This contribution discusses system modeling with UML behavior diagrams. We consider statecharts and both kinds of interaction diagrams, i.e., sequence and communication diagrams. We present new implementation features in a UML and OCL modeling tool: (1) Sequence diagram lifelines are extended with states from statecharts, and (2) communication diagrams are introduced as an alternative to sequence diagrams. We assess the introduced features and propose a systematic set of features which should

more »

... available in both kinds of interaction diagrams. We emphasize the role that OCL can play for such a feature set. Permission to make digital or hard copies of all or part of this work for personal or classroom use is granted without fee provided that copies are not made or distributed for profit or commercial advantage and that copies bear this notice and the full citation on the first page. Copyrights for components of this work owned by others than the author(s) must be honored. Abstracting with credit is permitted. To copy otherwise, or republish, to post on servers or to redistribute to lists, requires prior specific permission and/or a fee. Request permissions from Permissions@acm.org. and postconditions for constraining behavioral ones, among other uses of OCL [15; 17] within UML. This contribution focuses on UML interaction diagrams in form of sequence and communication diagrams. We introduce new features for interactions in a UML tool and discuss how the two interaction diagrams could be handled in uniform way. Since about 15 years our group is developing the UML and OCL tool USE (UML-based Specification Environment). USE [5; 6] originally started as a kind of OCL interpreter with class, object and sequence diagrams available in the tool from the beginning. Other behavioral diagrams have been added over the last years, namely statechart diagrams in form of protocol state machines and most recently communication diagrams. USE claims to be useful for validation and verification of UML and OCL models. The structure of the rest of this paper is as follows. Section 2 introduces a running example. Section 3 shows the UML metamodel for interactions and sets the context for the interaction diagram implementation within USE. Section 4 presents new features in sequence diagrams, and Sect. 5 discusses communication diagrams. Section 6 proposes a systematic set of features that could be available in both interaction diagrams. Section 7 compares our approach to related papers. The contribution is closed in Sect. 8 with concluding remarks and future work.