Chapter 9. Modeling Message-Based Behavior with Interactions
This chapter discusses the use of sequence diagrams to model how parts of a block interact by exchanging messages.
In Chapter 8, behavior was modeled in terms of activity diagrams to represent a controlled sequence of actions that transform inputs to outputs. In this chapter, an alternative approach to representing behavior is introduced; it uses sequence diagrams to represent the interaction between structural elements of a block as a sequence of message exchanges. The interaction can be between the system and its environment or between the components of a system at any level of a system hierarchy. A message can represent the invocation of a service on a system component or the ...