java.lang.UnsupportedClassVersionError

Hi,
       when I was running the the servelt class in  apache tomcat 6, I was getting below error:

SEVERE: Error deploying web application directory examples
java.lang.UnsupportedClassVersionError: firstServlet : Unsupported major.minor version 51.0 (unable to load class firstServlet)

SEVERE: End event threw exception
java.lang.reflect.InvocationTargetException
    at sun.reflect.GeneratedMethodAccessor33.invoke(Unknown Source)

The root cuase for this i found that:

  I compiled the Java code with upper compiler (1.7) version and was trying to run it with lower version(1.5) of JVM.

Fix:
    compiled the java code with 1.5 and ran with the same..Now working fine

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