5. Objects and Classes (2)
Lab Exercise 5-2: Use Arrays to Represent Associations
In this exercise you will use arrays to implement the multiplicity on the
association between a bank and its customers.
To the banking package, you will add the Bank class as
modeled by the UML diagram above. A bank object simply keeps track of an association
between itself and its customers. We will implement this aggregate association
with an array of Customer objects. We will also need to keep a integer
attribute that keeps track of how many customers currently exist in the bank.
- Create the banking directory. Copy the previous Banking project
files in this package directory.
- Add two attributes to the Bank class: customers (an
array of Customer objects) and numberOfCustomers (an integer
that keeps track of the next customers array index).
- Add a public constructor that initializes the customers array
with some appropriate maximum size (at least bigger than 5).
- Add the addCustomer method. This method must construct a new
Customer object from the parameters (first name, last name) and
place it on the customers array. It must also increment the numberOfCustomers
- Add the getNumOfCustomers accessor method, which returns the
- Add the getCustomer method. This method returns the customer
associated with the given index parameter.
- Compile and run the TestBanking
program. You shoud see the following output:
Customer  is Simms, Jane
Customer  is Bryant, Owen
Customer  is Soley, Tim
Customer  is Soley, Maria