To give some context, this signature is used for the purpose of deciding if a class's API has changed... *as far as other Java source files are concerned for the purposes of running javac*. It has no effect on TypeOracle or the data presented there, it's not being used to cache old TypeOracle models.
Using sort order means a user can sort a file without changing its API and not have to recompile the dependent files. -- http://groups.google.com/group/Google-Web-Toolkit-Contributors
