Using a version range does not really solve the problem. What if you have:
foo-1.0: Export-Package: a;version="1.0" Import-Package: a;version="[1.0,2.0)" foo-1.1: Export-Package: a;version="1.1" Import-Package: a;version="[1.1,2.0)" The exact same problem will happen. On Fri, Jun 19, 2009 at 13:49, Felix Meschberger<[email protected]> wrote: > Hi, > > Guillaume Nodet schrieb: >> Let's say we have two bundles >> >> foo-1.0: >> Export-Package: a;version="1.0" >> Import-Package: a;version="1.0" >> >> foo-2.0: >> Export-Package: a;version="2.0" >> Import-Package: a;version="2.0" >> >> In felix (trunk), if you install foo-2.0, then foo-1.0, you end up with: >> >> foo-2.0: >> Export-Package: a;version="2.0" >> >> foo-1.0: >> Import-Package: a;version="2.0" > > This is correct as the resolution specification in Section 3.7, > Resolution of the core spec (right at the end of that section): > > The following list defines the preferences, if multiple choices are > possible, > in order of decreasing priority: > * A resolved exporter must be preferred over an unresolved exporter. > * An exporter with a higher version is preferred over an exporter with > a lower version. > * An exporter with a lower bundle ID is preferred over a bundle with a > higher ID. > > This, since foo-2.0 exports a more recent version, both should import > that version. > > To prvent foo-1.0 from importing a;version="2.0" the import would have > to be written as a version range excluding version 2.0: > > Import-Package: a;version="[1.0,2.0)" > > This would effectively result in foo-1.0 and foo-2.0 using incompatible > classes and not be able to exchange objects from the "a" package. > > (But you might want to have this ...) > > > There is catch, tough: Consider foo-1.0 installed and started. Now you > install and start foo-2.0. Now, foo-1.0 is wired to its own export and > foo-2.0 is wired to its own export and thus both bundles do *not* share > the a package.... If you then refresh foo-1.0 (with above import > declaration) it will wire to foo-2.0's export.... [You might call this a > corner case, but I am currently fighting such a case looking for a > solution]. > > > Regards > Felix > >> >> This really looks ackward (and will mostly lead to failures if the >> major versions are not really compatible), though I haven't seen >> anything in the core spec to forbid this. >> Section 3.7 says that the resolution for foo-1.0 should either choose >> an external package (which is what done here) or an internal package. >> >> Equinox seems to handle it using an internal package. >> >> What would you think about changing the resolution algorithm so that >> it try to use an internal package instead of an external package if >> all the constraints are met ? >> >> >> >> >> > -- Cheers, Guillaume Nodet ------------------------ Blog: http://gnodet.blogspot.com/ ------------------------ Open Source SOA http://fusesource.com
