Picocli already offers support for Graal integration with the ReflectionConfigGenerator, ResourceConfigGenerator, and DynamicProxyConfigGenerator tools in the picocli-codegen module.

This ticket is to improve that to allow picocli-based applications to generate Graal configuration files automatically during the build, and embed the generated files in the client jar so that no command line configuration is needed when creating a native image.

ReflectionConfigGeneratorProcessor

This is a subclass of the generic picocli annotation processor (#500).

It invokes the ReflectionConfigGenerator tool with the CommandSpec derived from the annotations at compile time.

By default it generates a config file in this location:

$CLASS_OUTPUT/META-INF/native-image/picocli-generated/reflect-config.json

This may be controlled by specifying processor options groupId and artifactId. For example, specifying "-AgroupId=example", "-AartifactId=full" will result in the file location to become:

$CLASS_OUTPUT/META-INF/native-image/example/full/picocli-generated/reflect-config.json

(JCommander users looking for Graal support: give this a try!)