java - Unsupported major.minor version 52.0 - edu/stanford/nlp/classify/ColumnDataClassifier

I am using stanford-classifier-3.5.1 jar on my system and trying to run the example classifier only. I am getting the following error:

Exception in thread "main" java.lang.UnsupportedClassVersionError: edu/stanford/nlp/classify/ColumnDataClassifier : Unsupported major.minor version 52.0
    at java.lang.ClassLoader.defineClass1(Native Method)
    at java.lang.ClassLoader.defineClass(ClassLoader.java:800)
    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$1.run(URLClassLoader.java:355)
    at java.security.AccessController.doPrivileged(Native Method)
    at java.net.URLClassLoader.findClass(URLClassLoader.java:354)
    at java.lang.ClassLoader.loadClass(ClassLoader.java:425)
    at sun.misc.Launcher$AppClassLoader.loadClass(Launcher.java:308)
    at java.lang.ClassLoader.loadClass(ClassLoader.java:358)
    at ClassifierDemoStanford.main(ClassifierDemoStanford.java:20)

I have tried with Java version 1.6, 1.7 both. The readme file says This software requires Java 5 (JDK 1.6.0+).
Please help.

Answer

The error message means that the code requires Java 8. I checked out the website and the latest release supports Java 8, since October 2014.

I would estimate that the readme file is out of date.

If you use Java 8 it will run this fine.

If you can't upgrade to Java 8, you might downgrade the version of the classifier jar file to the version before Java 8 was added - version 3.4.1

http://nlp.stanford.edu/software/classifier.shtml