Understanding try & catch and error handling

Question

import java.util.Scanner;

public class Lab4_5 {
    public static void main(String[]args) {
        Scanner scan= new Scanner(System.in);

        int rows=0;
              


        

Answer 1

You can create a try-catch block like so:

try {
    int num = scan.nextInt();
} catch (InputMismatchException ex) {
    // Exception handling here
}

If you want to implement this in your code, I suggest doing this:

while (true) {
    try {
        rows = scan.nextInt();
        if (rows<5||rows>21) {
            break;
        }
        else {
            System.out.println("That is either out of range or not an integer, try again! ");
        }
    } catch (InputMismatchException ex) {
        System.out.println("That is either out of range or not an integer, try again! ");
    }
}

See here for more details.