code: public static boolean containsPartitionAvgRecordSize(State state, KafkaPartition partition) {
      return state.contains(
          getPartitionPropName(partition.getTopicName(), partition.getId()) + "." + KafkaSource.AVG_RECORD_SIZE);
    }
docs: Determines whether the given {@link State} contains "[topicname].[partitionid].avg.record.size".