Object-Oriented Design - Java Concepts - page 793

΢΢ Exercise R12.5. After discovering a method, why is it important to
identify the object that is responsible for carrying out the action?

΢ Exercise R12.6. What relationship is appropriate between the following

classes: aggregation, inheritance, or neither?

a. UniversityÎStudent

b. StudentÎTeachingAssistant

c. StudentÎFreshman

d. StudentÎProfessor

e. CarÎDoor

f. TruckÎVehicle

g. TrafficÎTrafficSign

h. TrafficSignÎColor

΢΢ Exercise R12.7. Every BMW is a vehicle. Should a class BMW inherit from
the class Vehicle ? BMW is a vehicle manufacturer. Does that mean that
the class BMW should inherit from the class VehicleManufacturer ?

΢΢ Exercise R12.8. Some topics on object-oriented programming recommend
using inheritance so that the class Circle extends the class Point . Then
the Circle class inherits th e setLocation method from the Point
superclass. Explain why the setLocation method need not be redefined
in the subclass. Why is it nevertheless not a good idea to have Circle
inherit from Point ? Conversely, would inheriting Point from Circle
fulfill the is-a rule? Would it be a good idea?

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΢ Exercise R12.9. Write CRC cards for the Coin and CashRegister

classes described in Section 8.2 .

΢ Exercise R12.10. Write CRC cards for the Bank and BankAccount

classes in Section 7.2 .