Iterator iterator = this.getAssignmentsReceived(null, null).iterator();
Iterator iterator = this.getAssignmentsReceived(null, null, null).iterator();
  private Collection getGrantableAssignments(Subsystem subsystem)      throws ObjectNotFoundException  {    Collection assignments = new HashSet();    Iterator iterator = this.getAssignmentsReceived(null, null).iterator();    while (iterator.hasNext())    {      Assignment assignment = (Assignment) (iterator.next());      if (assignment.isGrantable()          && assignment.getFunction().getSubsystem().equals(subsystem))      {        assignments.add(assignment);      }    }    return assignments;  }