### Question:
OpenIBANValidationClient extends RestGatewaySupport implements IBANValidationClient { @Override public IBANValidationResult validate(String iban) { return getRestTemplate().getForObject(URL_TEMPLATE, IBANValidationResult.class, iban); }  @Override IBANValidationResult validate(String iban);  }### Answer:
@Test public void validIban() { mockRestServiceServer .expect(requestTo("https: .andRespond(withSuccess(new ClassPathResource("NL87TRIO0396451440-result.json"), MediaType.APPLICATION_JSON)); IBANValidationResult result = client.validate("NL87TRIO0396451440"); assertTrue(result.isValid()); }
@Test public void invalidIban() { mockRestServiceServer .expect(requestTo("https: .andRespond(withSuccess(new ClassPathResource("NL28XXXX389242218-result.json"), MediaType.APPLICATION_JSON)); IBANValidationResult result = client.validate("NL28XXXX389242218"); assertFalse(result.isValid()); }