(IllegalArgumentException) Modify the Loan class in Listing 10.2 to throw IllegalArgumentException if the loan amount, interest rate, or number of years is less than or equal to zero

/*********************************************************************************
* (IllegalArgumentException) Modify the Loan class in Listing 10.2 to throw      *
* IllegalArgumentException if the loan amount, interest rate, or number of years *
* is less than or equal to zero.                                                 *
*********************************************************************************/
import java.util.Scanner;

public class TestLoanClass {
	/** Main method */
	public static void main(String[] args) {
		// Create a Scanner
		Scanner input = new Scanner(System.in);
		boolean continueInput = true;

		do {
			// Enter annual interest rate
			System.out.print(
				"Enter annual interest rate, for example, 8.25: ");
			double annualInterestRate = input.nextDouble();
	
			// Enter number of years
			System.out.print("Enter number of years as an integer: ");
			int numberOfYeras = input.nextInt();
	
			// Enter loan amount
			System.out.print("Enter loan amount, for example, 120000.95: ");
			double loanAmount = input.nextDouble();
	

			try {
				// Create a Loan object
				Loan loan =
					new Loan(annualInterestRate, numberOfYeras, loanAmount);	
				continueInput = false;

				// Display loan date, monthly payment, and total payment
				System.out.printf("The loan was created on %s\n" + 
					"The monthly payment is %.2f\nTne total payment is %.2f\n",
					loan.getLoanDate().toString(), loan.getMonthlyPayment(),
					loan.getTotalPayment());
			}
			catch (IllegalArgumentException ex) {
				System.out.println(ex.getMessage());
			}
		} while (continueInput);
	}
}

Loan.java 

/**************************************
*            Loan                     *
*-----------------------------------  *
* -annualInterestRate: double         *
* -numberOfYears: int                 *
* -loanAmount: double                 *
* -loanDate: java.util.Date           *
* +Loan()                             *
* +Loan(annualInterestRate: double,   *
*   numberOfYears: int,loanAmount:    *
*   double)                           *
* +getAnnualInterestRate(): double    *
* +getNumberOfYears(): int            *
* +getLoanAmount(): double            *
* +getLoanDate(): java.util.Date      *
* +setAnnualInterestRate(             *
*   annualInterestRate: double): void *
* +setNumberOfYears(                  *
*   numberOfYears: int): void         *
* +setLoanAmount(                     *
* loanAmount: double): void           *
* +getMonthlyPayment(): double        *
* +getTotalPayment(): double          *
**************************************/

public class Loan {
	private double annualInterestRate;
	private int numberOfYears;
	private double loanAmount;
	private java.util.Date loanDate;

	/** Default constructor */
	public Loan() {
		this(2.5, 1, 1000);
	}

	/** Construct a loan with specified annual interest rate, 
	    number of years, and loan amount
	 */
	public Loan(double annualInterestRate, int numberOfYears,
		double loanAmount) {
		setAnnualInterestRate(annualInterestRate);
		setNumberOfYears(numberOfYears);
		setLoanAmount(loanAmount);
		loanDate = new java.util.Date();
	}

	/** Return annualInterestRate */
	public double getAnnualInterestRate() {
		return annualInterestRate;
	}

	/** Set an new annualInterestRate */
	public void setAnnualInterestRate(double annualInterestRate) 
			throws IllegalArgumentException {
		if (annualInterestRate <= 0) {
			throw new IllegalArgumentException(
				"Annual interest rate must be greater than 0");
		}
		this.annualInterestRate = annualInterestRate;
	}

	/** Return numberOfYears */
	public int getNumberOfYears() {
		return numberOfYears;
	}

	/** Set a new numberOfYears */
	public void setNumberOfYears(int numberOfYears) 
			throws IllegalArgumentException {
		if (numberOfYears <= 0) {
			throw new IllegalArgumentException(
				"Number of years must be greater than 0");
		}
		this.numberOfYears = numberOfYears;
	}

	/** Return loanAmount */
	public double getLoanAmount() {
		return loanAmount;
	}

	/** Set a new loanAmount */
	public void setLoanAmount(double loanAmount) 
			throws IllegalArgumentException {
		if (loanAmount <= 0) {
			throw new IllegalArgumentException(
				"Loan amount must be greater than 0");
		}
		this.loanAmount = loanAmount;
	} 

	/** Find monthly payment */
	public double getMonthlyPayment() {
		double monthlyInterestRate = annualInterestRate / 1200;
		double monthlyPayment = loanAmount * monthlyInterestRate / (1 -
			(1 / Math.pow(1 + monthlyInterestRate, numberOfYears * 12)));
		return monthlyPayment;
	}

	/** Find total payment */
	public double getTotalPayment() {
		double totalPayment = getMonthlyPayment() * numberOfYears * 12;
		return totalPayment;
	}
	
	/** Return loan date */
	public java.util.Date getLoanDate() {
		return loanDate;
	}
}