/**
 * 
 */

/**
 * @author arau-chaplin
 *
 */
//*******************************************************************
//
//   Palindromes.java          In Text          Application
//
//   Authors:  Lewis and Loftus
//
//   Classes:  Palindromes
//             Palindrome_Tester
//
//*******************************************************************

//-------------------------------------------------------------------
//
//  Class Palindromes demonstrates recursive calls.
//
//  Methods:
//
//     public static void main (String[] args)
//
//-------------------------------------------------------------------

public class Palindromes {

   //===========================================================
   //  Creates a Palindrome_Tester object, and tests several
   //  strings.
   //===========================================================
   public static void main (String[] args) {

      Palindrome_Tester tester = new Palindrome_Tester();
      
      System.out.println ("radar is a palindrome? "
         + tester.ptest ("radar"));

      System.out.println ("abcddcba is a palindrome? "
         + tester.ptest ("abcddcba"));

      System.out.println ("able was I ere I saw elba is a palindrome? "
         + tester.ptest ("able was I ere I saw elba"));

      System.out.println ("hello is a palindrome? "
         + tester.ptest ("hello"));

      System.out.println ("abcxycba is a palindrome? "
         + tester.ptest ("abcxycba"));

   }  // method main

}  // class Palindromes

//-------------------------------------------------------------------
//
//  Class Palindrome_Tester contains a method to test to see if
//  a string is a palindrome.
//
//  Methods:
//
//     public boolean ptest (String str)
//
//-------------------------------------------------------------------

class Palindrome_Tester {

   //===========================================================
   //  Uses recursion to perform the palindrome test.
   //===========================================================
   public boolean ptest (String str) {

      boolean result = false;

      if (str.length() <= 1)
         result = true;
      else
         if (str.charAt (0) == str.charAt (str.length()-1))
            result = ptest (str.substring (1, str.length()-1));

      return result;

   }  // method ptest

}  // class Palindrome_Tester