Palindrome Program in Java: Number is Palindrome or Not

import java.util.Scanner;
class palindromeString

{
  public static void main(String args[])

  {
      String str, rev = "";

     Scanner sc = new Scanner(System.in);

     System.out.println("Enter a string:");

     str = sc.nextLine();

     int length = str.length();

     for ( int i = length - 1; i >= 0; i-- )

        rev = rev + str.charAt(i);

     if (str.equals(rev))
        System.out.println(str+" is a palindrome");

     else
        System.out.println(str+" is not a palindrome");
   }

}

public class PalindromeNumber {

    public static void main(String[] args)

    {
        int lastDigit,sum=0,a;

        int originalNumber=252; //The number you want to check whether it is palindrome or not
       
        a=originalNumber;
// Code to reverse a number

        while(a>0)

        { System.out.println("Original Number "+a);

              lastDigit=a%10; //get remainder

              System.out.println("Last Digit "+lastDigit);

              System.out.println("Digit "+lastDigit+ "  added in sum "+(sum*10));

              sum=(sum*10)+lastDigit;

              a=a/10;
}

// if given number equal to sum than number is palindrome otherwise not palindrome

            if(sum==originalNumber)

                System.out.println("Number is palindrome ");

            else

                System.out.println("Number is not palindrome");

}

}