Modules merging support in ClassAnalyzer

[Mandy Chung]

Mark Reinhold wrote:
> I think it would be cleaner, and simpler, not to introduce a two-level
> naming scheme and a distinct concept of "group" module.  Instead just
> have modules with a single flat namespace and the ability to include one
> module into another.  The analyzer would only generate output files for
> "top level" modules, i.e., those that are not included in any other
> module.
>
> This would allow the fine-grained modules we've been using for analysis
> to be defined independently of the coarser-grained modules we'll use when
> we actually modularize the build.  Ideally such definitions could be kept
> in two separate files in order to allow easy experimentation.
>
> In concrete terms:
>
>   module jdbc-base
>   include java.sql.*
>
>   module jdbc-enterprise
>   include javax.sql.XA* javax.sql.rowset.**
>
>   module jdbc
>   include jdbc-base jdbc-enterprise
>
>   

My initial proposal was very close to what you suggest except that I 
used "require" instead of "include" for merging modules.   "require" may 
not be a good match and I didn't think of using "include" (that's a 
great suggestion).  In addition, Alan and I have an assumption that we 
only need to support two-level naming scheme and thus revised the proposal.

I agree that it's cleaner and simpler syntax that provides the ability 
to include one module into another instead of introducing a two-level 
naming scheme.
> This would generate just jdbc.{classlist,dependencies,summary}.
>
>   
>> Alan suggests to remove the "module" key and instead have the module name
>> quoted in a square bracket like this:
>>
>> [base]
>>
>> [jdbc:jdbc-base]
>> include = java.sql.*
>>
>> I don't have any objection to this syntax change.  I can make the change along
>> with the modules merging support.
>>     
>
> If we're going to change the syntax then I'd like to see it evolve toward
> something more like that of module-info.java files.  We'll gradually need
> to add more module-info-like constructs (e.g., permits), and in the long
> term I'd like the tool to be able to generate the module-info.java files
> which we'll need in the build.
>   

That's what we want the tool to do (generating the module-info.java file 
for the build to use).  I'll change the syntax after I add the module 
merging support.

Thanks
Mandy
> Something like this:
>
>   module jdbc-base {
>     include java.sql.*;
>   }
>
>   module jdbc-enterprise {
>     include java.sql.XA*, javax.sql.rowset.**;
>   }
>
>   module jdbc {
>     include jdbc-base, jdbc-enterprise;
>   }
>
> - Mark
>