Hello, Thanks for your help I got it working by scrapping the custom classloader altogether and calling Class.forName() to retreive an instance of the desired class.
Thanks again! -----Original Message----- From: David Smith [mailto:[EMAIL PROTECTED] Sent: December 8, 2005 9:12 AM To: Tomcat Users List Subject: Re: Question concerning java.lang.NoClassDefFoundError: javax/servlet/ServletContext Ok. I won't pretend to know all the ramifications to using this ClassFinder class. To my limited understanding, it's a classloader working without knowledge of Tomcat's classloaders and designed to help you reference classes stored outside the webapp. As a test, try removing the ClassFinder class and moving a copy of these external classes to WEB-INF/classes of your webapp. If that works, you issue has to do with the way your independent classloader is ignoring Tomcat's classloader structure. Anyone else with more experience in custom classloaders care to comment on this? --David Armand Rock wrote: >I personally have not changed any classpath settings. The classes are build >using Eclipse SDK Version 3.1.1 with >the Tomcat plugin from sysdeo (3.1.0.beta). >I have noticed that the NoClassDefFoundError occurs on specific pages but >only the first time >the pages are loaded, everything else within the page works perfectly after >I reload the page. >In every instance that I have issues I'm using a Servlet which in turn makes >use of the ClassFinder, >it first calls a Java file (specific to the current command being run) >followed by a redirection to a Jsp. > >As for ClassFileFinder here is the code. I can't find where this code was >from but it was originally found online... >I usually leave credit information at the top but this particuliar class did >not contain any. > >public class ClassFileFinder extends ClassLoader >{ > List cpath = new LinkedList(); > Hashtable loadedClasses = new Hashtable(); > > public void addFile(File f) { > if(f.isDirectory() || (f.isFile() && f.canRead() && > > f.getName().endsWith(".jar"))) > cpath.add(f); > } > > public byte[] classData(String className) { > String cname = className.replace('.', File.separatorChar) + > ".class"; > Iterator it = cpath.iterator(); > while(it.hasNext()) { > File f = (File)it.next(); > try { > if(f.isDirectory()) { > File cFile = new File(f, cname); > if(cFile.isFile()) { > byte[] buf = new > byte[(int)cFile.length()]; > InputStream in = new > FileInputStream(cFile); > int off = 0, l; > while((l = in.read(buf, off, > buf.length - off)) > 0) { > off += l; > if(off >= buf.length) > break; > } > in.read(buf); > in.close(); > return buf; > } > > } else if (f.isFile()) { > JarFile jar = new JarFile(f); > JarEntry ent = jar.getJarEntry(cname); > if(ent != null) { > > byte[] buf = new > byte[(int)ent.getSize()]; > int off = 0, l; > InputStream in = > jar.getInputStream(ent); > while((l = in.read(buf, off, > buf.length - off)) > 0) { > off += l; > if(off >= buf.length) > break; > } > > in.close(); > return buf; > } > } > } catch (IOException e) { > > } > } > return null; > } > > public Class findClass(String className) throws ClassNotFoundException{ > if (loadedClasses.get(className)!=null) { > return Class.forName(className); > } > > loadedClasses.put(className, className); > > byte[] data = classData(className); > if(data == null) > return getParent().loadClass(className); > else > return defineClass(className,data,0, data.length); > } >} > >-----Original Message----- >From: David Smith [mailto:[EMAIL PROTECTED] >Sent: December 7, 2005 7:47 AM >To: Tomcat Users List >Subject: Re: Question concerning java.lang.NoClassDefFoundError: >javax/servlet/ServletContext > > > > ...and that servlet-api.jar from tomcat is in the path. > >You wouldn't happen to be messing with the classpath at all would you? >That will cause headaches. Best advise is to leave the classpath alone >and let tomcat's classloader hierarchy handle finding classes. > >Thought 2: Tell me more about this ClassFinder class. It's not a part >of Java's API and I'm wondering if it's not running it's own classloader >independant of tomcat's classloader mechanism. > >--David > >John Poley wrote: > > > >>Thank you for your comments thus far. >>I have been unable to solve my problem as well. I even went so far as >>to start with a machine with no development tools on it, downloading >>just the elements I required, and then trying to redeploy. I am >>fairly certain that there are no extra servlet jars anywhere, and that >>servlet-api.jar from tomcat is in the path. Still I face the >>java.lang.NoClassDefFoundError: javax/servlet/ServletContext error. I >>am using java 1.5.0_06 and and a 5.5 server. Well, trying to anyway! >>=) I'll place the error information at the very bottom of this email >>to avoid pushing down the previous responses too far. Any more ideas >>would be appreciated! >> >>----- Original Message ----- From: "Armand Rock" <[EMAIL PROTECTED]> >>To: "Tomcat Users List" <users@tomcat.apache.org> >>Sent: Tuesday, December 06, 2005 12:44 PM >>Subject: RE: Question concerning java.lang.NoClassDefFoundError: >>javax/servlet/ServletContext >> >> >> >> >>>Hello David, >>>I included all jar & zip files on my computer, including j2ee.jar and >>>I'm >>>still having the problem. >>>I have just noticed a weird behaviour though, if I try to reload the jsp >>>right after the jsp fails the first >>>time it seems to run without throwing the exception. If I restart >>>Tomcat >>>and try again the problem starts >>>again. I could get this to work in theory by forcing it to run >>>through the >>>code once on startup >>>but I shouldn't have to do that and I honestly would prefer getting >>>it to >>>work as it should. >>> >>>-----Original Message----- >>>From: David Smith [mailto:[EMAIL PROTECTED] >>>Sent: December 6, 2005 11:57 AM >>>To: Tomcat Users List >>>Subject: Re: Question concerning java.lang.NoClassDefFoundError: >>>javax/servlet/ServletContext >>> >>> >>>I take it you also included j2ee.jar in that search? >>> >>>--David >>> >>>Armand Rock wrote: >>> >>> >>> >>>>Hi, >>>>I'm getting the same error. I searched my entire computer for any >>>>jar/zip >>>>files containing javax.servlet.ServletContext >>>>and renamed all of them to ".original" so that they wouldn't be read >>>>by the >>>>JVM. I did this to all the files except for the file >>>>common/lib/servlet-api.jar >>>> >>>>I'm still getting the problem. >>>> >>>>I'm using java version 1.4.2_10 >>>> >>>>The code i'm using used to work under Orion version 1.4.5 (I'm now >>>>using >>>>Tomcat 5.5) >>>>The code that eventually throws the exception is basically: >>>> >>>>ClassFinder classFinder = new ClassFinder(); >>>>classFinder.addFile("/opt/classes/com/canlink/commands/"); >>>>Class usrClass = >>>>classFinder.findClass("com.canlink.commands.TestClass"); >>>> >>>>This line is what throws the exception: >>>>Method setCmdLog = usrClass.getMethod("setCmdLog", new Class[] >>>>{Boolean.class}); >>>> >>>>The stack trace is: >>>>SEVERE: Servlet.service() for servlet RunCmd threw exception >>>>java.lang.NoClassDefFoundError: javax/servlet/ServletContext >>>>at java.lang.Class.getDeclaredMethods0(Native Method) >>>>at java.lang.Class.privateGetDeclaredMethods(Unknown Source) >>>>at java.lang.Class.getMethod0(Unknown Source) >>>>at java.lang.Class.getMethod0(Unknown Source) >>>>at java.lang.Class.getMethod(Unknown Source) >>>>at com.canlink.commands.RunCmd.service(RunCmd.java:240) >>>>at javax.servlet.http.HttpServlet.service(HttpServlet.java:802) >>>>at >>>> >>>> >>>> >org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(Applicatio > > >>>n >>> >>> >>> >>>>FilterChain.java:252) >>>>at >>>> >>>> >>>> >org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterC > > >>>h >>> >>> >>> >>>>ain.java:173) >>>>at >>>> >>>> >>>> >org.apache.catalina.core.ApplicationDispatcher.invoke(ApplicationDispatcher > > >>>. >>> >>> >>> >>>>java:672) >>>>at >>>> >>>> >>>> >org.apache.catalina.core.ApplicationDispatcher.processRequest(ApplicationDi > > >>>s >>> >>> >>> >>>>patcher.java:463) >>>>at >>>> >>>> >>>> >org.apache.catalina.core.ApplicationDispatcher.doForward(ApplicationDispatc > > >>>h >>> >>> >>> >>>>er.java:398) >>>>at >>>> >>>> >>>> >org.apache.catalina.core.ApplicationDispatcher.forward(ApplicationDispatche > > >>>r >>> >>> >>> >>>>.java:301) >>>>at org.apache.jsp.web.Login_jsp._jspService(Login_jsp.java:67) >>>>at org.apache.jasper.runtime.HttpJspBase.service(HttpJspBase.java:97) >>>>at javax.servlet.http.HttpServlet.service(HttpServlet.java:802) >>>>at >>>> >>>> >>>> >org.apache.jasper.servlet.JspServletWrapper.service(JspServletWrapper.java: > > >>>3 >>> >>> >>> >>>>22) >>>>at >>>> >>>> >>>org.apache.jasper.servlet.JspServlet.serviceJspFile(JspServlet.java:314) >>> >>> >>> >>>>at org.apache.jasper.servlet.JspServlet.service(JspServlet.java:264) >>>>at javax.servlet.http.HttpServlet.service(HttpServlet.java:802) >>>>at >>>> >>>> >>>> >org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(Applicatio > > >>>n >>> >>> >>> >>>>FilterChain.java:252) >>>>at >>>> >>>> >>>> >org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterC > > >>>h >>> >>> >>> >>>>ain.java:173) >>>>at >>>> >>>> >>>> >org.apache.catalina.core.StandardWrapperValve.invoke(StandardWrapperValve.j > > >>>a >>> >>> >>> >>>>va:213) >>>>at >>>> >>>> >>>> >org.apache.catalina.core.StandardContextValve.invoke(StandardContextValve.j > > >>>a >>> >>> >>> >>>>va:178) >>>>at >>>> >>>> >>>> >org.apache.catalina.core.StandardHostValve.invoke(StandardHostValve.java:12 > > >>>6 >>> >>> >>> >>>>) >>>>at >>>> >>>> >>>> >org.apache.catalina.valves.ErrorReportValve.invoke(ErrorReportValve.java:10 > > >>>5 >>> >>> >>> >>>>) >>>>at >>>> >>>> >>>> >org.apache.catalina.core.StandardEngineValve.invoke(StandardEngineValve.jav > > >>>a >>> >>> >>> >>>>:107) >>>>at >>>> >>>> >>>> >org.apache.catalina.connector.CoyoteAdapter.service(CoyoteAdapter.java:148) > > >>>>at >>>> >>>> >>>> >org.apache.coyote.http11.Http11Processor.process(Http11Processor.java:868) > > >>>>at >>>> >>>> >>>> >org.apache.coyote.http11.Http11BaseProtocol$Http11ConnectionHandler.process > > >>>C >>> >>> >>> >>>>onnection(Http11BaseProtocol.java:663) >>>>at >>>> >>>> >>>> >org.apache.tomcat.util.net.PoolTcpEndpoint.processSocket(PoolTcpEndpoint.ja > > >>>v >>> >>> >>> >>>>a:527) >>>>at >>>> >>>> >>>> >org.apache.tomcat.util.net.LeaderFollowerWorkerThread.runIt(LeaderFollowerW > > >>>o >>> >>> >>> >>>>rkerThread.java:80) >>>>at >>>> >>>> >>>> >org.apache.tomcat.util.threads.ThreadPool$ControlRunnable.run(ThreadPool.ja > > >>>v >>> >>> >>> >>>>a:684) >>>>at java.lang.Thread.run(Unknown Source) >>>> >>>>-----Original Message----- >>>>From: Tim Funk [mailto:[EMAIL PROTECTED] >>>>Sent: December 6, 2005 6:30 AM >>>>To: Tomcat Users List >>>>Subject: Re: Question concerning java.lang.NoClassDefFoundError: >>>>javax/servlet/ServletContext >>>> >>>> >>>>See - http://tomcat.apache.org/faq/classnotfound.html >>>> >>>>Odds are you have your own servlet-api.jar somewhere in the webapp or >>>> >>>> >>>system >>> >>> >>> >>>>classpath and that is conflicting with the one in common/lib >>>>(installed by >>>>tomcat) >>>> >>>>-Tim >>>> >>>>John Poley wrote: >>>> >>>> >>>> >>>> >>>>>Please forgive my intrusion if this is not the proper place to post a >>>>> >>>>> >>>>> >>>>> >>>>questoon of this sort. I am new to servlets, and am working on my >>>>first >>>>deployment- but I am running in to a problem that I can't find a >>>>solution >>>>to. I have installed Tomcat 5.5 and am using Eclipse (as well as a >>>>tomcat >>>>plugin) to manage my project. A colleague of mine sent me a war >>>>file of >>>>out working projected, which I imported to my IDE. I start tomcat, >>>>which >>>>seems to load properly, and attempt to run the project on the >>>>server- where >>>>I am faced with the following: >>>> >>>> >>>> >>>> >>>>>javax.servlet.ServletException: Servlet.init() for servlet >>>>> >>>>> >>>>> >>>>> >>>>RequestTranslator threw exception >>>> >>>> >>>> >>>> >>>>>root cause >>>>> >>>>>java.lang.NoClassDefFoundError: javax/servlet/ServletContext >>>>>java.lang.Class.getDeclaredConstructors0(Native Method) >>>>>java.lang.Class.privateGetDeclaredConstructors(Unknown Source) >>>>>java.lang.Class.getConstructor0(Unknown Source) >>>>>java.lang.Class.getConstructor(Unknown Source) >>>>> >>>>> >>>>> >>>>> >>>>> >freemarker.template.Configuration.setServletContextForTemplateLoading(Confi > > >>>g >>> >>> >>> >>>>uration.java:331) >>>> >>>> >>>> >>>> >>>> >verkoopen.boundary.UserInterfaceOutput.<init>(UserInterfaceOutput.java:31) > > >>>> >>>> >>>> >>>>>verkoopen.boundary.RequestTranslator.init(RequestTranslator.java:25) >>>>> >>>>> >>>>> >>>>> >>>>> >org.apache.catalina.valves.ErrorReportValve.invoke(ErrorReportValve.java:10 > > >>>5 >>> >>> >>> >>>>) >>>> >>>> >>>> >>>> >>>> >org.apache.catalina.connector.CoyoteAdapter.service(CoyoteAdapter.java:148) > > >>>> >>>> >>>> >>>> >org.apache.coyote.http11.Http11Processor.process(Http11Processor.java:868) > > >>>> >>>> >>>> >>>> >org.apache.coyote.http11.Http11BaseProtocol$Http11ConnectionHandler.process > > >>>C >>> >>> >>> >>>>onnection(Http11BaseProtocol.java:663) >>>> >>>> >>>> >>>> >>>> >org.apache.tomcat.util.net.PoolTcpEndpoint.processSocket(PoolTcpEndpoint.ja > > >>>v >>> >>> >>> >>>>a:527) >>>> >>>> >>>> >>>> >>>> >org.apache.tomcat.util.net.LeaderFollowerWorkerThread.runIt(LeaderFollowerW > > >>>o >>> >>> >>> >>>>rkerThread.java:80) >>>> >>>> >>>> >>>> >>>> >org.apache.tomcat.util.threads.ThreadPool$ControlRunnable.run(ThreadPool.ja > > >>>v >>> >>> >>> >>>>a:684) >>>> >>>> >>>> >>>> >>>>>java.lang.Thread.run(Unknown Source) >>>>>I am using the most recent J2RE 5 and I am certain that Tomcat's >>>>> >>>>> >>>>> >>>>> >>>>servlet-api.jar is within my application's class path. I am not >>>>sure why >>>>the source cannot be found. Any helpin locating my problem would be >>>> >>>> >>>greatly >>> >>> >>> >>>>appreciated, and I would be happy to prove more information if >>>>needed (I'm >>>>not entirely sure what would be helpful). And again, I am sorry if >>>>this is >>>>not the place for this kind of question!Happy coding!John >>>> >>>> >>>> >>>>--------------------------------------------------------------------- >>>>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] >>>> >>>> >>>> >>>> >>>> >>>--------------------------------------------------------------------- >>>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] >>> >>> >>> >> >> >>INFO: Server startup in 1891 ms >> >>Dec 6, 2005 9:59:25 PM org.apache.catalina.core.ApplicationContext log >> >>SEVERE: StandardWrapper.Throwable >> >>java.lang.NoClassDefFoundError: javax/servlet/ServletContext >> >>at java.lang.Class.getDeclaredConstructors0(Native Method) >> >>at java.lang.Class.privateGetDeclaredConstructors(Class.java:2328) >> >>at java.lang.Class.getConstructor0(Class.java:2640) >> >>at java.lang.Class.getConstructor(Class.java:1629) >> >>at >> >> >> >freemarker.template.Configuration.setServletContextForTemplateLoading(Confi g >uration.java:331) > > >>at >>verkoopen.boundary.UserInterfaceOutput.<init>(UserInterfaceOutput.java:31) >> >> >>at verkoopen.boundary.RequestTranslator.init(RequestTranslator.java:25) >> >>at >> >> >> >org.apache.catalina.core.StandardWrapper.loadServlet(StandardWrapper.java:1 1 >05) > > >>at >> >> >> >org.apache.catalina.core.StandardWrapper.allocate(StandardWrapper.java:757) > > >>at >> >> >> >org.apache.catalina.core.StandardWrapperValve.invoke(StandardWrapperValve.j a >va:130) > > >>at >> >> >> >org.apache.catalina.core.StandardContextValve.invoke(StandardContextValve.j a >va:178) > > >>at >> >> >> >org.apache.catalina.core.StandardHostValve.invoke(StandardHostValve.java:12 6 >) > > >>at >> >> >> >org.apache.catalina.valves.ErrorReportValve.invoke(ErrorReportValve.java:10 5 >) > > >>at >> >> >> >org.apache.catalina.core.StandardEngineValve.invoke(StandardEngineValve.jav a >:107) > > >>at >> >> >> >org.apache.catalina.connector.CoyoteAdapter.service(CoyoteAdapter.java:148) > > >>at >>org.apache.coyote.http11.Http11Processor.process(Http11Processor.java:869) >> >> >>at >> >> >> >org.apache.coyote.http11.Http11BaseProtocol$Http11ConnectionHandler.process C >onnection(Http11BaseProtocol.java:667) > > >>at >> >> >> >org.apache.tomcat.util.net.PoolTcpEndpoint.processSocket(PoolTcpEndpoint.ja v >a:527) > > >>at >> >> >> >org.apache.tomcat.util.net.LeaderFollowerWorkerThread.runIt(LeaderFollowerW o >rkerThread.java:80) > > >>at >> >> >> >org.apache.tomcat.util.threads.ThreadPool$ControlRunnable.run(ThreadPool.ja v >a:684) > > >>at java.lang.Thread.run(Thread.java:595) >> >> >> >>Dec 6, 2005 9:59:25 PM org.apache.catalina.core.StandardWrapperValve >>invoke >> >>SEVERE: Allocate exception for servlet RequestTranslator >> >>java.lang.NoClassDefFoundError: javax/servlet/ServletContext >> >>at java.lang.Class.getDeclaredConstructors0(Native Method) >> >>at java.lang.Class.privateGetDeclaredConstructors(Class.java:2328) >> >>at java.lang.Class.getConstructor0(Class.java:2640) >> >>at java.lang.Class.getConstructor(Class.java:1629) >> >>at >> >> >> >freemarker.template.Configuration.setServletContextForTemplateLoading(Confi g >uration.java:331) > > >>at >>verkoopen.boundary.UserInterfaceOutput.<init>(UserInterfaceOutput.java:31) >> >> >>at verkoopen.boundary.RequestTranslator.init(RequestTranslator.java:25) >> >>at >> >> >> >org.apache.catalina.core.StandardWrapper.loadServlet(StandardWrapper.java:1 1 >05) > > >>at >> >> >> >org.apache.catalina.core.StandardWrapper.allocate(StandardWrapper.java:757) > > >>at >> >> >> >org.apache.catalina.core.StandardWrapperValve.invoke(StandardWrapperValve.j a >va:130) > > >>at >> >> >> >org.apache.catalina.core.StandardContextValve.invoke(StandardContextValve.j a >va:178) > > >>at >> >> >> >org.apache.catalina.core.StandardHostValve.invoke(StandardHostValve.java:12 6 >) > > >>at >> >> >> >org.apache.catalina.valves.ErrorReportValve.invoke(ErrorReportValve.java:10 5 >) > > >>at >> >> >> >org.apache.catalina.core.StandardEngineValve.invoke(StandardEngineValve.jav a >:107) > > >>at >> >> >> >org.apache.catalina.connector.CoyoteAdapter.service(CoyoteAdapter.java:148) > > >>at >>org.apache.coyote.http11.Http11Processor.process(Http11Processor.java:869) >> >> >>at >> >> >> >org.apache.coyote.http11.Http11BaseProtocol$Http11ConnectionHandler.process C >onnection(Http11BaseProtocol.java:667) > > >>at >> >> >> >org.apache.tomcat.util.net.PoolTcpEndpoint.processSocket(PoolTcpEndpoint.ja v >a:527) > > >>at >> >> >> >org.apache.tomcat.util.net.LeaderFollowerWorkerThread.runIt(LeaderFollowerW o >rkerThread.java:80) > > >>at >> >> >> >org.apache.tomcat.util.threads.ThreadPool$ControlRunnable.run(ThreadPool.ja v >a:684) > > >>at java.lang.Thread.run(Thread.java:595) >> >>--------------------------------------------------------------------- >>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] > > > > >--------------------------------------------------------------------- >To unsubscribe, e-mail: [EMAIL PROTECTED] >For additional commands, e-mail: [EMAIL PROTECTED] > > > --------------------------------------------------------------------- To unsubscribe, e-mail: [EMAIL PROTECTED] 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