Revert "added handleClassUpdate, handleClassDelete, and test cases"

This reverts commit 1cd992e70feb2ed1d1d91b3b8e669da707a1bd9d.
Revert "Revert "added handleClassUpdate, handleClassDelete, and test cases""

This reverts commit be84a345ddcaa0109c08f6fea66317d96b0ed8a8.