@Override
  public boolean equals(Object o) {
    if (this == o) {
      return true;
    }
    if (o == null || getClass() != o.getClass()) {
      return false;
    }
    KafkaStateCheckpointMarker that = (KafkaStateCheckpointMarker) o;
    return Objects.equals(changelogSSP, that.changelogSSP) &&
        Objects.equals(changelogOffset, that.changelogOffset);
  }
Builds a map of store changelog SSPs to their offset for Kafka changelog backed stores from the provided
map of state backend factory name to map of store name to serialized state checkpoint markers.

@param stateBackendToStoreSCMs Map of state backend factory name to map of store name to serialized
                               state checkpoint markers
@return Map of store changelog SSPss to their optional offset, or an empty map if there is no mapping for
{@link #KAFKA_STATE_BACKEND_FACTORY_NAME} in the input map. Optional offset may be empty if the
changelog SSP was empty.
samza-core/src/main/java/org/apache/samza/checkpoint/kafka/KafkaStateCheckpointMarker.java