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https://issues.apache.org/jira/browse/LUCENE-10255?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=17450624#comment-17450624
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Dawid Weiss commented on LUCENE-10255:
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Uwe... This was done with an announcement on the pull request and the issue. 
And it's also literally everywhere in the scripts you've reviewed ("-m 
lucene.luke"). 

If you really care so much about it and wish to change it to a full prefix we 
can still do it - 9.0 is not out yet.

> Fully embrace the java module system
> ------------------------------------
>
>                 Key: LUCENE-10255
>                 URL: https://issues.apache.org/jira/browse/LUCENE-10255
>             Project: Lucene - Core
>          Issue Type: New Feature
>            Reporter: Dawid Weiss
>            Priority: Major
>         Attachments: screenshot-1.png, screenshot-2.png
>
>          Time Spent: 3h 40m
>  Remaining Estimate: 0h
>
> I've experimented a bit trying to move the code to the JMS. It is 
> _surprisingly difficult_... A PoC that almost passes all checks is here:
> https://github.com/dweiss/lucene/tree/jms
> Here are my conclusions so far:
> * The JMS and gradle add a lot of complexity (this applies to any 
> higher-level tooling, including IDEs, I think). For starters, modules have to 
> be JARs. The effect of this is that what was previously a set of directories 
> from dependencies now has to be a JAR. What was previously an incremental 
> update of a single .class file now ripples throughout the build recreating 
> module JARs (ZIPs!)... I didn't realize it at first, but it's a costly thing 
> to do. I'm not even sure how IDEs handle this issue.
> * A Java module contains metadata (such as the module version or main class) 
> that is completely detached from any source file. These things live in a 
> class bytecode of the compiled module-info; interestingly, there is no 
> source-level way to specify it - these class attributes are injected by the 
> 'jar' tool. Gradle has some fancy on-the-fly asm conversion filter that 
> injects it.
> * Dependencies between modules will effectively live in two places: in gradle 
> build files and in module-info files. And they can go out of sync, although 
> it's probably easy to catch (since javac would complain about missing classes 
> during compilation, even if they're in module path).
> * Probably the biggest challenge (not covered in the PoC) are with our custom 
> javadoc and ecj linter tasks - they see the module-info.java and can't cope 
> with it. At the same time, there is no easy way to exclude that one 
> particular file: ecj would have to accept a full set of sources (command 
> argument limit will be a problem), javac can accept a full set of java 
> sources (external file) but then it doesn't copy doc-files properly anymore 
> (this is probably easier to fix). 
> * There are differences at runtime that are hard to anticipate - for example 
> resource lookups via class loader no longer work (I fixed this in Luke).
> After poking a bit and trying it out I have to say I have mixed feelings 
> about moving to the JMS. On the one hand, many things are great - the module 
> path, module descriptors and access modes. On the other hand, the tooling 
> tricks required to make it all work make you shiver.
> If anybody wants to play/ improve things on that experimental branch (I 
> converted Luke to a full module - it works), please be my guest. I have to 
> sit on this and think whether it's something I really like or not.



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