layrry VS moditect

No, JPMS does not automatically turn the JVM into an NPM like experience with the same dependency being available in different versions. It is possible using the layer feature JPMS introduced, for example with Layrry, but as I understand it, by default Java only has 2 (?) layers, bootstrap and application, corresponding to the bootstrap and application classloaders.

Use https://github.com/moditect/layrry which is based on Java Modules. Not tried yet. Sbt does not recognize module-info.java which is essential for it to work. Possible solution is implement an Sbt Plugin. But, I don't know if at the end this would work in development mode which is important.

github.com/moditect/layrry

And then you have to use moditect to generate a module-info.java and this is again because the annotation processor will pick up the provides Processor with YourAnnotationProcessor.

Maybe you've somehow missed https://maven.apache.org/plugins/maven-jlink-plugin/ https://github.com/moditect/moditect https://github.com/beryx/badass-jlink-plugin https://github.com/sormuras/testing-in-the-modular-world

Yes, you are right. jlink does not work with automatic modules. But using that plugin https://github.com/moditect/moditect you can easily transform almost any java library into a named module. It is a shame there are libraries under development, that have not been adapted to the java modular system.

FWIW, I've had a lot more issues with reflective access when using GraalVM. Reflection is mainly a problem with modules if you forget to 'open' your modules which is easy to fix in many cases. There's also moditect if the library author still doesn't want to learn how to include a module-info in the legacy compatible jar.

Thanks. I don't think iText has a modularized jar. Would it be possible to inject the modules into my jar, as per: https://stackoverflow.com/questions/47222226/how-to-inject-module-declaration-into-jar . Or maybe use moditect?

Or apply the https://github.com/moditect/moditect plugin and keep the build in JDK8. Let the plugin create the module descriptors without configuring JDK toolchains.

You can use the https://github.com/moditect/moditect maven plugin to add the module-info to the third-party jars

The next solution, which is the one I'm writing about. Is to modularize foo's jar, this is easily accomplished using the moditect plugin. But it can be tricky since I don't have, nor do I need, bar, and I prefer doing most of the work in build time and not manually.

It's possible to add this information during one's build even though the procedure is error-prone and boring. The description on how to achieve this deserves a post on its own. For more information, please check this Oracle magazine article. Suffice to say here that it makes heavy use of the Moditect Maven plugin.