Tomcat6 and JRE7 compatibility issue. Unsupported major.minor version 51.0

Question

I have a web app compiled with JRE7 and now i'd like to run it on Tomcat6. When I launch my app I see exception in the logs:

Unsupported major.minor version 51.0
    at java.lang.ClassLoader.defineClass1(Native Method)
    at java.lang.ClassLoader.defineClassCond(ClassLoader.java:631)
    at java.lang.ClassLoader.defineClass(ClassLoader.java:615)
    at java.security.SecureClassLoader.defineClass(SecureClassLoader.java:141)

This exception comes from the class that implements ServletContextListener.

Does that mean I have to use Tomcat7 for code compiled with JRE7? Is there a workaround? Any information will be valuable.

possible duplicate http://stackoverflow.com/questions/9592791/tomcat6-and-java-7 — Sotirios Delimanolis, Jul 04 '13 at 21:07
It has nothing to do with Tomcat6. It's that you're attempting to run Java 7 bytecode with a Java 6 JVM. http://stackoverflow.com/questions/10382929/unsupported-major-minor-version-51-0 — Brian Roach, Jul 04 '13 at 21:13

score 5 · Accepted Answer · answered Jul 04 '13 at 22:00

5

You're attempting to run Java 7 bytecode with a Java 6. You need to deploy it to Tomcat 7 or recompile using JDK 1.6. Check what JRE your Tomcat uses. I guess it's Java 6 JVM.

answered Jul 04 '13 at 22:00

zacheusz

8,750
3
36
60

2

You are completely right, my catalina.sh file in JAVA_HOME had reference to 1.6 JDK. Thanks fo help! – Ihor M. Jul 04 '13 at 23:03

score 0 · Answer 2 · answered Feb 16 '14 at 14:25

0

You can find out the server information through its status page:

{running-tomcat-url}/manager/status

On that page you can see the version of Java on which your Tomcat runs

answered Feb 16 '14 at 14:25

Carlo Ledesma

406
1
3
7

Tomcat6 and JRE7 compatibility issue. Unsupported major.minor version 51.0

2 Answers2

Linked