Comments on the module-file format

Jonathan Gibbons Jonathan.Gibbons at Sun.COM
Mon Feb 8 17:03:00 PST 2010


Mike Duigou wrote:
> Perhaps just a stylistic point but I don't really understand the predominance of unsigned types in the file format. Is this just a constraint expression that the values are never expected to be negative or is the extra bit worth of space really needed for any of the values? If it's for the extra range then perhaps the next larger natural size should be used instead. 
>
> For a Java standard it seems a little strange to use types which aren't natively supported and are either inconvenient or inefficient to use correctly.
>
> Or, maybe it's time to re-propose unsigned types for the JLS. ;-)
>
> Mike
>   
Mike,

I think the spec is just following the long-established precedent of the 
JVMS.  For example, see the spec for the class file format here: 
http://java.sun.com/docs/books/jvms/second_edition/html/ClassFile.doc.html

-- Jon



More information about the jigsaw-dev mailing list