Question

Using Java

Summary

Create a Loan class, instantiate and write several Loan objects to a file, read them back in, and format a report.

Project Description

You’ll read and write files containing objects of the Loan class. Here are the details of that class:

Instance Variables:

customer name (String) annual interest percentage (double) number of years (int) loan amount (double) loan date (String) monthly payment (double) total payments (double)

Methods:

• getters for all instance variables
• setters for all instance variables except monthly payment and total payment
• calculateMonthlyPayment and calculateTotalPayments

The setters for the annual interest percentage, number of years, and loan amount invoke both “calculate…” methods before they exit

The “calculate…” methods compute the named value, then store that amount in the associated instance variable. They are private (helper) methods.

Constructors:

• a “no-arg” constructor sets the customer name to a default value, the loan date to “no date”, and all numeric variables to zero. This method invokes the “full” constructor
• a “full” constructor takes the customer name, annual interest percentage, number of years, loan amount, and loan date. It invokes the appropriate setters, but doesn’t need to invoke the “calculate” methods (why?)

Calculations:

monthly interest rate = annual interest percentage / 1200 monthly payment = (loan amount * monthly interest rate) / (1 – Math.pow( (1 + monthly interest rate), – (number of years * 12) ) ) total loan payments = monthly payment * number of years * 12

* Note: Round all dollar amounts to 2 decimal places

Here is what you should do in main

Use this data to create five Loan objects

Annual Interest Loan Customer Name Percentage Years Amount Loan Date Bob Smith 6.5% 30 318,000 Sep 1, 2015 Alicia Herman 4.2% 15 248,000 Oct 15, 2013 Julie Franciosa 8.5% 10 30,000 Apr 14, 2010 Julio Quiros 15.0% 3 50,000 June 23, 2017 Frank Larsen 8.9% 5 23,000 Mar 8, 2016

Use this algorithm:

1. Make the Loan class Serializable (don't forget to import this interface from java.io).
2. Instantiate Loan objects representing the first three loans above using the “full” constructor
3. Create an output stream and store the three objects into a binary file using the writeObject method
4. Instantiate Loan objects representing the last two loans above using the “no-arg” constructor, then use setters to update information about those loans
5. Append those objects to the output stream created above in step 2
6. Close the output stream
7. Create an input stream and read the objects from the binary file above and display in a nicely formatted columnar report

• Write your code to handle any number of loan objects (i.e., do not assume that there are 5 Loan objects in the file -- use a loop).
• Include in your report the monthly loan payment and total loan payment amounts
• Display totals for the amount of the loan amounts, monthly payments, and total loan payments.

8. Close the input stream

Note: After writing the first three Loan objects to a file (in step 2), close the output stream, then re-open the output stream before step 4 appending the last two Loan objects to the existing file

An example of the output from your program

Annual Monthly Total Customer Name Prcnt Yrs Loan-Amount Payment Loan Payments Loan-Date ---------------- ----- --- ----------- --------- ------------ ------------- Bob Smith 6.5 30 318,000.00 2,009.98 723,592.80 Sep 1, 2015 Alicia Herman 4.2 15 248,000.00 1,859.38 334,688.40 Oct 15, 2013 Julie Franciosa 8.5 10 30,000.00 446.35 53,562.00 Apr 14, 2010 Julio Quiros 15.0 3 50,000.00 1,660.72 59,785.92 June 23, 2017 Frank Larsen 8.9 5 23,000.00 476.33 28.579.80 Mar 8, 2016 =========== ========= ============ 669,000.00 6,452.76 1,200,208.92

Answer 1

//Java code

import java.text.NumberFormat;

public class Loan {
    private String customerName;
    private double annualInterest;
    private int numberOfYears;
    private double loanAmount;
    private String loanDate;
    private double monthlyPayment;
    private double totalPayments;


    //getters

    public String getCustomerName() {
        return customerName;
    }

    public double getAnnualInterest() {
        return annualInterest;
    }

    public int getNumberOfYears() {
        return numberOfYears;
    }

    public double getLoanAmount() {
        return loanAmount;
    }

    public String getLoanDate() {
        return loanDate;
    }

    public double getMonthlyPayment() {
        return monthlyPayment;
    }

    public double getTotalPayments() {
        return totalPayments;
    }

    //setters

    public void setCustomerName(String customerName) {
        this.customerName = customerName;
    }

    public void setAnnualInterest(double annualInterest) {

        this.annualInterest = annualInterest;
        calculateMonthlyPayment();
        calculateTotalPayments();
    }

    public void setNumberOfYears(int numberOfYears) {
        this.numberOfYears = numberOfYears;
        calculateMonthlyPayment();
        calculateTotalPayments();
    }

    public void setLoanAmount(double loanAmount) {
        this.loanAmount = loanAmount;
        calculateMonthlyPayment();
        calculateTotalPayments();

    }

    public void setLoanDate(String loanDate) {
        this.loanDate = loanDate;
    }
    private void calculateMonthlyPayment()
    {
        double monthlyInterestRate = annualInterest/1200.0;
        monthlyPayment = (loanAmount*monthlyInterestRate)/(1-Math.pow((1+monthlyInterestRate),-(numberOfYears*12)));

    }
    private void calculateTotalPayments()
    {

       this.totalPayments = this.numberOfYears*this.monthlyPayment*12.0;

    }
    ///no args constructor

    /***
     * a “no-arg” constructor sets the customer name to a default value,
     * the loan date to “no date”, and
     * all numeric variables to zero. This method invokes the “full” constructor
     */
    public Loan()
    {
        this("",0,0,0,"no date");

    }
    //full constructor

    /**
     * a “full” constructor takes the customer name, annual
     * interest percentage, number of years, loan amount,
     * and loan date. It invokes the appropriate setters,
     * @param customerName
     * @param annualInterest
     * @param numberOfYears
     * @param loanAmount
     * @param loanDate
     */
    public Loan(String customerName, double annualInterest, int numberOfYears, double loanAmount, String loanDate) {
       setAnnualInterest(annualInterest);
       setCustomerName(customerName);
       setLoanAmount(loanAmount);
       setLoanDate(loanDate);
       setNumberOfYears(numberOfYears);


    }






    public void display()
    {
        System.out.println(String.format("%16s %5s %6s %15s %17s %17s %17s",customerName,String.format("%.2f",annualInterest),numberOfYears, NumberFormat.getCurrencyInstance().format(loanAmount),NumberFormat.getCurrencyInstance().format(monthlyPayment),NumberFormat.getCurrencyInstance().format(totalPayments),loanDate));
    }
    @Override
    public String toString() {
        return customerName+" "+annualInterest+" "+numberOfYears+" "+loanAmount+" "+loanDate;
    }
}

//==================================

import java.io.File;
import java.io.FileWriter;
import java.io.IOException;
import java.io.PrintWriter;
import java.text.NumberFormat;
import java.util.Scanner;

public class LoanTest {
    public static void main(String[] args) throws IOException {
       Loan loan1 = new Loan("Bob Smith",6.5,30,318000,"Sep 1, 2015");
        Loan loan2 = new Loan("Alicia Herman",4.2,15,248000,"Oct 15,2013");
        Loan loan3 = new Loan("Julie Franciosca",8.5,10,30000,"Apr 14,2010");
        PrintWriter printWriter = new PrintWriter(new FileWriter("loan.txt"));
        Loan loan4 = new Loan();
        loan4.setCustomerName("Julio Quiros");
        loan4.setNumberOfYears(3);
        loan4.setLoanAmount(50000);
        loan4.setAnnualInterest(15);
        loan4.setLoanDate("June 23, 2017");
        //============================
        Loan loan5 = new Loan();
        loan5.setCustomerName("Frank Larsen");
        loan5.setNumberOfYears(5);
        loan5.setLoanAmount(23000);
        loan5.setAnnualInterest(8.9);
        loan5.setLoanDate("Mar 8, 2016");



        //write data to file
        printWriter.println(loan1);
        printWriter.println(loan2);
        printWriter.println(loan3);
        printWriter.println(loan4);
        printWriter.println(loan5);
        printWriter.close();
        double totalLoanAmount =0,totalLoanPayment=0,totalMonthlyPayment=0;
        //header
        System.out.println(String.format("%16s %5s %6s %15s %15s %15s %15s","Customer Name","Percent","Years","Loan Amount","Payment","Loan Payments","Loan Date"));
        System.out.println(String.format("%16s %5s %4s %15s %15s %15s %15s","------------","---------","-----","-----------","-------","-------------","---------"));
        //Open stream to read
        Scanner scanFile = new Scanner(new File("loan.txt"));
        while (scanFile.hasNextLine())
        {
            String line  = scanFile.nextLine();
            Scanner words  = new Scanner(line);
            //Create loan
            Loan loan = new Loan(words.next()+" "+words.next(),words.nextDouble(),words.nextInt(),words.nextDouble(),words.nextLine());
            totalLoanAmount+=loan.getLoanAmount();
            totalLoanPayment+=loan.getTotalPayments();
            totalMonthlyPayment+=loan.getMonthlyPayment();
            loan.display();

        }
        System.out.println(String.format("%16s %5s %6s %15s %17s %17s %15s","","","","============","=============","============",""));
        System.out.println(String.format("%16s %5s %6s %15s %17s %17s %15s","","","", NumberFormat.getCurrencyInstance().format(totalLoanAmount),NumberFormat.getCurrencyInstance().format(totalMonthlyPayment),NumberFormat.getCurrencyInstance().format(totalLoanPayment),""));
        scanFile.close();

    }
}

//loan.txt

//Output

//If you need any help regarding this solution .......... please leave a comment ...... thanks