Updated UML Class Diagram for Class GradeBook

The UML class diagram of Fig. 3.4 models class GradeBook of Fig. 3.3. Like the class GradeBook defined in Fig. 3.1, this GradeBook class contains public member function displayMessage. However, this version of displayMessage has a parameter. The UML models a parameter by listing the parameter name, followed by a colon and the parameter type in the parentheses following the operation name. The UML has its own data types similar to those of C++. The UML is language independent—it’s used with many different programming languages—so its terminology does not exactly match that of C++. For example, the UML type String corresponds to the C++ type string. Member function displayMessage of class GradeBook (Fig. 3.3, lines 13–17) has a string parameter named courseName, so Fig. 3.4 lists courseName : String between the parentheses following the operation name displayMessage. This version of the GradeBook class still does not have any data members.

Fig. 3.4. UML class diagram indicating that class GradeBook has a public displayMessage operation with a courseName parameter of UML type String.