private static String getPathOffsetEndStr(final Path path, final long offset, final long end) {
    return "path=" + path.toString() + ", offset=" + offset + ", end=" + end;
  }
Implementation of {@link HFile.Reader} to deal with pread.
hbase-server/src/main/java/org/apache/hadoop/hbase/io/hfile/HFilePreadReader.java