Re: [PATCH JGIT] Minor : Make ObjectId, RemoteConfig Serializable

> Nigel Magnay <nigel.magnay@gmail.com> wrote:
> > > A problem (big problem) with serialization is that it often leads to
> > > fragile interfaces. One might want to have precise control over
> > > the serialization so a change in the implementation doesn't affect
> > > compatibility. Serializing AnyObjectId should not depend on the
> > > implementation de jour. Second, how do we handle subclasses?
> > >
> > > But maybe leaving it this way would be our way of saying that
> > > the interface may break at any time, promise.
> > 
> > Well, we can of course implement writeObject / readObject (or do so
> > if/when compatibility breaks, and it's cared about)
> > 
> > That's how I tend to view it anyway (may break at any time) - you
> > can't just update a jar library to a significantly new version and
> > expect it all to stay compatible. Also for half my use, it's not for
> > persistence, it's for transferring over the wire to a slave process.

> > Thinking a bit more clearly, I probably don't need AnyObjectId, just
> > ObjectId - but I've also missed RefSpec and URIish as they're used in
> > RemoteConfig..
> 
> Here's my two cents... we can do this, but only if we implement
> Externalizable and do the read and write ourselves so we have a
> stable format.

> In the case of any of the types you are discussing there is an easy
> canonical form for them to be written on the wire, or to read back:
> 
>   ObjectId     - the 20 byte SHA-1
>   RefSpec      - the string form as it appears in the config file
>   URIish       - the string form as it appears in the config file