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Page 56 The verb phrase prints out the new account information is also an event initiated by the teller against the system. Therefore, you should incorporate it into your sequence diagram. Note Because the teller is specifying that account information be printed out, this suggests that print is a possible method for your Accountclass. This is true of each of your verbs and verb phrases; they become possible methods for the class indicated in the indirect object part of the sentence or phrase. Now you are ready to create your sequence diagram. Note that Samsona Bank Teller System will be represented by some class that implements one of its behaviors. Your lists of nominal nouns and verb phrases look like this: Nouns Customer Samsona Bank Teller System Checking history Telecheck Account (Property: Balance) Verbs Provide the customer information to the Samsona Bank Teller System Check the customer's checking history Provide the opening deposit balance to the Samsona Bank Teller System Print out the new account information Figure 2.7 shows your sequence diagram. You can use stick man figures, the Jacobson symbol for actors, for the teller and Telecheck. Although Telecheck is a machine-based system, you still model it as a stick man actor. The lines with the arrow at one end represent events and actions being carried out by actors and domain class instances (or objects). The rectangle preceding each line is called the focus of control bar. These bars indicate that each line protruding from it is part of the same event or action. For instance, the Teller-initiated event ProvideInfo is the only event in the teller's focus of control (or duration of a single event or action). However, both Check lines, as well as the SupplyHistory and Display History lines, are all part of the check history event initiated by the Teller. Rational Rose/Visual Basic enables you to do this type of modeling in an automated fashion.
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