public static Set<SystemStream> getSystemStreams(JobModel jobModel) {
    Map<TaskName, Set<SystemStreamPartition>> taskToSSPs = getTaskToSystemStreamPartitions(jobModel);
    return taskToSSPs.values().stream().flatMap(taskSSPs -> taskSSPs.stream().map(ssp -> ssp.getSystemStream())).collect(Collectors.toSet());
  }
Compares the {@link ContainerModel}s across the two {@link JobModel}s.
@param first first job model
@param second second job model
@return true - if {@link ContainerModel}s are the same across {@link JobModel}s
        false - otherwise
samza-core/src/main/java/org/apache/samza/job/model/JobModelUtil.java