Question

Define the EvenNumber class for representing an even number. The class contains:

• A data field value of the int type that represents the integer value stored in the object.
• A no-arg constructor that creates an EvenNumber object for the value 0.
• A constructor that constructs an EvenNumber object with the specified value.
• A function named getValue() to return an int value for this object.
• A function named getNext() to return an EvenNumber object that represents the next even number after the current even number in this object.
• A function named getPrevious() to return an EvenNumber object that represents the previous even number before the current even number in this object.

Write a test program that creates an EvenNumber object for value 16 and invokes the getNext() and getPrevious() functions to obtain and displays these numbers.

Answer 1

class EvenNumber {

    private int value;

    public EvenNumber() {
        value = 0;
    }

    public EvenNumber(int value) {
        this.value = value;
    }

    public int getValue() {
        return value;
    }

    public EvenNumber getNext() {
        return new EvenNumber(value + 2);
    }

    public EvenNumber getPrevious() {
        return new EvenNumber(value - 2);
    }
}


class TestEvenNumber {

    public static void main(String[] args) {
        EvenNumber evenNumber = new EvenNumber(16);
        System.out.println(evenNumber.getNext().getValue());
        System.out.println(evenNumber.getPrevious().getValue());
    }
}