Question

Write an exception class that can be thrown when two negative numbers are passed to a method and write an ExceptionTest class to show that the exception class works.

Answer 1

Thanks for the question.
Here is the completed code for this problem. Comments are included, go through it, learn how things work and let me know if you have any doubts or if you need anything to change. If you are satisfied with the solution, please rate the answer. Thanks!
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// Exception class
//Write an exception class that can be thrown when two negative numbers are passed to a method
public class NegativeNumberException extends Exception {

    public NegativeNumberException() {
    }

    public NegativeNumberException(String message) {
        super(message);
    }
}

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public class ExceptionTest {


    public static void checkNumbers(int first, int second) throws NegativeNumberException {

        // check both numbers are negative if true then we throw NegativeNumber exception
        if (first < 0 && second < 0) {
            throw new NegativeNumberException("Error: " + first + " and " + second + " are both negative numbers.");
        }
        System.out.println("First Number = " + first);
        System.out.println("Second Number = " + second);
    }

    public static void main(String[] args) {


        try {
            checkNumbers(1, 2); // this method is fine it will print both the numbers
            checkNumbers(1, -2); // this method is fine it will print both the numbers
            checkNumbers(-1, -2); // this method will throw exception
        } catch (NegativeNumberException ne) {
            System.out.println(ne.getMessage());
        }

    }
}

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