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https://issues.apache.org/jira/browse/LUCENE-9281?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=17061670#comment-17061670
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Uwe Schindler commented on LUCENE-9281:
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I opened a Github Pull Request using my idea. I did not yet implement it for 
all Factory subclasses (this will be a quite huge patch), so this is for a 
quick review only, to discuss ideas: 
https://github.com/apache/lucene-solr/pull/1360

> Retire SPIClassIterator from master because Java 9+ uses different mechanism 
> to load services when module system is used
> ------------------------------------------------------------------------------------------------------------------------
>
>                 Key: LUCENE-9281
>                 URL: https://issues.apache.org/jira/browse/LUCENE-9281
>             Project: Lucene - Core
>          Issue Type: Improvement
>          Components: core/other
>    Affects Versions: master (9.0)
>            Reporter: Uwe Schindler
>            Assignee: Uwe Schindler
>            Priority: Major
>             Fix For: master (9.0)
>
>          Time Spent: 10m
>  Remaining Estimate: 0h
>
> We currently have our own implementation of the service loader standard (SPI) 
> fo several reasons:
> (1) In some older JDKs the order of classpath was not respected and this lead 
> to wrong order of codecs implementing the same SPI name. This caused tests to 
> sometimes use wrong class (we had this in Lucene 4 where we had a test-only 
> read/write Lucene3 codec that was listed before the read-only one). That's no 
> longer an issue, the order of loading does not matter. In addition, Java now 
> does everything correct.
> (2) In Analysis, we require SPI classes to have a constructor taking args (a 
> Map of params in our case). We also extract the NAME from a static field. 
> Standard service loader does not support this, it tries to instantiate the 
> class with default ctor.
> With Java 9+, the ServiceLoader now has a stream() method that allows to 
> filter and preprocess classes: 
> https://docs.oracle.com/en/java/javase/11/docs/api/java.base/java/util/ServiceLoader.html#stream()
> This allows us to use the new interface and just get the loaded class (which 
> may come from module-info.class or a conventional SPI file): 
> https://docs.oracle.com/en/java/javase/11/docs/api/java.base/java/util/ServiceLoader.Provider.html#type()
> This change allows us to convert Lucene to modules listing all SPIs in the 
> module-info.java.



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