Hi, I have the following case classes:
case class Event(instantValues: InstantValues) case class InstantValues(speed: Int, altitude: Int, time: DateTime) in a DataStream[Event] I'd like to perform a maxBy operation on the field time of instantValue for each event and according to the docs here <https://ci.apache.org/projects/flink/flink-docs-release-1.3/api/java/org/apache/flink/streaming/api/datastream/KeyedStream.html#maxBy-int->it would be possible to use the dot notation such the following: val events = stream .keyBy("otherField") .window(TumblingEventTimeWindows.of(Time.seconds(5))) .maxBy("instantValues.time") positionToMaxBy - In case of a POJO, Scala case class, or Tuple type, the name of the public) field on which to perform the aggregation. Additionally, a dot can be used to drill down into nested objects, as in "field1.fieldxy" . Furthermore "*" can be specified in case of a basic type (which is considered as having only one field). Still, I'm getting the following error: Fields 'instantValues.time' are not valid for 'package.Event(instantValues: package.InstantValues(speed: Integer, altitude: Integer, time: GenericType<org.joda.time.DateTime>))' whereas if, for instance, use only "instantValues" (while implementing its compareTo method) the aggregation works as usual. Any idea as to why this isn't working? Am I doing something wrong? Thanks a lot, Federico
