Exception in thread "main" java.lang.UnsupportedClassVersionError, Unsupported major.minor version 52.0
hadoop, java
Solution
Seems like you are using JDK8 for compiling and Lower version on Where you are using it.
So
Assuming using eclipse, `Window > Preferences > Compiler > compiler level`
and then set lower level(< current one ).
Problem
I am trying to run the WordCount example on hadoop - 1.0.4 and I am getting the following error: ``` Exception in thread "main" java.lang.UnsupportedClassVersionError: WordCount : Unsupported major.minor version 52.0 at java.lang.ClassLoader.defineClass1(Native Method) at java.lang.ClassLoader.defineClass(ClassLoader.java:791) at java.security.SecureClassLoader.defineClass(SecureClassLoader.java:142) at java.net.URLClassLoader.defineClass(URLClassLoader.java:449) at java.net.URLClassLoader.access$100(URLClassLoader.java:71) at java.net.URLClassLoader$1.run(URLClassLoader.java:361) at java.net.URLClassLoader$1.run(URLClassLoader.java:355) at java.security.AccessController.doPrivileged(Native Method) at java.net.URLClassLoader.findClass(URLClassLoader.java:354) at java.lang.ClassLoader.loadClass(ClassLoader.java:423) at java.lang.ClassLoader.loadClass(ClassLoader.java:356) at java.lang.Class.forName0(Native Method) at java.lang.Class.forName(Class.java:264) at org.apache.hadoop.util.RunJar.main(RunJar.java:149) ``` I use the following java version: ``` java version "1.7.0_11" Java(TM) SE Runtime Environment (build 1.7.0_11-b21) Java HotSpot(TM) Server VM (build 23.6-b04, mixed mode) ``` Also JAVA_HOME indicates to the java7 installation directory. Thanks for your help.