Revisiting statechart synthesis with an algebraic approach

Abstract

The idea of synthesizing statecharts out of a collection of scenarios has received a lot of attention in recent years. However due to the poor expressive power of rst generation scenario languages, including UML1.x sequence diagrams, the proposed solutions often use ad hoc tricks and su er from many shortcomings. The recent adoption in UML2.0 of a richer scenario language, including interesting composition operators, now makes it possible to revisit the problem of statechart synthesis with a radically new approach. Inspired by the way UML2.0 sequence diagrams can be algebraically composed, we rst de ne an algebraic framework for composing statecharts. Then we show how to leverage the algebraic structure of UML2.0 sequence diagrams to get a direct algorithm for synthesizing a composition of statecharts out of them. The synthesized statecharts exhibit interesting properties that make them particularly useful as a basis for the detailed design process. Beyond o ering a systematic and semantically well founded method, another interest of our approach lies in its exibility: the modi cation or replacement of a g i v e n s c enario has a limited i m p act on the synthesis process, thus fostering a better traceability between the requirements and the detailed design. 1 1 This work has been partially supported by t h e F AMILIES European project. Eureka P ! 2023 Program, ITEA project ip 02009.

From UML 2 Sequence Diagrams to State Machines by Graph Transformation.

“…Our methodology is quite similar to the one prescribed by Whittle and Schumann [WS00] and Ziadi et al [ZHJ04]. Whittle and Schumann need OCL expressions to express similar behavior across multiple diagrams, while we and Ziadi et al take advantage of the combined fragments which were introduced in UML 2 after the work of Whittle and Schumann.…”

“…Ziadi et al [ZHJ04] define their transformation by pseudocode operating on algebraic definitions of sequence diagrams and state machines, while our transformation is based on graph transformation. Our support for guards in alt/loop and support for par/opt/neg is new compared to their approach.…”

“…[KGSB99,WS00,ZHJ04,Sun07]). None of the previous approaches takes full advantage of the combined fragments that were introduced in UML 2.…”

Synthesis and Refinement Check of Sequence Diagrams

“…Other approaches to model asynchrony of a sequence diagram are also presented [16], [17], [26], [27]. Krüger et al [26] proposed the method to generate statecharts from a set of Message Sequence Charts [28].…”

“…Krüger et al [26] proposed the method to generate statecharts from a set of Message Sequence Charts [28]. Ziadi et al [27] proposed to generate statecharts from sequence diagrams and defined algebraic framework for composing statecharts. These methods represent asynchrony of sequence diagrams clearly by the parallel composition of statecharts.…”