public function doctorToArray(Doctor $doctor)
 {
     $arr = array('id' => $doctor->getId(), 'name' => "{$doctor->getFirstName()} {$doctor->getMiddleName()} {$doctor->getLastName()}", 'medicalCenters' => array());
     foreach ($doctor->getMedicalCenters() as $dmc) {
         $arr['medicalCenters'][$dmc->getId()] = $dmc->getName();
     }
     return $arr;
 }
 static function getFullName(Doctor $doctor)
 {
     $name = 'Dr. ' . ucwords($doctor->getFirstName()) . ' ';
     if ($doctor->getMiddleName()) {
         $name .= ucfirst(substr($doctor->getMiddleName(), 0, 1)) . '. ';
     }
     $name .= ucwords($doctor->getLastName());
     if ($doctor->getSuffix()) {
         $name .= ' ' . $doctor->getSuffix();
     }
     return $name;
 }