# Java & HTML introduction applet

*label*Other

*timer*Asked: May 30th, 2014

**Question description**

Your project as a programming consultant is to create a program that develops an amortization schedule. Your program should be written as a Java applet. As an applet, your program will be executed through the use of a browser. Your applet should prompt the user for three different inputs, loan amount, the duration of the loan and the annual interest rate. Your task is to create a Java applet that provides the user with a payment schedule, or amortization schedule. The schedule must include monthly payment amount, interest amount, principal amount and the remaining balance per pay period. The amortization table must be presented to the user in a nicely formatted table.

The applet input will be the loan amount, annual percentage rate (APR), and the number of years to pay out the loan. The output will be the loan amount, interest rate per pay period number of pay periods and the monthly payment. This information would be followed by the amortization schedule. Following is an example of the expected output for a $35,000 loan over 8 years at 8.5% interest rate.

Loan Amount: $35,000

Interest Rate per pay period: 0.085

Pay Periods: 96

Monthly Payment Amount: $503.72

Payment Monthly Amount Interest Principal Balance

35,000.00

1 503.72 247.92 255.80 34,744.20

2 503.72 246.10 257.62 34,486.58

3 503.72 244.28 259.44 33,965.86

….

95 503.72 7.07 496.65 500.78

96 503.72 3.55 500.17 0.61

The necessary calculations are below:

- p, loan amount or principal
- n, number of payments = payments per year * number of years
- i, interest rate per pay period = APR/payments per year = APR/12
- t, interest paid = interest rate per pay period * previous principal balance
- r, monthly payment amount = principal * interest per period / (1-(1+(interest per period)/100)^(number of payments-1)^2)
- a, principle amount = monthly payment amount – interest paid
- b, principle balance = previous balance – principle amount

**Hint:** In Java syntax the monthly payment calculation is:

`r=((p*(i/100))/(1-(Math.pow((1+(i/100)),(n*(-1))))));`

**Details:**

Please note that your program should accept three inputs:

- The loan amount,
- Annual Percentage Rate, and
- The number of years to pay out the loan

And calculate six types of outputs:

- The monthly payment amount,
- Interest per pay period,
- Number of pay periods,
- Amortization schedule (including amount of interest per pay period, principal per pay period, and principle balance)

When coding your applet, remember the following:

- Your applet needs to extend the Applet (or JApplet) class. Of course, you need to import the appropriate applet package(s).
- Your applet needs to have declarations for the fields, labels, components, widgets, and so forth that you use in the applet.
- There are applet methods that are called automatically by browsers (please see your textbook). Make sure you initialize (
*implement init()*) your applet. - You need the code that does the calculation of the interest.
- You need to handle the event of pressing the button. There are some examples in the book (ask your instructor for the specific pages).
- You may use this sample code for example.

**Please create an HTML page that contains the applet tag. In addition to your mortgage calculator commented Java code, you need to provide the HTML page.**

Here is the Hello world Java code example to create an applet:

`import java.applet.*;`

import java.awt.*;

/**

* The HelloWorld class implements anapplet that

* simply displays "HelloWorld!".

*/

public class HelloWorld extends Applet {

public void paint(Graphics g){

// Display "Hello World!"

g.drawString("Hello world!",50, 25);

}

}

Then you would compile the class and create an HTML page called Hello.htm:

`<HTML>`

<HEAD>

<Title>A Simple Program.</Title>

</HEAD>

<BODY>

Here is the output of my program:

<APPLET CODE="HelloWorld.class"WIDTH="150" HEIGHT="25">

</APPLET>

</BODY>

</HTML>

Deliverable Details:

Upload the __commented__ source code file of your calculator, the class file and the HTML file.