[hibernate-dev] Copyright on hibernate XML interface?

[Serge Knystautas]

Oliver,

I would suggest you speak to an attorney on this or do more reading of 
copyright law.  Your gut is not far off, but you have some assumptions 
that are fundamentally misguided.

Interfaces are copyrightable just as much as an implementation is.  For 
example, UML is copyrighted.  Now UML is free because the copyright 
holders gave everyone a license to use it pretty openly [1], just as 
Hibernate is free because of the minimally restrictive license to use it 
[2].

I would also suggest going over the "fair use" concept for copyrights 
[3].  For example, your simple <composite-id> example would be allowed 
as fair use copy because it is such a small amount of the whole 
definition and isn't very unique.  However, if you used the whole HBM 
XML spec and just created a different implementation, that would have to 
be within Hibernate's license just as much as if you reimplemented 
org.hibernate.SessionFactory.

Anyway, IANAL so take all of this with a grain of salt, but i felt 
compelled to give you some words of caution and direction for further 
reading about this.

[1] see page 2 of the UML specifications 
http://www.omg.org/docs/formal/07-11-04.pdf
[2] http://www.hibernate.org/356.html
[3] http://en.wikipedia.org/wiki/Fair_use

-- 
Serge Knystautas
Lokitech >> software . strategy . design >> http://www.lokitech.com
p. 301.656.5501
e. sergek at lokitech.com

Oliver Plohmann wrote:
> Well, let's say you want to express that some primary key is a composite 
> of several keys. You will necessarily end up with something like this:
> 
> <composite-id>
>        <key-property name="fieldA"/>
>        <key-property name="fieldB"/>
> </composite-id>
> 
> This is partially imposed by the way XML works and to some point it is 
> simply common sense to create a solution in that way. And it is some 
> peace of valid hbm xml. Is it thefore protected by the hibernate 
> license, because it is part of the dtd? I believe not since this only 
> conveys that a composite consists of several parts. That's why I was 
> mentioning in my previous mail that there is no copyright on pure 
> definitions or interfaces. On the other hand, there are many things in 
> hbm xml that are very special in hibernate and not at all obvious or 
> common sense. I would guess that these parts would be considered worthy 
> of protection.
> 
> Anyway, it is starting to get annoying ... ;-). My conclusion I draw out 
> of this is that it would make sense to define some basic DSL using XML 
> to describe relationships between entities. This DSL would be free in 
> the same way that UML is free.
> 
> So long, Oliver