### Question:
ContactsBackend extends ObmSyncBackend<WindowingContact> { @Override public PIMDataType getPIMDataType() { return PIMDataType.CONTACTS; } @Inject @VisibleForTesting  ContactsBackend(MappingService mappingService, 
			BookClient.Factory bookClientFactory, 
			ContactConfiguration contactConfiguration,
			WindowingDao windowingDao,
			ClientIdService clientIdService,
			ContactConverter contactConverter,
			DateService dateService,
			OpushResourcesHolder opushResourcesHolder,
			ContactCreationIdempotenceService creationIdempotenceService,
			FolderSnapshotDao folderSnapshotDao); @Override PIMDataType getPIMDataType(); @Override BackendFolders getBackendFolders(UserDataRequest udr); @Override int getItemEstimateSize(UserDataRequest udr, ItemSyncState state, CollectionId collectionId, 
		SyncCollectionOptions syncCollectionOptions); @Override ServerId createOrUpdate(UserDataRequest udr, CollectionId collectionId,
			ServerId serverId, String clientId, IApplicationData data); @Override void delete(UserDataRequest udr, CollectionId collectionId, ServerId serverId, Boolean moveToTrash); @Override List<ItemChange> fetch(UserDataRequest udr, CollectionId collectionId, List<ServerId> fetchServerIds, SyncCollectionOptions syncCollectionOptions,
				ItemSyncState previousItemSyncState, SyncKey newSyncKey); @Override List<ItemChange> fetch(UserDataRequest udr, CollectionId collectionId, List<ServerId> fetchServerIds, SyncCollectionOptions syncCollectionOptions); @Override ServerId move(UserDataRequest udr, Folder srcFolder, Folder dstFolder,
			ServerId messageId); @Override void emptyFolderContent(UserDataRequest udr, Folder folder,
			boolean deleteSubFolder); @Override void initialize(DeviceId deviceId, CollectionId collectionId, FilterType filterType, SyncKey newSyncKey); @Override BackendId createFolder(UserDataRequest udr, FolderCreateRequest folderCreateRequest,
			Optional<BackendId> backendId);  }### Answer:
@Test public void testGetPIMDataType() { ContactsBackend contactsBackend = new ContactsBackend(null, null, null, null, null, null, null, null, null, null); assertThat(contactsBackend.getPIMDataType()).isEqualTo(PIMDataType.CONTACTS); }