Unifying classes and processes

Previously, we presented Circus, an integration of Z, CSP, and Morgan’s refinement calculus, with a semantics based on the unifying theories of programming. Circus provides a basis for development of state-rich concurrent systems; it has a formal semantics, a refinement theory, and a development strategy. The design of Circus is our solution to combining data and behavioural specifications. Here, we further explore this issue in the context of object-oriented features. Concretely, we present an object-oriented extension of Circus called OhCircus. We present its syntax, describe its semantics, explain the formalisation of method calls, and discuss our approach to refinement.