javax.servlet.ServletException: Error allocating a servlet instance

[Ajay Njallacattu]

Hi,

We are getting the following exception when we try to run a web application in Apache Tomcat.

javax.servlet.ServletException: Error allocating a servlet instance
org.apache.catalina.valves.ErrorReportValve.invoke(ErrorReportValve.java:105)
org.apache.catalina.connector.CoyoteAdapter.service(CoyoteAdapter.java:148)
org.apache.coyote.http11.Http11Processor.process(Http11Processor.java:869)
org.apache.coyote.http11.Http11BaseProtocol$Http11ConnectionHandler.processConnection(Http11BaseProtocol.java:664)
org.apache.tomcat.util.net.PoolTcpEndpoint.processSocket(PoolTcpEndpoint.java:527)
org.apache.tomcat.util.net.LeaderFollowerWorkerThread.runIt(LeaderFollowerWorkerThread.java:80)
org.apache.tomcat.util.threads.ThreadPool$ControlRunnable.run(ThreadPool.java:684)
java.lang.Thread.run(Thread.java:595)
root cause

java.lang.UnsupportedClassVersionError: Bad version number in .class file
java.lang.ClassLoader.defineClass1(Native Method)
java.lang.ClassLoader.defineClass(ClassLoader.java:620)
java.security.SecureClassLoader.defineClass(SecureClassLoader.java:124)
org.apache.catalina.loader.WebappClassLoader.findClassInternal(WebappClassLoader.java:1815)
org.apache.catalina.loader.WebappClassLoader.findClass(WebappClassLoader.java:869)
org.apache.catalina.loader.WebappClassLoader.loadClass(WebappClassLoader.java:1322)
org.apache.catalina.loader.WebappClassLoader.loadClass(WebappClassLoader.java:1201)
org.apache.catalina.valves.ErrorReportValve.invoke(ErrorReportValve.java:105)
org.apache.catalina.connector.CoyoteAdapter.service(CoyoteAdapter.java:148)
org.apache.coyote.http11.Http11Processor.process(Http11Processor.java:869)
org.apache.coyote.http11.Http11BaseProtocol$Http11ConnectionHandler.processConnection(Http11BaseProtocol.java:664)
org.apache.tomcat.util.net.PoolTcpEndpoint.processSocket(PoolTcpEndpoint.java:527)
org.apache.tomcat.util.net.LeaderFollowerWorkerThread.runIt(LeaderFollowerWorkerThread.java:80)
org.apache.tomcat.util.threads.ThreadPool$ControlRunnable.run(ThreadPool.java:684)
java.lang.Thread.run(Thread.java:595)

Regards
Ajay

[Jeff Ishar]

java.lang.UnsupportedClassVersionError: Bad version number in .class file 

This is due to difference between JDK versions, the java source was compiled with other JDK version then tomcat is running on. Try to match the JDK version on both server and development machine (where classes are generated). Once tomcat try to load the servlet class with classloader from JDK 6 (for ex) but the classes were compile with JDK 5, it will through the above exception and after that the rest of exception will be thrown.



Hope this helps

[Ajay Njallacattu]

Hi,

We have matched the JDK for the development and deployment. Still we are getting the same issue.

Is there anything else we need to do get this working?


Regards

Ajay

[Jeff Ishar]

After matching the JDK, did you recompile the classes and build the war file and redeploy it ? Restart the tomcat? What version you are running the server on?

thanks

[Ajay Njallacattu]

All,

The issue was with respect to the different JDK versions.

Thanks a lot for all the inputs..


Regards

Ajay