code: public static String intersectSeq(final String first, final String second, final String delimiter) {
      if (isEmpty(first) || isEmpty(second)) { return ""; }
      List<String> firstSeq = Arrays.asList(split(first, ','));
      List<String> secondSeq = Arrays.asList(split(second, ','));
      Collection<String> rs = CollectUtils.intersection(firstSeq, secondSeq);
      StringBuilder buf = new StringBuilder();
      for (final String ele : rs) {
        buf.append(delimiter).append(ele);
      }
      if (buf.length() > 0) {
        buf.append(delimiter);
      }
      return buf.toString();
    }
docs: 返回一个新的逗号相隔字符串，实现其中的单词a-b的功能
  
  @param first a {@link java.lang.String} object.
  @param second a {@link java.lang.String} object.
  @param delimiter a {@link java.lang.String} object.
  @return a {@link java.lang.String} object.