/** * Get the associated Professor object * * @param PropelPDO Optional Connection object. * @return Professor The associated Professor object. * @throws PropelException */ public function getProfessor(PropelPDO $con = null) { if ($this->aProfessor === null && $this->professor_id !== null) { $this->aProfessor = ProfessorPeer::retrieveByPk($this->professor_id); /* The following can be used additionally to guarantee the related object contains a reference to this object. This level of coupling may, however, be undesirable since it could result in an only partially populated collection in the referenced object. $this->aProfessor->addGradeunits($this); */ } return $this->aProfessor; }