how to find palindrome string in java code example

Example 1: Java program to check palindrome string using recursion

import java.util.Scanner;
public class RecursivePalindromeJava 
{
   // to check if string is palindrome using recursion
   public static boolean checkPalindrome(String str)
   {
      if(str.length() == 0 || str.length() == 1)
         return true; 
      if(str.charAt(0) == str.charAt(str.length() - 1))
         return checkPalindrome(str.substring(1, str.length() - 1));
      return false;
   }
   public static void main(String[]args)
   {
      Scanner sc = new Scanner(System.in);
      System.out.println("Please enter a string : ");
      String strInput = sc.nextLine();
      if(checkPalindrome(strInput))
      {
         System.out.println(strInput + " is palindrome");
      }
      else
      {
         System.out.println(strInput + " not a palindrome");
      }
      sc.close();
   }
}

Example 2: generate palindrome java

//This function generates a palindrom by recursively reversing a String,
//recursively add it and checks if it's a palindrom

public static String generatePalindrom(String s) {
	return s.equals(reverseString(s)) ? s
				: generatePalindrom(String.valueOf(Integer.parseInt(s) + Integer.parseInt(reverseString(s))));
}

public static String reverseString(String s) {
	return s.length() == 1 ? s : s.charAt(s.length() - 1) + reverseString(s.substring(0, s.length() - 1));
}

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Java Example