Step: Distribute behavior to analysis classes

For each independent sub-flow (scenario):

• Create one or more collaboration diagrams.  At least one diagram is usually needed for the main flow of events of the use case, plus at least one diagram for each alternate/exceptional flow.  Separate diagrams are usually needed for sub-flows which have complex timing or decision points, or to simplify complex flows which are too long to grasp easily in one diagram.
• Identify the analysis classes responsible for the required behavior by stepping through the flow of events of the scenario, ensuring that all behavior required by the use case is provided by the use-case realization.
• Illustrate  interactions between  analysis classes in the collaboration diagram. The collaboration diagram should also show interactions of the system with its actors (the collaborations should begin with an actor, since an actor always invokes the use case).
• Include classes that represent the control classes of used use-cases. (Use a separate collaboration diagram for each extending use-case, showing only the variant behavior of the extending use case.)

A collaboration diagram for the use case Receive Deposit Item.