Exception in thread “main” java.lang.UnsupportedClassVersionError: com/crunchify/Main : Unsupported

https://crunchify.com/exception-in-thread-main-java-lang-unsupportedclassversionerror-comcrunchifymain-unsupported-major-minor-version-51-0/

完美解决！！！！

Recently I faced this wired exception while running my Java application on Linux environment.

Javaa Error Message

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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?

1. Project -> Properties -> Java Compiler
2. Enable project specific settings.
3. Then select Compiler Compliance Level to 1.6 or 1.5, build and test your app.

And that’s all.

Java Version and Versions

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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.shscript.

Would love to know what you think. Chime in and share it as a comment. Don’t forget to share this guide!