code: public static String getSha(String str)
      {
          Check.notNull(str);
  
          return getSha(str.getBytes(StandardCharsets.UTF_8));
      }
docs: Get the SHA-256 signature of the input string.
  
  @param str The input string (must not be <code>null</code>).
  @return The string signature.
  @throws LionEngineException If invalid arguments.