan ner.java:561) at org.jboss.deployment.scanner.AbstractDeploymentScanner$ScannerThread.doS can(AbstractDeploymentScanner.java:212) at org.jboss.deployment.scanner.AbstractDeploymentScanner$ScannerThread.loo p(AbstractDeploymentScanner.java:225) at org.jboss.deployment.scanner.AbstractDeploymentScanner$ScannerThread.run (AbstractDeploymentScanner.java:202) --------------------------------------------------------------------- To unsubscribe, e-mail: [EMAIL PROTECTED] For additional commands, e-mail: [EMAIL PROTECTED] --------------------------------------------------------------------- To unsubscribe, e-mail: [EMAIL PROTECTED] For additional commands, e-mail: [EMAIL PROTECTED]
