Description
For this assignment, you will be writing four classes, including Account, CheckingAccount,
SavingsAccount, and AccountTest class.
The Account class represents a bank account. An account can be used for deposit, withdraw, and
transfer. Each account has two variables, acctNo and balance. Use String type for acctNo and
double type for balance. The variables should be private.
CheckingAccount and SavingsAccount are subclasses of Account. CheckingAccount has an
additional variable that represents the overdraft amount. It also has a static variable that represent
the overdraft fee. SavingsAccount has an additional variable that represents the interest rate.
AccountTest class is the class with the main method. It tests all the methods (including
constructors) of the three other classes.
1. Account class
You will need to write the following methods for the Account class:
Constructors
All constructors should be defined as “public”.
• A one-parameter constructor should be included. The parameter is a given account
number (of String type). The default balance is zero.
• A two-parameter constructor should be included. The two parameters are a given account
number and an initial balance. The initial balance should be non-negative.
Public Methods
• getAcctNo – This is a “get” method used to get the account number.
• getBalance – This is a “get” method used to get the account balance.
• setBalance – This is a “set” method used to set the account balance.
Since the account number should not be modified manually, so there should be no set
method for acctNo.
• deposit – This method should receive a double value as a parameter. The parameter
indicates the amount to be deposited into the account. The amount should be positive
(otherwise it doesn’t do anything and the program should print a message). The account
balance should be updated accordingly.
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• withdraw – This method should receive a double value as parameter. The parameter
indicates the amount to be withdrawn to the account and the balance should be decreased
accordingly. The withdrawal amount should be positive (otherwise it doesn’t do anything
and the program should print a message). If there is not enough money in the account to
be withdrawn, a message should be printed and no withdrawal is done.
• transfer – This method allows transferring money from this account to another account.
There are two parameters, an object of Account and the amount to be transferred to. The
amount should be positive (otherwise it doesn’t do anything and the program should print
a message). The balance of both accounts should be updated accordingly. If there is not
enough money in this account, a message should be printed and no transfer is done. For
example, to transfer $100 from account a1 to a2, it should call
a1.transfer(a2, 100.0)
• displayInfo – this method takes no parameter. It displays the account information in the
following format:
Account number:
Current balance:
Overridden Methods
The following method is inherited from the Object class, and you will need to overwrite it.
• toString – This method takes no parameter and returns a String object. It returns a String
object with the account information in the following format:
Account number:
Current balance:
• equals – This method has one parameter of Object type and returns a boolean value. If
the object that is passed as a parameter is not any type of account, it should return
false. Two accounts are equal if they have the same acctNo.
2. CheckingAccount class
CheckingAccount is a subclass of Account class. It has a new variable called overdraft (using
double type) that represents the overdraft amount (such as -200.0). A checking account can have
negative balance as long as it is not lower than overdraft amount. But every time an overdraft is
done, there is a fixed fee. Use a static variable called fee to represent the fee. This overdraft fee
is the same for all the checking accounts, so it should be static.
Constructors
All constructors should be defined as “public”. Keep in mind that a subclass’s constructor should
first call a constructor in the super class.
• A one-parameter constructor should be included. The parameter is a given account
number. The default balance and overdraft amount are zero.
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• A three-parameter constructor should be included. The three parameters are a given
account number, an initial balance, and a given overdraft amount. The initial balance
should be non-negative.
Public Methods
• getOverdraft – This is a “get” method used to get the overdraft amount.
• setOverdraft – This is a “set” method used to modify the overdraft amount.
• getFee – This is a “get” method used to get the overdraft fee.
• setFee – This is a “set” method used to modify the overdraft fee.
Overridden Methods
The following methods are inherited either from the Object class or the Account class, and you
will need to overwrite them.
• toString – This method takes no parameters and returns a String object. It returns a
String object in the format of:
Account number:
Current balance:
Overdraft amount:
• withdraw – This method is similar to the withdraw method in Account class except that
even if there is not enough money in the checking account, a withdraw can be done as
long as it is within overdraft limit, but overdraft fee will be charged. The new balance
after the fee charge cannot be lower than the overdraft limit.
• transfer – This method is similar to the transfer method in Account class except that
even if there is not enough money in the checking account, a transfer can be done as long
as it is within overdraft limit, but overdraft fee will be charged. The new balance after the
fee charge cannot be lower than the overdraft limit.
• displayInfo – this method takes no parameter. It prints the checking account information
in the following format:
Account number:
Current balance:
Overdraft amount:
3. SavingsAccount class
This class is also a subclass of Account class. It has a new variable called interestRate (using
double type) that records the interest rate (such as 0.03). Saving accounts do not allow overdraft,
i.e., the balance cannot be negative.
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Constructors
All constructors should be defined as “public”. Keep in mind that a subclass’s constructor should
first call a constructor in the super class.
• A one-parameter constructor should be included. The parameter is a given account
number. The default balance and interest rate are zero.
• A three-parameter constructor should be included. The three parameters are a given
account number, an initial balance, and a given interest rate. The initial balance should be
non-negative.
Public Methods
• getInterestRate – This is a “get” method used to get the interest rate.
• setInterestRate – This is a “set” method used to modify the interest rate.
• addInterest – Add the interest earned to the balance. New balance should be equal to
(1+interestRate)*balance.
Overridden Methods
The following methods are inherited either from the Object class or the Account class, and you
will need to overwrite them.
• toString – This method takes no parameter and returns a String object. It returns a String
object in the format of:
Account number:
Current balance:
Interest rate:
• displayInfo – this method takes no parameter. It prints the savings account information
in the following format:
Account number:
Current balance:
Interest rate:
4. AccountTest class
For the AccountTest class, you need to include a main method to test all the methods in
Account, CheckingAccount, and SavingsAccount class. You need to create multiple objects to be
able to test all the methods (including all the constructors and overridden methods) in all three
classes. You also need to test multiple cases for different possibilities when applicable. Please
also include a test case that transfers from a checking account to a savings account and vice
versa. Please also print sufficient messages about the output.
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Technical Notes
• At the top of EVERY Java file you create, you must include a comment which states your
name and what the program does. Follow the standard “Javadoc” commenting style
(/** ……. */) for formatting your comments.
• YOU MUST PROVIDE COMMENTS for EVERY method that is included in your
class. Follow the standard “Javadoc” commenting style (/** ……. */) for formatting
your comments and include @param for each parameter and @return if there is a return
type that is not void. You should also include Javadoc comments before each constructor.
• You do not need to finish writing the entire class before you can start testing it.
• Programs that do not compile will receive an automatic grade of “F”.
Submission instructions:
You need to submit your programs electronically on Canvas.
Please use a named package for each of your assignment. For example, for assignment 3,
create a new package and name your package as assg3_yourPirateId (use lower case for
your pirate id), such as assg3_smithj21. You also need to include a statement such as
“package assg3_smithj21;” at the beginning of each of your .java file (it will be
automatically generated in Eclipse if you create the class inside the given package). Please
follow this naming convention exactly for all future assignments. You will be deducted
points for not doing so.
When you submit your files to Canvas, please submit a zip file with your package folder
inside the zip file. The package folder should include only .java files (make sure you
include .java files, not .class files). The name of the folder should match with your
package name. (You can use 7-zip software to zip files/folder). Once your zip file is
unzipped, it will generate a folder that matches your package name.