🚀 go-pugleaf

A partial solution to this problem appears in 

@InProceedings{ss94,
  author = 	 "Schwarz, Peter and Shoens, Kurt",
  title = 	 "Managing Change in the {Rufus} System",
  booktitle =	 "Proceedings of the IEEE International Conference on Data
		  Engineering",
  year =	 1994
}

Essentially a new release is considered a new version (in the database sense)
of the signatures of methods.  Object created under the old release continue
to access old versions of the code (unless the new version ``patches'' the
old version -- this is used only for bug fixes).  New objects access new
versions.  There are some other differences, since Rufus has an implicit
type hierarchy, but perhaps the idea can be adopted to Java. 
Unfortunately, the old release must be kept around until all objects
reference only the new release.
-- 
Anthony.Tomasic@inria.fr