code: private static boolean isSeparator(char character, char... separators)
    {
      if(separators.length == 0) {
        separators = DEFAULT_SEPARATORS;
      }
      for(int i = 0; i < separators.length; ++i) {
        if(character == separators[i]) {
          return true;
        }
      }
      return false;
    }
docs: Test if <code>character</code> is a separator as defined by given <code>separators</code> list. If separator list
  is empty consider used {@link #DEFAULT_SEPARATORS}. This predicate is designed specifically for
  {@link #split(String, char...)} operation.
  
  @param character character to test if usable as separator,
  @param separators variable number of separator characters.
  @return true if <code>character</code> is a separator, as defined by this method.