Hoss Man commented on SOLR-1656:
David: Interesting Idea. i must admit that while it feels very dirty, it's simplicity has some appeal.
I'm not positive, believe we could actually take this further by using ClassLoader.getResource() to generate a systemId for items pulled from the classpath as well (but i'm not sure if hte resulting URLs would be of any use to the DocumentBuilder if it doesn't also use the SolrResourceLoader)
Personally I think we should just bite the bullet and:
* implement a new SolrResourceLoader.openResourceAsInputSource(String)
* add the necessary constructors to start instantiating Config related options (SolrConfig, IndexSchema, etc) from InputSources
what appeals to me about your idea is that it wouldn't conflict with adding support for InputSource, and could work as a nice safety net for code that might use SolrResourceLoader to get an InputStream even if we had a new method for getting InputSources.
(the one key change i might suggest is to replace your InputStreamWithSystemId class with a one method marker interface "SystemIdable" and then use anonymous classes that implement that method -- it seems a little cleaner, and allows for the possibility of decorating other things with systemIds ... like Readers perhaps)