Do you need to add the class to module-info.java (similar to this)?

that makes sense, i forgot about the module-info.java file in this PR

working on it...

TL;DR: hit a snag, time-boxed myself to it, and i'm proposing not doing this in the interest of limiting changes here, and time-spent/ROI

but someone more knowledgeable can overrule me or advise here...

long version (as a person not well-acquainted with java modules):

• iiuc, to add module info i'll need to add a module info into reindex module too to put it into module path
• in order to feel comfortable doing so, i'll need to pay the ignorance tax and familiarize myself with java modules a bit more, given i'm not sure what adding a module-info to reindex will affect...
• i.e. can adding a module info into reindex be a breaking change in any way?
• my assumption is not, but i'd need to investigate further to assert that and be able to press merge with my name under it
• in the meantime, doesn't strike me as something blocking...

For the record: I agree that you should skip the module info.

If you have one, then you need to make sure you update it to include the SPI binding, because otherwise it won't find it. But if you don't have one (so your classes are going into the unnamed module), it works just fine with the META-INF/services alone.

And adding one here would mean adding one to all of its transitive dependencies, as you point out. And the last time we attempted that, we found that reindex depends on some REST client module whose name I forget (which it uses for reindex-from-remote) which is on Java 8 (presumably so users who are still on JDK 8 are able to use it — and, despite the fact that JDK 8 came out in 2014, it is under 'extended support' until 2030). And Java 8 doesn't have modules, resulting in some kind of compilation error (details of which I also forget). There's probably something smart we could do to work around this — maybe we use multi-release JARs or something? — but I don't think it's worth the considerable effort.