Controlling Concurrent Accesses in an Object-Oriented Environment

The purpose of this paper is to propose a way of controlling concurrent accesses in an objectoriented environment. The object-oriented approach places specific constraints on data model and on accesses, which we discuss. We then propose a lock-based protocol. Its qualities are: an unlimited range of access modes and the automatic creation of the corresponding locks; the possibility of hierarchical accesses; the ability to deal with the well-known problem of “phantom objects”, and the similar problem of modifying the inheritance graph.