### Question:
ProductModuleService { public static Page<ProductModule> list(final Context context, final String filter) throws NetLicensingException { final Map<String, Object> params = new HashMap<String, Object>(); if (StringUtils.isNotBlank(filter)) { params.put(Constants.FILTER, filter); } return NetLicensingService.getInstance().list(context, Constants.ProductModule.ENDPOINT_PATH, params, ProductModule.class); }  static ProductModule create(final Context context, final String productNumber,
            final ProductModule productModule); static ProductModule get(final Context context, final String number); static Page<ProductModule> list(final Context context, final String filter); static ProductModule update(final Context context, final String number, final ProductModule productModule); static void delete(final Context context, final String number, final boolean forceCascade);  }### Answer:
@Test public void testList() throws Exception { final Page<ProductModule> productModules = ProductModuleService.list(context, null); assertNotNull(productModules); assertTrue(productModules.hasContent()); assertEquals(3, productModules.getItemsNumber()); assertEquals("PM001-TEST", productModules.getContent().get(0).getNumber()); assertEquals("Test module 2", productModules.getContent().get(1).getName()); assertEquals(Constants.LicensingModel.Subscription.NAME, productModules.getContent().get(2).getLicensingModel()); }