ITECH 2100 6100 Assign 2 Java

This assignment requires you to do various tasks involving classes you write yourself and classes that you find in the SDK. The theme will be banks, customers and bank accounts. Note that this is a programming exercise only. It is designed to test your understanding of various aspects of Java programming. It is not intended to be a model of what happens in the real world – so don’t go changing things because “it makes more sense”.

You will be required to develop your application using Java in the Eclipse environment. You will need to zip the whole project up when you are finished and submit it on Moodle by the due date. You will also need to submit a report (both electronically in Moodle and as a hard copy). The report will require some written answers to questions which will be outlined in the various tasks. Please write clearly and IN YOUR OWN WORDS (plagiarism is NOT acceptable).

Task 1

Create a new project in Eclipse called Assignment 1.

Within this project create a package called task01.

1/ Download the class Date (you must use this class – not the ones in the SDK) from Moodle and add it to task01. This class has not been commented. You are required to add appropriate comments to this class.

In your report, answer the following:

• Provide a class diagram for this class.
• Look up the class Calendar in the Java API. What methods of the Calendar class are being used in the Date class?
• This will be a little research task. Write about half a page on “static fields and methods”. Include in your response answers to the following. What is their purpose? How do they differ from “instance methods”? How are static methods invoked? Which of Calendar’s fields are being accessed in the Date class? (Note – your answer to this MUST be written in your own words).

2/ Create a class called Address using the following class diagram as a guide. See image.

Your class should also include appropriate get and set methods. Furthermore, provide two constructors

• A default constructor which assigns each instance variable a default value. For example, you might assign the String “unknown street” to street.
• A constructor with three String parameters which assign values to each instance variable.

The method display ( ) should display this description. An example of an Address might be “12 Ballarat St” (street), “Bendigo” (city), “3353” (postcode), “Australia” (country). Thus the description might be

12 Ballarat St,
Bendigo, 3353
Australia

Ensure your class (and all classes that you author) are appropriately commented.

2/ Create a class called Person (class diagram below) See image.

The field, name, is the Person’s first name (eg “Fred”, “Sue”, “Rajiv” etc). We’ll only use first names for the sake of simplicity. The field, address, is the Person’s address (you’ve already created the Address class). The field, dob, is the Person’s date of birth. You must use the Date class you have downloaded from Moodle (not one supplied by the SDK).

Again include appropriate get and set methods. Furthermore include a default constructor and a constructor which will initialise the fields through parameters.

3/ Download the class Test01 from Moodle. This class contains the main method and some test code for the Address and Date classes. This testing is not exhaustive (it doesn’t test each of the methods in these classes). However, you can use the testDate and testAddress methods to give yourself an idea of whether you are on the right track with these classes (you will have to do some uncommenting in the main method).

The testPerson method has no code in it as yet. Provide code in this method that will exhaustively test the following methods of your Person class

• getDob
• setAddress
• toString

Task 2

Create a second package, called task02, within the project Assignment 1.

1/ Create a new class called SavingsAccount (class diagram follows) See image.

The field, accountNumber, is a unique identification number for each SavingsAccount object (eg “M1234”).

The field, balance, is the amount of savings in that particular account. The balance is set to zero when a SavingsAccount object is created. The balance is never allowed to go below zero. This object will require a getter and setter for accountNumber but not for balance. It should have a single constructor which sets the accountNumber. We won’t allow “unknown” account numbers. The balance will be set to zero in this constructor. The method, deposit, will add the value in the parameter to the balance. The method, withdraw, will succeed only if there are sufficient funds in the account. If there are, then balance is updated and true is returned , otherwise the balance remains unchanged and false is returned.

Supply an appropriate display ( ) methods.

2/ Create a new class called Customer that extends the Person from task01. Do not copy the class Person to the new package. Import it from the package. See image.

A Customer can have any number of accounts (including zero).

Customer requires the default constructor. It requires no get and set methods.

There are three methods to add, find and delete accounts. We will assume that addAccount always succeeds. However, the find and delete methods will fail if the account does not exist. Thus they will return true if the objects exist and false otherwise.

The method displayAllAccounts will loop through the Vector and display the details of each of the Customer’s accounts.

The method display ( ) will display all of the customer’s details (eg name, address etc) as well as the details of his/her accounts.

3/ Create a class called Bank (class diagram follows) See image.

Provide get and set methods for address and name. Provide at least two constructors. The Address class should be imported from task01 – it should not be copied into the task02 package. The discussion for the methods is very similar to that of the Customer class and won’t be repeated here.

4/ Download the Test02 class from Moodle. This class contains a test method for the Customer class. Provide exhaustive test code for both the SavingsAccount and Bank classes in the appropriate test methods. You will be marked on how thoughtful (careful) you are with your testing.

Task 3

Create a new package called Task03. Copy (don’t import this time – you’ll be making modifications to them) the classes Bank, SavingsAccount and Customer into this new package.

1/ Consider a class called CreditAccount with the following class diagram See image.

This is a second kind of account that a Customer can have. It differs from the SavingsAccount in that the Customer is allowed to have a creditLimit which means that his/her balance can be less than zero. If the creditLimit is $1000 then the customer can withdraw up to $1000 more than they have in their account. This will mean that the withdraw method will need to be implemented differently to SavingsAccount.

A Customer is allowed to have any number of accounts (either Savings or Credit). We can add these objects to the accounts Vector in the Customer class. However, we will find a lot of problems when we try to loop through them and perform operations them.

In your report, discuss an abstract class called Account which both SavingsAccount and CreditAccount will extend. Explain how such a class might be used to solve the problems outlined about. Discuss the

• Instance variables
• Concrete methods
• Abstract methods

which would belong to the Account class.

Finally, discuss the changes that you will need to make to the Customer and Bank classes to make the new arrangement work correctly.

2/ Implement the changes you have outlined in part 1. (Note you must use inheritance properties. Do not use any of the Reflection classes to solve these problems).

3/ Add an abstract method to Account called interest ( ). This method will need to be implemented differently in the subclasses.

• In SavingsAccount – add 1% to the balance.
• In CreditAccount – if the balance is positive add 2%. If negative charge 10% as interest.

In the Bank class add a method called updateInterest ( ) which will loop through each of the Customer objects in its customers Vector. For each customer, loop through all accounts and update the interest appropriately.

4/ Create a Test03 class with appropriate test methods. You will be marked upon how thoughtful (and careful) you are with your testing.