class PartitionGroup {

    void setPartitionTime(final TopicPartition partition, final long partitionTime) {
        final RecordQueue queue = partitionQueues.get(partition);
        if (queue == null) {
            throw new IllegalStateException("Partition " + partition + " not found.");
        }
        if (streamTime < partitionTime) {
            streamTime = partitionTime;
        }
        queue.setPartitionTime(partitionTime);
    }

      PartitionGroup(final Map<TopicPartition, RecordQueue> partitionQueues, final Sensor recordLatenessSensor);

}