Page History

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• Wiki Markup
  Classloader HOWTO pages: \[http://tomcat.apache.org/tomcat-4.1-doc/class-loader-howto.html Tomcat 4.1\], \[http://tomcat.apache.org/tomcat-5.05-doc/class-loader-howto.html Tomcat 5.05\], \[http://tomcat.apache.org/tomcat-56.50-doc/class-loader-howto.html Tomcat 56.50\].

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  \[http://marc.theaimsgroup.com/?t=104317529200004&r=1&w=2 Don't\] \[http://marc.theaimsgroup.com/?t=104380440100003&r=1&w=2 use\] \[http://marc.theaimsgroup.com/?t=96947656900002&r=1&w=2 packageless\] \[http://marc.theaimsgroup.com/?t=104491020100002&r=1&w=2 classes\] \[http://marc.theaimsgroup.com/?t=104265576200003&r=1&w=2 and\] \[http://marc.theaimsgroup.com/?t=104249748300001&r=1&w=2 declare\] \[http://marc.theaimsgroup.com/?t=102996950100003&r=1&w=2 all\] \[http://marc.theaimsgroup.com/?t=102922189400001&r=1&w=2 imported classes\]!

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  \[http://marc.theaimsgroup.com/?l=tomcat-user&m=103843452413727&w=2 Another answer to a classloader issue\] \\

If you get a NoClassDefFoundError exception, the root cause might be the same as for a ClassNotFound exception.

Questions

1. Wiki Markup
   \[#Q1 Why is jsp:useBean is not working?\]

2. Wiki Markup
   \[#Q2 Why do I get java.lang.NoClassDefFoundError: javax/servlet/Filter?\]

3. Wiki Markup
   \[#Q3 Why do I get java.lang.NoClassDefFoundError: org/xml/sax/InputSource?\] \\

Answers

*Why is

 jsp:useBean 

...

• Your bean is packaged in a class.
• You have fully qualified your class name (eg:

  No Format
  com.bar.package.MyClass

  ) OR
• You have imported your class into your jsp (eg:

  No Format
  <%@ pageimport="com.bar.package.MyClass"%>

  )
  

*Why do I get

 java.lang.NoClassDefFoundError: javax/servlet/Filter

?*

You probably have servlet.jar floating around somewhere it shouldn't be. This really messes up the classloaders since Tomcat's classloaders don't act quite as normal as one expects (see links above). servlet.jar should only be found only once in $CATALINA_HOME/common/lib.

*Why do I get

 java.lang.NoClassDefFoundError: org/xml/sax/InputSource 

?*

You have conflicting XML api jar files in your classpath. Read the README or RELEASE-NOTES for more information.