Re: Tomcat Filter with RequestDispatcher - IncompatibleClassChangeError
Ok, after further investigating, I realize I must have screwed up my Tomcat installation somewhere along the line because a Request Dispatcher that worked several months ago no longer works and give the same errors below. Based on this, I can rule out the Filter code being wrong and turn my attention to stuff I recently added. The prime suspect as always is the xml libraries. Would this affect it ? I hate the fact that adding JAXP to my system breaks some Tomcat things. Recently I added JAXP which means that I now have in tomcat/common/lib, - activation.jar - dom.jar - jaxp-api.jar - jdbc2_0_stdext.jar - jndi.jar - jta.jar - ldap.jar - mail.jar - mysql.jar - naming-common.jar - naming-resources.jar - sax.jar - servlet.jar - tools.jar - tyrex-0.9.7.0.jar - xalan.jar - xercesImpl.jar - xsltc.jar and in tomcat/jasper I have, - crimson.jar - jasper-compiler.jar - jaxp.jar In order to install JAXP I had to remove 'jaxp-api.jar' from tomcat/jasper Could any of this be the cause, or should I really look at just reinstalling the latest stable version of Tomcat4 ? If it helps, my classpath includes, commons-beanutils.jar; (jakarta) commons-collections.jar; (jakarta) jakarta-oro-2.0.6.jar; (jakarta) commons-digester.jar;(jakarta) commons-logging.jar; (jakarta) velocity-J2EE-dep-1.3-rc1.jar; activation.jar; (javamail) mail.jar;(javamail) tomcat_home\common\lib\servlet.jar; dom.jar; (jaxp) jaxp-api.jar; (jaxp) sax.jar; (jaxp) xalan.jar;(jaxp) xercesImpl.jar; (jaxp) xsltc.jar;(jaxp) turbine-2.2-b2-dev.jar; (jetspeed) jetspeed-1.4b1.jar; (jetspeed) ecs-1.4.1.jar;(jetspeed) but things in the classpath shouldn't affect Tomcat, I think. Stephen Stephen Riek [EMAIL PROTECTED] wrote: Thanks for the reply, Craig. Error Trace --- java.lang.IncompatibleClassChangeError This exception normally means you have made a change in a superclass and recompiled it, but not recompiled a subclass that depends on the old APIs. m, I have no idea which class this could be referring to then, unless it means one of Tomcat's distribution classes. To further debug, I removed ALL other classes under WEB-INF/classes, so that I only have my one Filter there. I also removed all jars from WEB-INF/lib, then restarted Tomcat. Therefore, the only superclass involved is the Filter class. I recompiled my LanguageFilter.java and yet the error still occured. at mas.TestFilter.doFilter(Store/LanguageFilter.java:35) What is Store? Is that supposed to be the package name? Sorry, yes, I copied an earlier/older trace. You should recompile *all* your classes to catch any cases where you've made incompatible changes. I've done exactly that now (basically due to the fact that I only have the ONE class - the LanguageFilter.java) I have even deleted the entire contents of the /work directory and restarted Tomcat again to ensure that it is not an old class being cached in memory. Interestingly, the very first time that I make a request to the Filter, I get the following error message: java.lang.LinkageError: Class javax/servlet/RequestDispatcher violates loader constraints at test.LanguageFilter.doFilter(test/LanguageFilter.java:36) at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:213) at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:193) at org.apache.catalina.core.StandardWrapperValve.invoke(StandardWrapperValve.java:243) at org.apache.catalina.core.StandardPipeline.invokeNext(StandardPipeline.java:566) at org.apache.catalina.core.StandardPipeline.invoke(StandardPipeline.java:472) at org.apache.catalina.core.ContainerBase.invoke(ContainerBase.java:943) at org.apache.catalina.core.StandardContextValve.invoke(StandardContextValve.java:215) at org.apache.catalina.core.StandardPipeline.invokeNext(StandardPipeline.java:566) at org.apache.catalina.authenticator.AuthenticatorBase.invoke(AuthenticatorBase.java:472) at org.apache.catalina.core.StandardPipeline.invokeNext(StandardPipeline.java:564) at org.apache.catalina.core.StandardPipeline.invoke(StandardPipeline.java:472) at org.apache.catalina.core.ContainerBase.invoke(ContainerBase.java:943) Yet when I hit reload the error message changes to: java.lang.IncompatibleClassChangeError at test.LanguageFilter.doFilter(test/LanguageFilter.java:36) at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:213) at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:193) at org.apache.catalina.core.StandardWrapperValve.invoke(StandardWrapperValve.java:243) at org.apache.catalina.core.StandardPipeline.invokeNext(StandardPipeline.java:566) at org.apache.catalina.core.StandardPipeline.invoke(StandardPipeline.java:472) at
Re: Tomcat Filter with RequestDispatcher - IncompatibleClassChangeError
Dear Stephen, You got to remove your xerces.jar from the classpath. This one should be conflicting with your existing jaxp classes. I had this problem when i moved xerces.jar into the classpath and i couldnt able to run my files. Hope this helps. karthikeyan. - Original Message - From: Stephen Riek [EMAIL PROTECTED] To: Tomcat Users List [EMAIL PROTECTED] Sent: Wednesday, November 27, 2002 2:54 PM Subject: Re: Tomcat Filter with RequestDispatcher - IncompatibleClassChangeError Ok, after further investigating, I realize I must have screwed up my Tomcat installation somewhere along the line because a Request Dispatcher that worked several months ago no longer works and give the same errors below. Based on this, I can rule out the Filter code being wrong and turn my attention to stuff I recently added. The prime suspect as always is the xml libraries. Would this affect it ? I hate the fact that adding JAXP to my system breaks some Tomcat things. Recently I added JAXP which means that I now have in tomcat/common/lib, - activation.jar - dom.jar - jaxp-api.jar - jdbc2_0_stdext.jar - jndi.jar - jta.jar - ldap.jar - mail.jar - mysql.jar - naming-common.jar - naming-resources.jar - sax.jar - servlet.jar - tools.jar - tyrex-0.9.7.0.jar - xalan.jar - xercesImpl.jar - xsltc.jar and in tomcat/jasper I have, - crimson.jar - jasper-compiler.jar - jaxp.jar In order to install JAXP I had to remove 'jaxp-api.jar' from tomcat/jasper Could any of this be the cause, or should I really look at just reinstalling the latest stable version of Tomcat4 ? If it helps, my classpath includes, commons-beanutils.jar; (jakarta) commons-collections.jar; (jakarta) jakarta-oro-2.0.6.jar; (jakarta) commons-digester.jar;(jakarta) commons-logging.jar; (jakarta) velocity-J2EE-dep-1.3-rc1.jar; activation.jar; (javamail) mail.jar;(javamail) tomcat_home\common\lib\servlet.jar; dom.jar; (jaxp) jaxp-api.jar; (jaxp) sax.jar; (jaxp) xalan.jar;(jaxp) xercesImpl.jar; (jaxp) xsltc.jar;(jaxp) turbine-2.2-b2-dev.jar; (jetspeed) jetspeed-1.4b1.jar; (jetspeed) ecs-1.4.1.jar;(jetspeed) but things in the classpath shouldn't affect Tomcat, I think. Stephen Stephen Riek [EMAIL PROTECTED] wrote: Thanks for the reply, Craig. Error Trace --- java.lang.IncompatibleClassChangeError This exception normally means you have made a change in a superclass and recompiled it, but not recompiled a subclass that depends on the old APIs. m, I have no idea which class this could be referring to then, unless it means one of Tomcat's distribution classes. To further debug, I removed ALL other classes under WEB-INF/classes, so that I only have my one Filter there. I also removed all jars from WEB-INF/lib, then restarted Tomcat. Therefore, the only superclass involved is the Filter class. I recompiled my LanguageFilter.java and yet the error still occured. at mas.TestFilter.doFilter(Store/LanguageFilter.java:35) What is Store? Is that supposed to be the package name? Sorry, yes, I copied an earlier/older trace. You should recompile *all* your classes to catch any cases where you've made incompatible changes. I've done exactly that now (basically due to the fact that I only have the ONE class - the LanguageFilter.java) I have even deleted the entire contents of the /work directory and restarted Tomcat again to ensure that it is not an old class being cached in memory. Interestingly, the very first time that I make a request to the Filter, I get the following error message: java.lang.LinkageError: Class javax/servlet/RequestDispatcher violates loader constraints at test.LanguageFilter.doFilter(test/LanguageFilter.java:36) at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(Application FilterChain.java:213) at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterCh ain.java:193) at org.apache.catalina.core.StandardWrapperValve.invoke(StandardWrapperValve.ja va:243) at org.apache.catalina.core.StandardPipeline.invokeNext(StandardPipeline.java:5 66) at org.apache.catalina.core.StandardPipeline.invoke(StandardPipeline.java:472) at org.apache.catalina.core.ContainerBase.invoke(ContainerBase.java:943) at org.apache.catalina.core.StandardContextValve.invoke(StandardContextValve.ja va:215) at org.apache.catalina.core.StandardPipeline.invokeNext(StandardPipeline.java:5 66) at org.apache.catalina.authenticator.AuthenticatorBase.invoke(AuthenticatorBase .java:472) at org.apache.catalina.core.StandardPipeline.invokeNext(StandardPipeline.java:5 64) at org.apache.catalina.core.StandardPipeline.invoke(StandardPipeline.java:472) at org.apache.catalina.core.ContainerBase.invoke(ContainerBase.java:943) Yet when I hit reload the error message changes
RE: Tomcat Filter with RequestDispatcher - IncompatibleClassChangeError
what you compile against and what tomcat is using *could* be two different things if your classpath is not identical to /common/lib(and WEB-INF/lib), which it looks like yours is very different. Therefore if your class was compiled against some library that contains a different version of any classes(i.e. older/newer xerces) than tomcat is running then you could have an incompatibility like that. Tomcat ignores the classpath, so apparently you did compile against an newer version of xerces. If you need this newer version, replace the one in /tomcat/lib. Charlie -Original Message- From: Stephen Riek [mailto:[EMAIL PROTECTED]] Sent: Wednesday, November 27, 2002 6:02 AM To: Tomcat Users List Subject: Re: Tomcat Filter with RequestDispatcher - IncompatibleClassChangeError Dear Karthikeyan, I would have been willing to bet almost anything that your suggestion would not work. And I would have lost badly. Thank you indeed, I removed all the JAXP stuff (including Xerces.jar) from my classpath and now the Filters work fine. Why on earth this should work is beyond me. I thought that Tomcat had its own classloader and would use its own packages instead of those on the classpath. This also leaves me wondering how I'm supposed to go about compiling all of my classes that use XML/JAXP on my machine, now that I've removed it all. If only everybody used the same XML libraries it would be much easier. Thanks again, you've made my day. Stephen. karthikeyan.balasubramanian [EMAIL PROTECTED] wrote:Dear Stephen, You got to remove your xerces.jar from the classpath. This one should be conflicting with your existing jaxp classes. I had this problem when i moved xerces.jar into the classpath and i couldnt able to run my files. Hope this helps. karthikeyan. - Original Message - From: Stephen Riek To: Tomcat Users List Sent: Wednesday, November 27, 2002 2:54 PM Subject: Re: Tomcat Filter with RequestDispatcher - IncompatibleClassChangeError Ok, after further investigating, I realize I must have screwed up my Tomcat installation somewhere along the line because a Request Dispatcher that worked several months ago no longer works and give the same errors below. Based on this, I can rule out the Filter code being wrong and turn my attention to stuff I recently added. The prime suspect as always is the xml libraries. Would this affect it ? I hate the fact that adding JAXP to my system breaks some Tomcat things. Recently I added JAXP which means that I now have in /common/lib, - activation.jar - dom.jar - jaxp-api.jar - jdbc2_0_stdext.jar - jndi.jar - jta.jar - ldap.jar - mail.jar - mysql.jar - naming-common.jar - naming-resources.jar - sax.jar - servlet.jar - tools.jar - tyrex-0.9.7.0.jar - xalan.jar - xercesImpl.jar - xsltc.jar and in /jasper I have, - crimson.jar - jasper-compiler.jar - jaxp.jar In order to install JAXP I had to remove 'jaxp-api.jar' from /jasper Could any of this be the cause, or should I really look at just reinstalling the latest stable version of Tomcat4 ? If it helps, my classpath includes, commons-beanutils.jar; (jakarta) commons-collections.jar; (jakarta) jakarta-oro-2.0.6.jar; (jakarta) commons-digester.jar; (jakarta) commons-logging.jar; (jakarta) velocity-J2EE-dep-1.3-rc1.jar; activation.jar; (javamail) mail.jar; (javamail) \common\lib\servlet.jar; dom.jar; (jaxp) jaxp-api.jar; (jaxp) sax.jar; (jaxp) xalan.jar; (jaxp) xercesImpl.jar; (jaxp) xsltc.jar; (jaxp) turbine-2.2-b2-dev.jar; (jetspeed) jetspeed-1.4b1.jar; (jetspeed) ecs-1.4.1.jar; (jetspeed) but things in the classpath shouldn't affect Tomcat, I think. Stephen Stephen Riek wrote: Thanks for the reply, Craig. Error Trace --- java.lang.IncompatibleClassChangeError This exception normally means you have made a change in a superclass and recompiled it, but not recompiled a subclass that depends on the old APIs. m, I have no idea which class this could be referring to then, unless it means one of Tomcat's distribution classes. To further debug, I removed ALL other classes under WEB-INF/classes, so that I only have my one Filter there. I also removed all jars from WEB-INF/lib, then restarted Tomcat. Therefore, the only superclass involved is the Filter class. I recompiled my LanguageFilter.java and yet the error still occured. at mas.TestFilter.doFilter(Store/LanguageFilter.java:35) What is Store? Is that supposed to be the package name? Sorry, yes, I copied an earlier/older trace. You should recompile *all* your classes to catch any cases where you've made incompatible changes. I've done exactly that now (basically due to the fact that I only have the ONE class - the LanguageFilter.java) I have even deleted the entire contents
RE: Tomcat Filter with RequestDispatcher - IncompatibleClassChangeError
This also leaves me wondering how I'm supposed to go about compiling all of my classes that use XML/JAXP on my machine, now that I've removed it all. I've been learning about Ant recently. Perhaps it can help you in this respect. Erik -- To unsubscribe, e-mail: mailto:[EMAIL PROTECTED] For additional commands, e-mail: mailto:[EMAIL PROTECTED]
Re: Tomcat Filter with RequestDispatcher - IncompatibleClassChangeError
On Wed, 27 Nov 2002, Stephen Riek wrote: java.lang.LinkageError: Class javax/servlet/RequestDispatcher violates loader constraints Sounds like you might have servlet.jar in your /WEB-INF directory, or in your JDK extensions directory. Don't do that. Craig -- To unsubscribe, e-mail: mailto:[EMAIL PROTECTED] For additional commands, e-mail: mailto:[EMAIL PROTECTED]
Re: Tomcat Filter with RequestDispatcher - IncompatibleClassChangeError
See below.
On Wed, 27 Nov 2002, Stephen Riek wrote:
Date: Wed, 27 Nov 2002 05:55:11 + (GMT)
From: Stephen Riek [EMAIL PROTECTED]
Reply-To: Tomcat Users List [EMAIL PROTECTED]
To: Tomcat Users List [EMAIL PROTECTED]
Subject: Tomcat Filter with RequestDispatcher -
IncompatibleClassChangeError
I've been at this for the better half of a day already
without joy. Am trying to create a Filter which accepts
a request for /fr/Products/Toys/index.jsp and forwards
the request to /Products/Toys/index.jsp after setting
an attribute lang to fr.
However, no matter what I try, the following error is
produced: java.lang.IncompatibleClassChangeError.
I have tested the URL /Products/Toys/index.jsp directly
in a browser and there is no problem with it, and using
System.out.println calls, I have deduced that the error
lies in the rd.forward(request, response) line.
Does anybody have any idea why this may be happening?
I'm using Tomcat4.0
Filter Source Code
--
public final class LanguageFilter implements Filter {
private FilterConfig filterConfig = null;
public void init(FilterConfig filterConfig) {
this.filterConfig = filterConfig;
}
public void doFilter(ServletRequest request, ServletResponse response, FilterChain
chain) throws IOException, ServletException {
String servletPath = ((HttpServletRequest) request).getServletPath();
// If path starts with /fr/, set the lang to fr.
if (servletPath.indexOf(/fr/) == 0) {
request.setAttribute(lang, fr);
String targetURL = servletPath.substring(3);
You probably don't want to do this *unless* the path starts with /fr,
right?
System.out.println(targetURL = + targetURL);
RequestDispatcher rd = null;
ServletContext sc = this.filterConfig.getServletContext();
rd = sc.getRequestDispatcher(targetURL);
System.out.println(ok, RequestDispatcher created);
if (rd!=null) {
rd.forward(request, response);
return;
}
chain.doFilter(request, response);
}
Error Trace
---
java.lang.IncompatibleClassChangeError
This exception normally means you have made a change in a superclass and
recompiled it, but not recompiled a subclass that depends on the old APIs.
at mas.TestFilter.doFilter(Store/LanguageFilter.java:35)
What is Store? Is that supposed to be the package name?
You should recompile *all* your classes to catch any cases where you've
made incompatible changes.
at
org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:213)
at
org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:193)
at
org.apache.catalina.core.StandardWrapperValve.invoke(StandardWrapperValve.java:243)
at org.apache.catalina.core.StandardPipeline.invokeNext(StandardPipeline.java:566)
at org.apache.catalina.core.StandardPipeline.invoke(StandardPipeline.java:472)
at org.apache.catalina.core.ContainerBase.invoke(ContainerBase.java:943)
Thank you for helping,
Stephen.
Craig
--
To unsubscribe, e-mail: mailto:[EMAIL PROTECTED]
For additional commands, e-mail: mailto:[EMAIL PROTECTED]
Re: Tomcat Filter with RequestDispatcher - IncompatibleClassChangeError
Thanks for the reply, Craig.
Error Trace
---
java.lang.IncompatibleClassChangeError
This exception normally means you have made a change in a superclass and
recompiled it, but not recompiled a subclass that depends on the old APIs.
m, I have no idea which class this could be referring
to then, unless it means one of Tomcat's distribution
classes. To further debug, I removed ALL other classes
under WEB-INF/classes, so that I only have my one Filter
there. I also removed all jars from WEB-INF/lib, then
restarted Tomcat. Therefore, the only superclass involved
is the Filter class.
I recompiled my LanguageFilter.java and yet the error
still occured.
at mas.TestFilter.doFilter(Store/LanguageFilter.java:35)
What is Store? Is that supposed to be the package name?
Sorry, yes, I copied an earlier/older trace.
You should recompile *all* your classes to catch any cases
where you've made incompatible changes.
I've done exactly that now (basically due to the fact that
I only have the ONE class - the LanguageFilter.java)
I have even deleted the entire contents of the tomcat_home/work
directory and restarted Tomcat again to ensure that it
is not an old class being cached in memory.
Interestingly, the very first time that I make a request to
the Filter, I get the following error message:
snip
java.lang.LinkageError: Class javax/servlet/RequestDispatcher violates loader
constraints
at test.LanguageFilter.doFilter(test/LanguageFilter.java:36)
at
org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:213)
at
org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:193)
at org.apache.catalina.core.StandardWrapperValve.invoke(StandardWrapperValve.java:243)
at org.apache.catalina.core.StandardPipeline.invokeNext(StandardPipeline.java:566)
at org.apache.catalina.core.StandardPipeline.invoke(StandardPipeline.java:472)
at org.apache.catalina.core.ContainerBase.invoke(ContainerBase.java:943)
at org.apache.catalina.core.StandardContextValve.invoke(StandardContextValve.java:215)
at org.apache.catalina.core.StandardPipeline.invokeNext(StandardPipeline.java:566)
at
org.apache.catalina.authenticator.AuthenticatorBase.invoke(AuthenticatorBase.java:472)
at org.apache.catalina.core.StandardPipeline.invokeNext(StandardPipeline.java:564)
at org.apache.catalina.core.StandardPipeline.invoke(StandardPipeline.java:472)
at org.apache.catalina.core.ContainerBase.invoke(ContainerBase.java:943)
/snip
Yet when I hit reload the error message changes to:
snip
java.lang.IncompatibleClassChangeError
at test.LanguageFilter.doFilter(test/LanguageFilter.java:36)
at
org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:213)
at
org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:193)
at
org.apache.catalina.core.StandardWrapperValve.invoke(StandardWrapperValve.java:243)
at
org.apache.catalina.core.StandardPipeline.invokeNext(StandardPipeline.java:566)
at org.apache.catalina.core.StandardPipeline.invoke(StandardPipeline.java:472)
at org.apache.catalina.core.ContainerBase.invoke(ContainerBase.java:943)
at
org.apache.catalina.core.StandardContextValve.invoke(StandardContextValve.java:215)
at
org.apache.catalina.core.StandardPipeline.invokeNext(StandardPipeline.java:566)
at
org.apache.catalina.authenticator.AuthenticatorBase.invoke(AuthenticatorBase.java:472)
at
org.apache.catalina.core.StandardPipeline.invokeNext(StandardPipeline.java:564)
at org.apache.catalina.core.StandardPipeline.invoke(StandardPipeline.java:472)
at org.apache.catalina.core.ContainerBase.invoke(ContainerBase.java:943)
at org.apache.catalina.core.StandardContext.invoke(StandardContext.java:2366)
at
org.apache.catalina.core.StandardHostValve.invoke(StandardHostValve.java:164)
at
org.apache.catalina.core.StandardPipeline.invokeNext(StandardPipeline.java:566)
/snip
These error messages were created with this Filter code
and I've added the check you suggested in your earlier
reply.
snip
package test;
import java.io.*;
import javax.servlet.*;
import javax.servlet.http.*;
public final class LanguageFilter implements Filter {
private FilterConfig filterConfig = null;
public void init(FilterConfig filterConfig) {
this.filterConfig = filterConfig;
}
public void doFilter(ServletRequest request, ServletResponse response, FilterChain
chain) throws IOException, ServletException {
String servletPath = ((HttpServletRequest) request).getServletPath();
// If the first element is '/en/' or '/fr/' :
if (servletPath.indexOf(/en/) == 0 || servletPath.indexOf(/fr/) == 0) {
String lang = servletPath.substring(1,3);
request.setAttribute(lang, lang);
String targetURL = servletPath.substring(3);
System.out.println(targetURL);
