捕获异常后重复执行main方法

Question

This program takes in an integer and returns the number of digits within that integer. I noticed that I was unable to take very big numbers, so I decided to use the BigInteger class. All was good until I realized I needed the user to input a valid integer if they use incompatible input (like a string). How do I make the main method repeat after the catch statement, so no matter how many times you use bad input it request another input? I know that I shouldn't exit the program.

//This class test the recursive method to see how many digits are in a number
public class TestDigits {

    public static void main(String[] args) {// main method to test the nmbDigits method
        Scanner intInput = new Scanner(System.in);
        try{
        System.out.println("Input an integer number:");
        BigInteger number = intInput.nextBigInteger() ;
        System.out.println(nmbDigits(number));}

        catch (InputMismatchException ex){
        System.out.println("incorrect input, integer values only.");
        System.exit(1);}}



static BigInteger nmbDigits(BigInteger c) {//nmbDigits method takes input from user and returns the number of digits
    long digits = 0;

    if (c.divide(BigInteger.valueOf(10l)) == BigInteger.valueOf(0l)){
        digits++;
    }
    else if (c.divide(BigInteger.valueOf(10l)) != BigInteger.valueOf(0l)){
        digits++;
          BigInteger remainingValue = c.divide(BigInteger.valueOf(10l));
          BigInteger g =   nmbDigits(remainingValue);
          digits += g.longValue();}
    return BigInteger.valueOf(digits);}}    

Answer 1

You can loop :

public static void main(String[] args) {// main method to test the nmbDigits method
    boolean exit=false;
    Scanner intInput = new Scanner(System.in);
    while (!exit) {
      try{
        System.out.println("Input an integer number:");
        BigInteger number = intInput.nextBigInteger() ;
        System.out.println(nmbDigits(number));
        exit=true;
      }
      catch (InputMismatchException ex){
        System.out.println("incorrect input, integer values only.");
      }
    }
}

Answer 2

Somewhat like this pseudocode would do:

main(args) {
   input = null;
   do {
      input = getInput(); 
   } while(!valid(input);
   solveAlgorithm(input);
}