Java run error

Hello,

I created a simple hello world java file, i compiled it, and it worked, and when i tried to run it, i got the following error:

Error: A JNI error has occurred, please check your installation and try again
Exception in thread "main" java.lang.UnsupportedClassVersionError: ClassA has been compiled by a more recent version of the Java Runtime (class file version 57.0), this version of the Java Runtime only recognizes class file versions up to 52.0
       at java.lang.ClassLoader.defineClass1(Native Method)
       at java.lang.ClassLoader.defineClass(Unknown Source)
       at java.security.SecureClassLoader.defineClass(Unknown Source)
       at java.net.URLClassLoader.defineClass(Unknown Source)
       at java.net.URLClassLoader.access$100(Unknown Source)
       at java.net.URLClassLoader$1.run(Unknown Source)
       at java.net.URLClassLoader$1.run(Unknown Source)
       at java.security.AccessController.doPrivileged(Native Method)
       at java.net.URLClassLoader.findClass(Unknown Source)
       at java.lang.ClassLoader.loadClass(Unknown Source)
       at sun.misc.Launcher$AppClassLoader.loadClass(Unknown Source)
       at java.lang.ClassLoader.loadClass(Unknown Source)
       at sun.launcher.LauncherHelper.checkAndLoadMain(Unknown Source)

"It doesn't work" is useless. How would we even begin without seeing your code?

Welcome to the Ranch

The stack trace you posted gives you some useful information: look at its first line. Subtract 44 from the version numbers shown and you find your code has been compiled with Java13 (57−44) but you are trying to run it with a Java8 (52−44) runtime. You can run older bytecode on a newer JVM but not vice versa. The problem might be caused by your setting your PATH wrongly. Please try the following instructions at a command line/terminal:-Windows only:- java -version javac -version echo %PATH%Linux/Unix/Mac OS/X:- java -version javac -version echo $PATHPlease show us what the results of those instructions are.

Can you go to a command prompt and type

   java -version

then type

   javac -version

then post the output of those two commands?

Hi, thanks for answering.
I am in deed using different versions, but I have no idea how to correct that.
here is the output of the command line instructions:

java -version
java version "1.8.0_241"
Java(TM) SE Runtime Environment (build 1.8.0_241-b07)
Java HotSpot(TM) Client VM (build 25.241-b07, mixed mode, sharing)

>javac -version
javac 13.0.2

echo %PATH%
C:\Program Files (x86)\Common Files\Oracle\Java\javapath;C:\Windows\system32;C:\Windows;C:\Windows\System32\Wbem;C:\Windows\System32\WindowsPowerShell\v1.0\;C:\Windows\System32\OpenSSH\;C:\Program Files\Git\cmd;C:\Users\Nour\AppData\Local\Microsoft\WindowsApps;C:\Program Files\JetBrains\IntelliJ IDEA Community Edition 2019.3.3\bin;C:\Program Files\Java\jdk-13.0.2\bin

The approach I use is this:

First I set up a new environment variable: JAVA_HOME
Set to: C:\Program Files\Java\jdk-13.0.2

Then modify the PATH, replacing the Oracle path in the beginning, and removing the jdk path at the end.

%JAVA_HOME%\bin;C:\Windows\system32;C:\Windows;C:\Windows\System32\Wbem;C:\Windows\System32\WindowsPowerShell\v1.0\;C:\Windows\System32\OpenSSH\;C:\Program Files\Git\cmd;C:\Users\Nour\AppData\Local\Microsoft\WindowsApps;C:\Program Files\JetBrains\IntelliJ IDEA Community Edition 2019.3.3\bin

Most people seem to like this approach but some do not. YMMV.

Edit: I don't use IntelliJ so I have no idea if this approach is compatible.

As long as you have the PATH entry to Java13 at the start of the PATH, as Carey said, you will be all right. You will have to edit the JAVA_HOME variable whenever you update your Java® installation. You might need a new command line or even a reboot before the new PATH comes into operation.
You can also set the PATH like this (not sure of correct format)Command line:- set PATH="C:\Program Files\Java\jdk8u241\bin";%PATH%The above might be incorrect. Not sure. I hardly ever use Windows®.

I wouldn't do that.  I think the OP's PATH is more complex than that.  I would do the editing of the PATH in the GUI Windows provides and it looks like the OP already knows how to do that.