Graal: Extending native applications with Java and JS

[guaporocco]

Hello,

I'd like to use Graal to extend a c++ application to support polyglot execution of Java and JS (ie, extending a native application).

However, it does not seem possible to use Java as a "guest-language." Would my best bet be to implement Java in truffle? Or is the Graal JVM compiler already using such an AST?

Alternatively, I suppose I could use JNI to embed GraalVM in JVM mode. Then I'd use the ToolProvider api to javac a passed .java URI, and then execute. One would lose the security benefit of running in Isolates however.

[mukel]

We are already working on a Truffle bytecode interpreter for GraalVM. Still an early prototype but it's already able to run javac and compile itself.
Fully dynamic Java code e.g. user provided; it's not supported by SVM.

[guaporocco]

Awesome! Looking forward to seeing truffleJava. Since substrate VM doesn't support dynamic loading, I'll just use JNI then (or maybe even a Panama project early access 😉 )

[mukel]

We generally want to avoid the name TruffleJava because it implies that the Java we are running is somehow different.
The project name is Espresso and is just "Java on GraalVM".