How to use this to instrument a java application?

[PasinduTennage]

I am following this using the tutorial. It works fine for the given .js example.

I tried to use the same approach to instrument some java application, but it fails as follows.

class GFG {
  
    // Main driver method
    public static void main(String[] args)
    {
  
        // Print statement
        int a = 1+2;
    }
}

graalvm-ce-java11-21.2.0/bin/java --vm.Dtruffle.class.path.append=target/simpletool.jar --vm.Dtruffle.class.path.append=target/simpletool.jar --simple-code-coverage ../GFG

Output:

Unrecognized option: --jvm
Error: Could not create the Java Virtual Machine.
Error: A fatal exception has occurred. Program will exit.

I removed -jvm flag, and the corresponding output is:

Unrecognized option: --vm.Dtruffle.class.path.append=target/simpletool.jar
Error: Could not create the Java Virtual Machine.
Error: A fatal exception has occurred. Program will exit.

Can you give a java example?

Thanks

[boris-spas]

You can only use truffle instruments when you are running a truffle language - which running directly on the GraalVM JVM is not.

You should be able to use this instrument with "Java on truffle" (https://www.graalvm.org/reference-manual/java-on-truffle/). Instruction are in the link but in short - install espresso into your GraalVM and add -truffle to your java command line.

[saardev]

Hi, I'm trying the same thing you mentioned but it doesn't work. Is there anything else needed to enable the tool for Java on Truffle? Also running --version:graalvm doesn't seem to work at all in the Espresso standalone downloaded from https://www.graalvm.org/latest/reference-manual/java-on-truffle/ (and so I can't see the installed tools).