MpiDataSaver { public void saveMpi(Patients patientList) { saveMpi(patientList, defaultMpiFilename); } MpiDataSaver(); void saveMpi(Patients patientList); void saveMpi(Patients patientList, String file); Patients loadMpi(); Patients loadMpi(String file);  }
@Test(expected = MpiException.class) public void testSaveMpi_BadFile() { MpiDataSaver mpiDataSaver = createMpiDataSaver(); mpiDataSaver.saveMpi(null, mockMpiDirectoryName); }