[stellation-res] Workspace rewrite status

[Dave Shields <shields@xxxxxxxxxxxxxx>]

I am in the midst of a major rewrite of the workspace code. Some
of it was done before we uncovered the recent repository problem
that Mark is sorting out now:

  Combine JavaChange and UnixChange into Change with system-dependent
  stuff moved to Files.

These changes passed our standard tests.

I also moved the archive management metohds needed for save/restore from 
Workspace to new class Archive.

The big change in progress is to implement a suggestion of Mark

      make Project an extension of BranchImage.

Until now, Project has maintained its own notion of the project directory
structure using Entry and Directory. But Project should, and will be, just
another kind of branch image, with added function to associate paths
with artifacts. Changes so far made include

  Drop Entry, EntryMap, Directory, DirectoryMap, ProjectCompoundManager.

  Make Project an extension of BranchImage, with appropriate method renaming
  in classes that use Project.

  Creation of artifacts by those that add to Project, rather than having
  Project create the artifacts.
 
  Changing methods in Project to use artifact identifiers for parameters
  and with 
     public Integer getID(String path)
     public String getPath(Integer ID)
  used to deal with path and ID assocation. The old Project often provided
  multiple ways to carry out the same action, and I am trying to trim this
  down to a sufficient minimal set of methods.

Most of the edits are done, and I just starting testing. I'll keep you
posted. I also welcome further changes consistent with the stated goals, with
other suggestions to be deferred until all this is sorted out.

I have also tried to reduce the number of instance variables, to make the
code simpler.

dave
-- 
Dave Shields, IBM Research, shields@xxxxxxxxxxxxxx.