@Test
 public void testToHL7WithNoDate() {
   assertNull(transformer.toHL7(new PatientInfo()));
 }
 @Test
 public void testToHL7() {
   PatientInfo patientInfo = new PatientInfo();
   patientInfo.setDateOfBirth("19800102030405+0100");
   assertEquals("19800102", transformer.toHL7(patientInfo).get(0));
 }