code: public static TriaFrequency create(String first, char delimiter, String second, String third)
      {
          TriaFrequency triaFrequency = new TriaFrequency(first + delimiter + second + Occurrence.RIGHT + third);
          triaFrequency.first = first;
          triaFrequency.second = second;
          triaFrequency.third = third;
          triaFrequency.delimiter = delimiter;
          return triaFrequency;
      }
docs: 构造一个三阶接续，正向
  
  @param first
  @param second
  @param third
  @param delimiter 一般使用RIGHT！
  @return