private Map<Long, String> getBoundariesStoragePolicyForMinor(boolean singleOutput,
    CompactionWindow window, long now) {
    Map<Long, String> boundariesPolicy = new HashMap<>();
    if (!comConf.isDateTieredStoragePolicyEnable()) {
      return boundariesPolicy;
    }
    String windowStoragePolicy = getWindowStoragePolicy(now, window.startMillis());
    if (singleOutput) {
      boundariesPolicy.put(Long.MIN_VALUE, windowStoragePolicy);
    } else {
      boundariesPolicy.put(window.startMillis(), windowStoragePolicy);
    }
    return boundariesPolicy;
  }
Returns a list of boundaries for multiple compaction output from minTimestamp to maxTimestamp.
hbase-server/src/main/java/org/apache/hadoop/hbase/regionserver/compactions/DateTieredCompactionPolicy.java