Supporting Change Management of Sequence Diagrams

UML Sequence diagram is an effective model to specify behaviors of the target system. Sequence diagrams can be used for specifying interactions between a system and its user, and interactions between objects. Just like scenarios, sequence diagrams are useful for requirements elicitation in the requirements definition. Sometimes sequence diagrams should be modified in accordance with requirements changes or correction of errors. In such a modification, careless mistakes may lead to include another error in the diagram. As a result, careless modifications may lead to a failure of software development. In this paper, we propose a method of visualization of the difference between original sequence diagram and modified one by emphasizing the difference in order to eliminate newly produced errors in the modified sequence diagram. We adopt PlantUML as a description language and a viewer of sequence diagrams. We illustrate our method using a prototype system written with Java with an example.