assignment3-intellij/src/ExcepHandle.java

import java.util.NoSuchElementException;
import java.util.Scanner;
import java.util.regex.Matcher;
import java.util.regex.Pattern;

public class ExcepHandle {

    static void validate(String r, String n) {
        if (r.length() != 9) {
            System.out.println("Invalid");
            throw new IllegalArgumentException("Register Number does not contain exactly 9 characters");
        }
        if (n.length() != 10) {
            System.out.println("Invalid");
            throw new IllegalArgumentException("Mobile Number does not contain exactly 10 characters");
        }

        String pattern = "^[6|7|8|9]{1}\\d{9}";
        Pattern a = Pattern.compile(pattern);
        Matcher m1 = a.matcher(n);
        if (!m1.find()) {
            throw new NumberFormatException("Mobile Number cannot contain any character other than a digit");
        }

        String pattern2 = "^[1-9]{2}[A-Z]{3}[0-9]{4}$";
        Pattern b = Pattern.compile(pattern2);
        Matcher m2 = b.matcher(r);
        if (!m2.find()) {
            throw new NoSuchElementException(
                    "Registration Number cannot contain any character other than digits and alphabets");
        }

    }

    public static void main(String args[]) {
        Scanner sc = new Scanner(System.in);
        String reg = sc.nextLine();
        String no = sc.nextLine();
        sc.close();
        validate(reg, no);
        System.out.println("Valid");
    }
}