### Question:
HubFirmwareURLBuilder implements FirmwareURLBuilder<Hub> { @Override public String buildURL(Hub object, String firmwareTarget) { Preconditions.checkNotNull(object, "The hub must not be null."); Preconditions.checkNotNull(firmwareTarget, "The version must not be null."); return new StringBuilder() .append(firmwareDownloadScheme) .append(": .append(firmwareDownloadHost) .append("/") .append(firmwareTarget) .append(EXTENSION) .toString(); }  @Override String buildURL(Hub object, String firmwareTarget);  }### Answer:
@Test public void testFirmwareURLBuild() { Hub hub = new Hub(); assertEquals("https: }