ExcepHandle.java

import java.util.regex.Matcher;
import java.util.regex.Pattern;
import java.util.*;
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 in = new Scanner(System.in);
        System.out.println("Enter registration number and phone number");
        String reg = in.nextLine();
        String no = in.nextLine();
        validate(reg, no);
        System.out.println("Valid");
    }
}