static Path tryCreateRecoveredHFilesDir(FileSystem rootFS, Configuration conf,
    TableName tableName, String encodedRegionName, String familyName) throws IOException {
    Path rootDir = CommonFSUtils.getRootDir(conf);
    Path regionDir = FSUtils.getRegionDirFromTableDir(CommonFSUtils.getTableDir(rootDir, tableName),
      encodedRegionName);
    Path dir = getRecoveredHFilesDir(regionDir, familyName);
    if (!rootFS.exists(dir) && !rootFS.mkdirs(dir)) {
      LOG.warn("mkdir failed on {}, region {}, column family {}", dir, encodedRegionName,
        familyName);
    }
    return dir;
  }
Return path to recovered.hfiles directory of the region's column family: e.g.
/hbase/some_table/2323432434/cf/recovered.hfiles/. This method also ensures existence of
recovered.hfiles directory under the region's column family, creating it if necessary.
@param rootFS            the root file system
@param conf              configuration
@param tableName         the table name
@param encodedRegionName the encoded region name
@param familyName        the column family name
@return Path to recovered.hfiles directory of the region's column family.
hbase-server/src/main/java/org/apache/hadoop/hbase/wal/WALSplitUtil.java