A Formal Semantics of UML Sequence Dia- grams

This paper presents a formal semantics of UML sequence diagram. In abstract syntax form, a well-formed sequence diagram corresponds to an ordered hierarchical tree structure. The static semantics of a sequence diagram is to check whether it is consistent with the class diagram declaration as well as with its well-formed tree structure. Meanwhile, the dynamic semantics is defined in terms of the state transitions that are carried out by the method invocations in the diagram. When a message is executed, it must be consistent with system state, i.e., object diagram and the state diagrams of its related objects. The semantics clearly captures the consistency between sequence diagram with class diagram and state diagram. Therefore, it is useful to develop the model consistent checking functions in UML CASE tools. And it also can be used to reason about the correctness of a design model with respect to a requirement model. This paper is to occur in the proceedings of ASWEC2004, 13-16 April, 2004, Melbourne, Australia. Xiaoshan Li is an Associate Professor at the University of Macau. His research areas are interval temporal logic, formal specification and simulation of computer systems, formal methods in system design and implementation. E-mail: [email protected]. Zhiming Liu is a Research Fellow at UNU/IIST, on leave from Department of Computer Science at the University of Leicester, Leicester, England where he is lecturer in computer science. His research interests include theory of computing systems, emphasising sound methods for specification, verification and refinement of fault-tolerant, real-time and concurrent systems, and formal techniques for OO development. His teaching interests are Communication and Concurrency, Concurrent and Distributed Programming, Internet Security, Software Engineering, Formal specification and Design of Computer Systems. E-mail: [email protected]. He Jifeng is a Senior Research Fellow of UNU/IIST. He is also a professor of computer science at East China Normal University and Shanghai Jiao Tong University. His research interests include the Mathematical theory of programming and refinement methods, design techniques for the mixed software and hardware systems. E-mail: [email protected]. Copyright c © 2004 by UNU-IIST, Xiaoshan Li, Zhiming Liu and He Jifeng