Question

This is for java programming

Please Show plenty of comments so I can follow the steps

Design a class named Account that contains:

• A private int data field named id for the account (default 0)

• A private double data field named balance for the account (default 0)

• A private double data field named annualInterestRate that stores the current interest rate (default 0). Assume all accounts have the same interest rate.

• A private Date data field named dateCreated that stores the date when the account was created.

• A no-arg constructor that creates a default account.

• A constructor that creates and account with the specified id and initial balance.

• The accessor and mutator methods for id, balance, and annualInterestRate.

• The accessor method for dateCreated.

• A method named getMonthlyInterestRate() that returns the monthly interest rate.

• A method named getMonthlyInterest() that returns the monthly interest.

• A method named withdraw that withdraws a specified amount from the account.

• A method named deposit that deposits a specified amount to the account.

Draw the UML diagram for the class and then implement the class. (Hint: the method getMonthlyInterest() is to return monthly interest, not the interest rate. Monthly interest is balance * monthlyInterestRate, where monthlyInterestRate is annualInterestRate / 12. Note that annualInterestRate is a percentage, e.g. 4.5%. You need to divide it by 100).

Write a test program that creates an Account object with an account ID of 1122, a balance of $20,000, and an annual interest rate of 4.5%. Use the withdraw method to withdraw $2,500, use the deposit method to deposit $3,000, and print the balance, the monthly interest, and the date when this account was created.

Answer 1

Source Code in Java:

import java.util.Date;
class Account
{
//member variables
private int id;
private double balance,annualInterestRate;
private Date dateCreated;
Account() //default constructor
{
//setting variables to default values
id=0;
balance=0;
annualInterestRate=0;
dateCreated=new Date(); //setting to current date
}
Account(int id,double balance) //parametrized constructor
{
this(); //calling default constructor
//setting variables to parameter values
this.id=id;
this.balance=balance;
}
//accessor methods - to access the value of the variables
int getId()
{
return id;
}
double getBalance()
{
return balance;
}
double getAnnualInterestRate()
{
return annualInterestRate;
}
Date getDateCreated()
{
return dateCreated;
}
//mutator methods - to change the value of the variables
void setId(int id)
{
this.id=id;
}
void setBalance(double balance)
{
this.balance=balance;
}
void setAnnualInterestRate(double annualInterestRate)
{
this.annualInterestRate=annualInterestRate;
}
//helper methods
//method to calculate and return monthly interest rate
double getMonthlyInterestRate()
{
return annualInterestRate/12;
}
//method to calculate and return monthly interest
double getMonthlyInterest()
{
return balance*getMonthlyInterestRate()/100;
}
//method to withdraw a certain amount from the account
void withdraw(double amount)
{
if(amount>balance) //checking if withdraw is not possible
System.out.println("Withdraw cannot be done, not enough balance!");
else
{
balance-=amount;
System.out.println(amount+" successfully withdrawn!");
}
}
//method to deposit a certain amount into the account
void deposit(double amount)
{
balance+=amount;
System.out.println(amount+" successfully deposited!");
}
}

class AccountTest
{
public static void main(String args[])
{
//testing the Account class
Account test=new Account(1122,20000);
test.setAnnualInterestRate(4.5);
test.withdraw(2500);
test.deposit(3000);
System.out.println("Balance: "+test.getBalance());
System.out.println("Monthly Interest: "+test.getMonthlyInterest());
System.out.println("Date created: "+test.getDateCreated());
}
}

Output: