public void initTrailerAndContext(ReaderContext context, Configuration conf) throws IOException {
    try {
      boolean isHBaseChecksum = context.getInputStreamWrapper().shouldUseHBaseChecksum();
      trailer = FixedFileTrailer.readFromStream(
        context.getInputStreamWrapper().getStream(isHBaseChecksum), context.getFileSize());
      Path path = context.getFilePath();
      checkFileVersion(path);
      this.hfileContext = createHFileContext(path, trailer, conf);
      context.getInputStreamWrapper().unbuffer();
    } catch (Throwable t) {
      IOUtils.closeQuietly(context.getInputStreamWrapper(),
        e -> LOG.warn("failed to close input stream wrapper", e));
      throw new CorruptHFileException(
        "Problem reading HFile Trailer from file " + context.getFilePath(), t);
    }
  }
Fill our map with content of the pb we read off disk
@param fip protobuf message to read
hbase-server/src/main/java/org/apache/hadoop/hbase/io/hfile/HFileInfo.java