java palindrome program for string 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: String palindrome in java using array

// String palindrome in java using array
import java.util.Arrays;
import java.util.Scanner;
public class StringPalindromeUsingArray 
{
   public static void main(String[] args) 
   {
      System.out.println("Please enter string to check whether string is palindrome: ");
      Scanner sc = new Scanner(System.in);
      String strInput = sc.nextLine();
      char[] chArray = strInput.toCharArray();
      int size = chArray.length;
      char[] chGiven = Arrays.copyOf(chArray, chArray.length);
      for(int a = 0; a < size / 2; a++) 
      {
         char temp = chArray[a];
         chArray[a] = chArray[size - a - 1];
         chArray[size - a - 1] = temp;
      }
      System.out.println("Given array: " + Arrays.toString(chGiven));
      System.out.println("String palindrome using array: " + Arrays.toString(chArray));
      if(Arrays.equals(chArray, chGiven)) 
      {
         System.out.println("string is palindrome.");
      }
      else 
      {
         System.out.println("string is not a palindrome.");
      }
      sc.close();
   }
}

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Java Example