Recently I faced this wired exception while running my Java application on Linux environment.
java.lang.UnsupportedClassVersionError: com.crunchify.testClass :
Unsupported major.minor version 51.0
at java.lang.ClassLoader.defineClass1(Native Method)
at java.lang.ClassLoader.defineClassCond(Unknown Source)
.........................................
The only difference I noticed in about Java Version. I compiled all code on my laptop with version 7 and Linux had version 6. java.lang.UnsupportedClassVersionError happens because of a higher JDK during compile time and lower JDK during runtime.
Now how to solve it?
- Project -> Properties -> Java Compiler
- Enable project specific settings.
- Then select Compiler Compliance Level to 1.6 or 1.5, build and test your app.
And that’s all.
J2SE 8=52, J2SE 7=51, J2SE 6.0=50, J2SE 5.0=49, JDK 1.4=48, JDK 1.3=47, JDK 1.2=46, JDK 1.1=45
The version numbers mentioned above are the version of the JRE the class file is compatible with. There is another way to fix this problem – try bundling your own required JVM with your application and set JAVA_HOME from your startup.sh script.
Thank you so much, the blog is helpful, my english is very poor so can’t express my gratitude.
You are welcome and thanks for your comment 🙂
Thnks my proble solved 🙂
I did already installed jdk 1.7 nd still I got error Unsupported major.minor version 51.0… anyone have idea about dis???
Hey Asutosh – you could verify if the class path is correctly set on you machine by below command:
Try executing above under Command Prompt or Terminal app if Mac.
clarifying post , good
Thanks. Keep visiting and happy coding.
hi, i did this and it didn’t work because for me, happened because I’d first added the build file to the ant-view when the default JRE was other. I found thes solution on this post:
http://stackoverflow.com/questions/949678/ant-is-using-wrong-java-version
Hi, how to do this in NetBeans IDE 8.0? Thanks.
Hey Oliver. I don’t use NetBeans. So sorry don’t know.
Another great post, App Shah! I’m loving this blog!
Thanks David.