public List<HStoreFile> preSelectCompactionForCoprocessor(Collection<HStoreFile> candidates,
    List<HStoreFile> filesCompacting) {
    return getCurrentEligibleFiles(new ArrayList<>(candidates), filesCompacting);
  }
An abstract compaction policy that select files on seq id order.
hbase-server/src/main/java/org/apache/hadoop/hbase/regionserver/compactions/SortedCompactionPolicy.java