code: private boolean removeRelation(List<Relation> relationList, Task targetTask, RelationType type, Duration lag)
     {
        boolean matchFound = false;
        for (Relation relation : relationList)
        {
           if (relation.getTargetTask() == targetTask)
           {
              if (relation.getType() == type && relation.getLag().compareTo(lag) == 0)
              {
                 matchFound = relationList.remove(relation);
                 break;
              }
           }
        }
        return matchFound;
     }
docs: Internal method used to locate an remove an item from a list Relations.
  
  @param relationList list of Relation instances
  @param targetTask target relationship task
  @param type target relationship type
  @param lag target relationship lag
  @return true if a relationship was removed