/**
  * Retrieve the resource by its identifier
  *
  * @param theId The resource identity
  * @return The resource
  */
 @Search()
 public List<Patient> getResourceById(@RequiredParam(name = "_id") TokenOrListParam theIds) {
   List<Patient> patients = new ArrayList<Patient>();
   for (BaseCodingDt id : theIds.getListAsCodings()) {
     Patient patient = getIdToPatient().get(id.getCodeElement().getValue());
     if (patient != null) {
       patients.add(patient);
     }
   }
   return patients;
 }