code: private Set<RelationshipTuple> getRels(String relsDatastreamName) {
          List<Datastream> relsDatastreamVersions = m_datastreams.get(relsDatastreamName);
  
          if (relsDatastreamVersions == null || relsDatastreamVersions.size() == 0) {
              return new HashSet<RelationshipTuple>();
          }
  
          Datastream latestRels = relsDatastreamVersions.get(0);
  
          for (Datastream v : relsDatastreamVersions) {
             	if (v.DSCreateDT == null){
             		latestRels = v;
             		break;
             	}
              if (v.DSCreateDT.getTime() > latestRels.DSCreateDT.getTime()) {
                  latestRels = v;
              }
          }
  
          try {
              return RDFRelationshipReader.readRelationships(latestRels);
          } catch (ServerException e) {
              throw new RuntimeException("Error reading object relationships in " + relsDatastreamName, e);
          }
      }
docs: Given a relationships datastream name, return the relationships contained
  in that datastream