@Override public boolean equals(final Object o) {
    if (this == o) {
      return true;
    }
    if (o == null || getClass() != o.getClass()) {
      return false;
    }
    if (!super.equals(o)) {
      return false;
    }
    final AvroParseSpec that = (AvroParseSpec) o;
    return Objects.equals(flattenSpec, that.flattenSpec);
  }
This class is copied from druid source code
in order to avoid adding additional dependencies on druid-indexing-service.
druid-handler/src/java/org/apache/hadoop/hive/druid/json/AvroParseSpec.java