@Override
  protected boolean shouldIncludeStore(HRegionFileSystem fileSystem, String family,
    Collection<StoreFileInfo> storeFiles, long ts) throws IOException {

    for (StoreFileInfo storeFile : storeFiles) {
      // Lets only compact when all files are older than TTL
      if (storeFile.getModificationTime() >= ts) {
        LOG.info("There is atleast one file in store: " + family + " file: " + storeFile.getPath()
          + " with timestamp " + storeFile.getModificationTime() + " for region: "
          + fileSystem.getRegionInfo().getEncodedName() + " older than TTL: " + ts);
        return false;
      }
    }
    return true;
  }
This request helps determine if a region has to be compacted based on table's TTL.
hbase-server/src/main/java/org/apache/hadoop/hbase/util/compaction/MajorCompactionTTLRequest.java