Towards Correct Object-Oriented Systems in Computational Logic

In our previous work, we have dened steadfastness, a notion of correctness that captures at once modularity, correctness and reusability. This paper attempts to extend it to Object-Oriented Systems, namely systems of cooperating objects, and is a rst step towards the introduction of correctness in Object-Oriented Design Frameworks. Such frameworks are increasingly recognised as more reusable than single objects, and promise to be useful components in next-generation Component-based Software Development

The UML as a Formal Modeling Notation

Abstract. The Uni ed Modeling Language (UML) is rapidly emerging as a de-facto standard for modelling OO systems. Given this role, it is imperative that the UML needs a well-de ned, fully explored semantics. Such semantics is required in order to ensure that UML concepts are precisely stated and de ned. In this paper we motivate an approach to formalizing UML in which formal speci cation techniques are used to gain insight into the semantics of UML notations and diagrams and describe a roadmap for this approach. The authors initiated the Precise UML (PUML) group in order to develop a precise semantic model for UML diagrams. The semantic model is to be used as the basis for a set of diagrammatical transformation rules, which enable formal deductions to be made about UML diagrams. A small example shows how these rules can be used to verify whether one class diagram is a valid deduction of another. Because these rules are presented at the diagrammatical level, it will be argued that UML can be successfully used as a formal modelling tool without the notational complexities that are commonly found in textual speci cation techniques.

Comparison of Formalisation Approaches of UML Class Constructs in Z and Object-Z

UML, and other object-oriented approaches to system specification and design, are increasingly popular in industry. Many attempts have been made to formalise either the notations, the system models produced using these notations, or both. However, there have been no attempts to compare the expressiveness of the formal approaches. This paper compares Z and Object-Z approaches to object-oriented formalisation

On Dynamic Aspects of OOD Frameworks in Component-based Software Development in Computational Logic

In component-based software development, object-oriented design (OOD) frameworks are increasingly recognised as better units of reuse than objects. This is because OOD frameworks are groups of interacting objects, and as such they can better reflect practical systems in which objects tend to have more than one role in more than one context. In an earlier paper, we described a formal semantics of the static aspects of OOD frameworks in computational logic. In this paper, we make a preliminary attempt to extend this to the dynamic aspects

Correct OO systems in computational logic

Object Oriented Design Frameworks (OOD frameworks) are groups of interacting objects. We have formalised them in computational logic as open systems of interacting objects. Our formalisation is based on steadfast logic programs in the context of open specification frameworks. However, we have considered only the static aspects, namely the specification of constraints and the correctness of queries (programs that do not update the current state). In this paper we extend this static model, by introducing actions that update the current state