private HRegion initHRegion(String callingMethod, Configuration conf) throws IOException {
    TableDescriptorBuilder builder = TableDescriptorBuilder.newBuilder(TABLENAME);
    for (byte[] family : FAMILIES) {
      builder.setColumnFamily(ColumnFamilyDescriptorBuilder.of(family));
    }
    RegionInfo info = RegionInfoBuilder.newBuilder(TABLENAME).build();
    Path path = new Path(DIR, callingMethod);
    return HBaseTestingUtil.createRegionAndWAL(info, path, conf, builder.build());
  }
This test verifies the correctness of the Per Column Family flushing strategy
hbase-server/src/test/java/org/apache/hadoop/hbase/regionserver/TestPerColumnFamilyFlush.java