I was not aware that cross visibility quirkiness remained even on published artifacts, so I’ve found these to be some rules of thumb I wasn’t aware:

1. Transient dependencies are not accessible. (as opposed to what some
   sources have said) I was told that if B implements A, I would have
   access to A from C when C implements B… this was not the case
   after testing. (Because of #1, I was structuring the artifacts
   dividing them in submodules, classifying them based on degree of
   outer dependance.)

2. Artifact submodules can ONLY be accessed directly under main/java.
   If a class’ path goes deeper than this, the class will have access
   to none of the submodule’s contents:

On build.gradle:

dependencies {
    implementation('io.github.org:anartifact-submodule:1.0.0')
}

From src/main/java/some_package/DeepClass.java

package some_package;

import io.github.org.anartifact_submodule.SomeClass;
// import anartifact_submodule.SomeClass;
// import submodule.SomeClass;

public class DeepClass {
   SomeClass sc = new SomeClass();
}

“cannot resolve [ io | anartifact_submodule | submodule | SomeClass ] symbol”

Now from main/java/SurfaceClass.java:

class SurfaceClass {
   SomeClass sc = new SomeClass();
}

No issue, no import needed.

How can I access a submodule’s content from inside a package?