public static JsonSerialization<IOStatisticsSnapshot> serializer() {
    return new JsonSerialization<>(IOStatisticsSnapshot.class, false, true);
  }
@Test
  public void testJsonRoundTrip() throws Throwable {
    JsonSerialization<IOStatisticsSnapshot> serializer
        = IOStatisticsSnapshot.serializer();

    String json = serializer.toJson(snapshot);
    LOG.info("serialized form\n{}", json);
    IOStatisticsSnapshot deser = serializer.fromJson(json);
    verifyDeserializedInstance(deser);
  }