Question

I was doing my homework in eclipse and it reported no errors, not even warnings. When I tried to compile it from terminal I got following error. It runs and compiles just fine with eclipse. I take it it has something to do with java version? Anyway to fix it or try to bypass it?

vedran@vedran-debian:~/java/oop/Aufgabe6$ java Test 
Exception in thread "main" java.lang.UnsupportedClassVersionError: Test : Unsupported major.minor version 51.0
    at java.lang.ClassLoader.defineClass1(Native Method)
    at java.lang.ClassLoader.defineClass(ClassLoader.java:634)
    at java.security.SecureClassLoader.defineClass(SecureClassLoader.java:142)
    at java.net.URLClassLoader.defineClass(URLClassLoader.java:277)
    at java.net.URLClassLoader.access$000(URLClassLoader.java:73)
    at java.net.URLClassLoader$1.run(URLClassLoader.java:212)
    at java.security.AccessController.doPrivileged(Native Method)
    at java.net.URLClassLoader.findClass(URLClassLoader.java:205)
    at java.lang.ClassLoader.loadClass(ClassLoader.java:321)
    at sun.misc.Launcher$AppClassLoader.loadClass(Launcher.java:294)
    at java.lang.ClassLoader.loadClass(ClassLoader.java:266)
Could not find the main class: Test. Program will exit.

Java version:

java version "1.6.0_23" 
OpenJDK Runtime Environment (IcedTea6 1.11pre) (6b23~pre11-1) 
OpenJDK 64-Bit Server VM (build 20.0-b11, mixed mode) 

EDIT:

Thank you all for your explanations. It seems to be a java6/7 issue. I just compiled it with 1.6 and it worked like charm.

Answer 1

The Test.class file has been compiled in Java 7 (major/minor version 51.0), so it’s incompatible with the Java 6 (major/minor version 50.0) runtime. Either compile the .java file in Java 6 (or earlier), or run the .class in a Java 7 runtime.