code: private void processPredecessor(Task task, MapRow row)
     {
        Task predecessor = m_taskMap.get(row.getUUID("PREDECESSOR_UUID"));
        if (predecessor != null)
        {
           task.addPredecessor(predecessor, row.getRelationType("RELATION_TYPE"), row.getDuration("LAG"));
        }
     }
docs: Extract data for a single predecessor.
  
  @param task parent task
  @param row Synchro predecessor data