check string is palindrome or not java code example

Example 1: Java program to check whether string is palindrome using library methods

public class StringPalindromeJava
{
   public static void isPalindrome(String str)
   {
      String strReverse = new StringBuffer(str).reverse().toString();
       // checking for palindrome
      if(str.equals(strReverse))
      {
         System.out.println(str + " is palindrome string.");
      }
      else
      {
         System.out.println(str + " is not palindrome string.");
      }
   }
   public static void main(String[] args)
   {
      // palindrome java
      isPalindrome("eye");
      isPalindrome("rotator");
   }
}

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));
}

Example 3: is palindrome method in java

package test
//The function below checks if a string is a palindrome
//True = Is a palindrome & False = Not a palindrome
	public boolean isPalindromString(String text){
    	String reverse = reverse(text);
      	if(text.equals(reverse))
    	{
        	return true;
      	}
      
      	return false;
    }
//This function returns the reverse String of its input.
//Ex. if given "hello", it will return "olleh"
	public String reverse(String input)
    {     
		if(input == null || input.isEmpty())
        {
			return input;
        }
return input.charAt(input.length()- 1) + reverse
                         (input.substring(0, input.length() - 1));
    }