### Question:
BufferedBulkOperations implements BatchOperations<Bulk> { protected ObjectWriter configuredWriter() { ObjectMapper objectMapper = new ExtendedObjectMapper(new JsonFactory()) .setSerializationInclusion(JsonInclude.Include.NON_EMPTY) .configure(SerializationFeature.CLOSE_CLOSEABLE, false) .addMixIn(BufferedIndex.class, BulkableActionMixIn.class); for (JacksonMixIn mixIn: mixIns) { objectMapper.addMixIn(mixIn.getTargetClass(), mixIn.getMixInClass()); } return objectMapper.writerFor(BufferedIndex.class); } BufferedBulkOperations(PooledItemSourceFactory pooledItemSourceFactory);  BufferedBulkOperations(PooledItemSourceFactory pooledItemSourceFactory, JacksonMixIn[] mixIns, String mappingType); @Override Object createBatchItem(String indexName, Object source); @Override Object createBatchItem(String indexName, ItemSource source); @Override BatchBuilder<Bulk> createBatchBuilder(); static final String DEFAULT_MAPPING_TYPE; }### Answer:
@Test public void createsConfiguredWriter() { PooledItemSourceFactory bufferedSourceFactory = PooledItemSourceFactoryTest.createDefaultTestSourceFactoryConfig().build(); BufferedBulkOperations bufferedBulkOperations = new BufferedBulkOperations(bufferedSourceFactory); ObjectWriter writer = bufferedBulkOperations.configuredWriter(); Assert.assertNotNull(writer); }