get sha256 representation of a string in java

sha256.java

public static String getSHA(String input) 
    {
    // ------ Geeks For Geeks code ---------
        try { 
  
            // Static getInstance method is called with hashing SHA 
            MessageDigest md = MessageDigest.getInstance("SHA-256"); 
  
            // digest() method called 
            // to calculate message digest of an input 
            // and return array of byte 
            byte[] messageDigest = md.digest(input.getBytes()); 
  
            // Convert byte array into signum representation 
            BigInteger no = new BigInteger(1, messageDigest); 
  
            // Convert message digest into hex value 
            String hashtext = no.toString(16); 
  
            while (hashtext.length() < 32) { 
                hashtext = "0" + hashtext; 
            } 
  
            return hashtext; 
        } 
  
        // For specifying wrong message digest algorithms 
        catch (NoSuchAlgorithmException e) { 
            System.out.println("Exception thrown" + " for incorrect algorithm: " + e); 
            return null; 
        } 
    }