Check JDK Version used to compile a class

If you want to check the JDK version used to compile a class, use the below command

javap -verbose MyClass

Where MyClass is the class file you are checking.


Some example values it will return are

• Java 1.2 uses major version 46
• Java 1.3 uses major version 47
• Java 1.4 uses major version 48
• Java 5 uses major version 49
• Java 6 uses major version 50