code: public void merge(String mergeResultPath, String... resultPaths){
          try{
              Map<String, AtomicInteger> map = new ConcurrentHashMap<>();
              for(String resultPath : resultPaths) {
                  Files.lines(Paths.get(resultPath)).forEach(line -> {
                      String[] attrs = line.split("\\s+");
                      if (attrs != null && attrs.length == 2) {
                          statistics(attrs[0], Integer.parseInt(attrs[1]), map);
                      }
                  });
              }
              dump(map, mergeResultPath);
          }catch (Exception e){
              LOGGER.error("merge error!", e);
          }
      }
docs: 将多个词频统计结果文件进行合并
  @param mergeResultPath 合并结果文件路径
  @param resultPaths 多个词频统计结果文件路径