code: public static String toStringUTF8(byte[] input)
      {
          if (input == null)
          {
              return null;
          }
  
          try
          {
              return new String(input, "UTF-8");
          }
          catch (UnsupportedEncodingException e)
          {
              // This won't happen.
              return null;
          }
      }
docs: Build a {@code String} instance by {@code new String(input, "UTF-8")}.