Java error message java.lang.StringIndexOutOfBoundsException: String index out of range: 0
<p>here is my program</p>

<pre><code>import java.util.Scanner;
import java.util.Random;

public class Project3
{
    public static void main(String[] args)
    {

        int low;
        int high;
        int answer;
        int guess;
        int numGuess = 0;
        int x;
        int y;

       char repeat; // this will hold y or n 
       String input; //holds input to perform entire loop


        System.out.println( "Hello and welcome to Guess That Number!");

            Scanner keyboard = new Scanner(System.in);

        System.out.println("For starters you get to pick the range the number falls in!" +
                            " HOW EXCITING!");


        System.out.println( "Now what would you like the lowest possible number to be?");
                      low = keyboard.nextInt();

        System.out.println( "and the highest?");
                      high = keyboard.nextInt();
 do  
  {    Random randomNumber = new Random();

        answer = randomNumber.nextInt();
       while (answer &lt; low || answer &gt; high)
       { 
        answer = randomNumber.nextInt();
    }



       guess = -1;

       while(guess != answer)
       {

           System.out.println("What is your guess?");
          System.out.println("Don't forget has to be in between "+ low + " and " + high);

                   guess = keyboard.nextInt();

                   numGuess = (numGuess + 1);

                if (guess &lt; answer)
                {
                    System.out.println("TOO LOW!");

                }

                else if (guess &gt; answer)
                {
                    System.out.println("TOO HIGH!");



                }


            }





       System.out.println("YOU GOT IT WOOOO!");
       System.out.println("The number was " + answer);
       System.out.println("Nice it only took " + numGuess + "!");

       for ( x = 1; x &lt;= numGuess; x++)

      {

          for ( y = 1; y &lt;= answer; y++)

            {
                System.out.print("*");
            }

            System.out.println();



      }


      System.out.println("\nWould you like to play again? \n" +        // this is to loop the entire game
                      "Enter Y for yes or N for no. \n");

                      input = keyboard.nextLine();
                      repeat = input.charAt(0);

  } while (repeat == 'Y' || repeat == 'y');

    if (repeat == 'n' || repeat == 'N')             
    {

    System.out.println("\nThanks for playing! \n");

   }
}
}
</code></pre>

<p>when i try and run it it gives me this error message </p>

<p>java.lang.StringIndexOutOfBoundsException: String index out of range: 0
 at java.lang.String.charAt(String.java:687)</p>

<p>how do i fix it so the program loops correctly?!?</p>
