### Question:
TppDataUploaderController implements TppDataUploaderRestApi { @Override public ResponseEntity<String> generateIban(String tppId) { return ResponseEntity.ok(ibanGenerationService.generateNextIban(tppId)); }  @Override ResponseEntity<String> uploadData(MultipartFile file); @Override ResponseEntity<Resource> generateData(boolean generatePayments, String currency); @Override ResponseEntity<String> generateIban(String tppId); @Override ResponseEntity<Map<String, String>> uploadTransactions(MultipartFile file); @Override ResponseEntity<Resource> downloadTransactionTemplate();  }### Answer:
@Test void generateIban() { when(ibanGenerationService.generateNextIban(TPP_ID)).thenReturn(USER_IBAN); ResponseEntity<String> response = uploaderController.generateIban(TPP_ID); assertTrue(response.getStatusCode().is2xxSuccessful()); assertFalse(response.getBody().isEmpty()); }