Class has been compiled by a more recent version of the Java Environment

If you get the error "class has been compiled by a more recent version of the Java Environment", it means that you are trying to run a class file that was compiled with a newer version of Java than the one you have installed.

For example, if you have Java 8 installed and you try to run a class file that was compiled with Java 11, you will get this error. This is because the class file contains bytecode that is not compatible with the older version of the Java runtime.

To fix this error, you need to install the newer version of Java that was used to compile the class file and then run the class file with that version.

Alternatively, you can try to recompile the class file with the older version of Java that you have installed. You can do this by specifying the --release option with the javac compiler, for example:

javac --release 8 MyClass.java

This will compile the MyClass.java file with the language features and APIs available in Java 8, so it can be run with that version of the Java runtime.

Keep in mind that this will only work if the class file does not use any language features or APIs that are not available in the older version of Java. If the class file uses features that are not present in the older version, you will get a compilation error.