@After
  public void teardown() throws IOException {
    if (region != null) {
      CacheConfig cacheConfig = region.getStores().get(0).getCacheConfig();
      region.close();
      WAL wal = region.getWAL();
      if (wal != null) {
        wal.close();
      }
      cacheConfig.getBlockCache().ifPresent(BlockCache::shutdown);
      region = null;
    }
  }
Testing of HRegion.incrementColumnValue, HRegion.increment, and HRegion.append
hbase-server/src/test/java/org/apache/hadoop/hbase/regionserver/TestAtomicOperation.java