code: public static String extractKey(String input) {
          int index = input.indexOf('=');
          if (-1 == index) {
              return input.trim();
          }
          return input.substring(0, index).trim();
      }
docs: Extract the key of a key=value pair contained withint the
  provided string. If no equals sign is found, then the input
  is returned with white space trimmed.
  
  @param input
  @return String