Question

1. Write a class named TestScores. The class constructor should accept an array test scores as its argument. The class should a method that returns the average of the test scores. If any test score is negative or greater than 100, the class should throw an IllegalArgumentException. Demonstrate this with an array of five items.
2. This is JAVA program.

Answer 1

import java.util.Scanner;

class Driver {

    public static void main(String[] args) {
        Scanner sc = new Scanner(System.in);
        int totalTestScores;
        try {

            System.out.println("Enter total number of Test Scores:");
            totalTestScores = sc.nextInt();
            int[] testScores = new int[totalTestScores];

            System.out.println("Please enter Test Scores:");
            for (int i = 0; i < testScores.length; i++) {
                testScores[i] = sc.nextInt();
            }
            TestScores testScoresObj = new TestScores(testScores);
            System.out.println("Average Test Score is : " + testScoresObj.averageTestScore());

        } catch (IllegalArgumentException e) {
            System.out.println("Test scores must have a value less than 100 and greater than 0.");
        }
    }
}

class TestScores {

    private int testScores[];

    public TestScores(int[] testScores) throws IllegalArgumentException {
        for (int i = 0; i < testScores.length; i++) {
            //If any of input value contain less than zero
            //or greater than 100 throw IllegalArgumentException
            if (testScores[i] < 0 || testScores[i] > 100) {
                throw new IllegalArgumentException();
            }
        }
        //If everything went fine then assign testScores to class testScores variable
        this.testScores = testScores;
    }

    public double averageTestScore() {
        int sum = 0;
        double average;
        for (int i = 0; i < testScores.length; i++) {
            sum = sum + testScores[i];
        }
        average = (double) sum / testScores.length;
        return average;
    }
}