Question

Modify the mortgage program to display 3 mortgage loans: 7 years at 5.35%, 15 year at 5.5%, and 30 years at 5.75%. Use an array for the different loans. Display the mortgage payment amount for each loan. Do no use graphical user interface. Insert comments in the program to document the program.

***********Please look at my code so far. Still having trouble with arrays. Want to know if I'm going the right path********

import java.util.Scanner;
public class MortPay2
{
public static void main(String args[])
{
//declaration section
double principal, monthlyPayment;
int choice;
Scanner input = new Scanner(System.in);

   int term [] = {84, 180, 360}; //term in months
   double rate [] = {.0044, .0046, .0048};//rate in decimal format

  
   //display section
   System.out.println("Please select from 3 loan options.");
   System.out.println("1. Loan 1: 7 year term at 5.35% interest.");
   System.out.println("2. Loan 2: 15 year term at 5.5% interest.");
   System.out.println("3. Loan 3: 30 year term at 5.75% interest.");
   choice = input.nextInt();

   if (choice ==1)
   {
       System.out.println("You have chosen Loan 1.");
       System.out.println("Please enter the loan amount: $");
       principal = input.nextDouble();

       for ( int i = 0; i<3; i++)
       {
           monthlyPayment = principal * rate[0] / (1.0 - Math.pow (rate[0] + 1), -term[0]));
           System.out.println("Total monthly mortgae payment is $%.2f%n", monthlyPayment);
}
   }
  
  
}
}
  
      
  

Answer 1

JAVA PROGRAM

/////////////////////////////MortPay2.java////////////////////////////

import java.util.Scanner;
public class MortPay2{
   public static void main(String args[]){
   //declaration section
   double principal, monthlyPayment;
   int choice;
   Scanner input = new Scanner(System.in);
      
   int term [] = {84, 180, 360}; //term in months
   double rate [] = {.0044, .0046, .0048};//rate in decimal format; stored as (yearlyRate/12)
  
  
   //display section
   System.out.println("Please select from 3 loan options.");
   System.out.println("1. Loan 1: 7 year term at 5.35% interest.");
   System.out.println("2. Loan 2: 15 year term at 5.5% interest.");
   System.out.println("3. Loan 3: 30 year term at 5.75% interest.");
   System.out.println("4. Display all Loans");//added this option to show all options at a time
     
   choice = input.nextInt();
     
   int index = 0,termInMonth;
   double mortgageRate;
     
   if (choice ==1){
   System.out.println("You have chosen Loan 1.");
   index =0; //as we need to consider 0th index element from both term and rate array
   }else if(choice ==2){
       System.out.println("You have chosen Loan 2.");
   index =1; //as we need to consider 1st index element from both term and rate array
   }else if(choice ==3){
       System.out.println("You have chosen Loan 3.");
   index =2; //as we need to consider 2nd index element from both term and rate array
   }else {
       System.out.println("You have chosen to display all loans.");
       index = -1; //this is set in this way to show all loans
   }
     
System.out.println("Please enter the loan amount: $");
principal = input.nextDouble();

   if(index==-1){//if index = -1 show all loans
   for(int i = 0; i < 3 ; i++){//loop from i = 0 to 2
       //calculate monthly payment for ith index loan
           monthlyPayment = principal * rate[i]/ (1.0 - Math.pow (rate[i] + 1, -term[i]));
           //print the monthly payment
           System.out.printf("\nLoan %d : Total monthly mortgae payment is $%.2f%n", i+1,monthlyPayment);
   }
   }else{//otherwise display for specific loan
       mortgageRate = rate[index];//get rate for the index
       termInMonth = term[index];//get term for the index
       //calculate monthly payment
       monthlyPayment = principal * mortgageRate/ (1.0 - Math.pow (mortgageRate+ 1, -termInMonth));
       //print it
       System.out.printf("\nLoan %d : Total monthly mortgae payment is $%.2f%n", index+1,monthlyPayment);
   }
  
   input.close();//close scanner
   System.out.println("\nThank you!");
   }
}

=====================================

OUTPUT

====================================

Run1

Please select from 3 loan options.
1. Loan 1: 7 year term at 5.35% interest.
2. Loan 2: 15 year term at 5.5% interest.
3. Loan 3: 30 year term at 5.75% interest.
4. Display all Loans
1
You have chosen Loan 1.
Please enter the loan amount: $
15000

Loan 1 : Total monthly mortgae payment is $213.99

Thank you!

Run2

Please select from 3 loan options.
1. Loan 1: 7 year term at 5.35% interest.
2. Loan 2: 15 year term at 5.5% interest.
3. Loan 3: 30 year term at 5.75% interest.
4. Display all Loans
2
You have chosen Loan 2.
Please enter the loan amount: $
16000

Loan 2 : Total monthly mortgae payment is $130.90

Thank you!

Run3

Please select from 3 loan options.
1. Loan 1: 7 year term at 5.35% interest.
2. Loan 2: 15 year term at 5.5% interest.
3. Loan 3: 30 year term at 5.75% interest.
4. Display all Loans
3
You have chosen Loan 3.
Please enter the loan amount: $
17000

Loan 3 : Total monthly mortgae payment is $99.32

Thank you!

Run4

Please select from 3 loan options.
1. Loan 1: 7 year term at 5.35% interest.
2. Loan 2: 15 year term at 5.5% interest.
3. Loan 3: 30 year term at 5.75% interest.
4. Display all Loans
4
You have chosen to display all loans.
Please enter the loan amount: $
20000

Loan 1 : Total monthly mortgae payment is $285.32

Loan 2 : Total monthly mortgae payment is $163.63

Loan 3 : Total monthly mortgae payment is $116.84

Thank you!