Java Problem 19

Here is the solution for Problem number 19.

/*
 * 19. Write a Java class called IsPalindrome, which 
 * defines a main() method that asks the user to enter 
 * a String s, and displays whether or not s is a 
 * palindrome. A palindrome is a String which reads the 
 * same forwards and backwards, such as "laval" or 
 * "stressed desserts".
 * 
 * Code taken from my previous solution of problem #21
 *
 * @author obispo 
 */

import javax.swing.*;
import java.text.*;
class IsPalindrome {
 public static void main( String[] args ) {
  String s1, s2;
  int result = 0, len, index1, index2;

  s1 = JOptionPane.showInputDialog(null, "Enter a string:");

  for (index1 = 0, index2 = s1.length() - 1; index1 < index2; index1++, index2--) {
   if (s1.charAt(index1) != s1.charAt(index2)) {
    result = -1;
    break;
   } 
  }   
  
  if (result == 0) {
   JOptionPane.showMessageDialog(null, "Palindrome !");  
  } else {
   JOptionPane.showMessageDialog(null, "Not Palindrome !");
  }
 }
}