private Set<String> getColumnFamilyList(Set<String> columns, HbckRegionInfo hbi)
    throws IOException {
    Path regionDir = hbi.getHdfsRegionDir();
    FileSystem fs = regionDir.getFileSystem(getConf());
    FileStatus[] subDirs = fs.listStatus(regionDir, new FSUtils.FamilyDirFilter(fs));
    for (FileStatus subdir : subDirs) {
      String columnfamily = subdir.getPath().getName();
      columns.add(columnfamily);
    }
    return columns;
  }
To get the column family list according to the column family dirs
@return a set of column families
hbase-server/src/main/java/org/apache/hadoop/hbase/util/HBaseFsck.java