### Question:
KafkaTableSourceSinkFactoryBase implements
		StreamTableSourceFactory<Row>,
		StreamTableSinkFactory<Row> { @Override public StreamTableSink<Row> createStreamTableSink(Map<String, String> properties) { final DescriptorProperties descriptorProperties = getValidatedProperties(properties); final TableSchema schema = descriptorProperties.getTableSchema(SCHEMA()); final String topic = descriptorProperties.getString(CONNECTOR_TOPIC); final Optional<String> proctime = SchemaValidator.deriveProctimeAttribute(descriptorProperties); final List<RowtimeAttributeDescriptor> rowtimeAttributeDescriptors = SchemaValidator.deriveRowtimeAttributes(descriptorProperties); if (proctime.isPresent() || !rowtimeAttributeDescriptors.isEmpty() || checkForCustomFieldMapping(descriptorProperties, schema)) { throw new TableException("Time attributes and custom field mappings are not supported yet."); } return createKafkaTableSink( schema, topic, getKafkaProperties(descriptorProperties), getFlinkKafkaPartitioner(descriptorProperties), getSerializationSchema(properties)); }  @Override Map<String, String> requiredContext(); @Override List<String> supportedProperties(); @Override StreamTableSource<Row> createStreamTableSource(Map<String, String> properties); @Override StreamTableSink<Row> createStreamTableSink(Map<String, String> properties);  }### Answer:
@Test public void testTableSink() { final TableSchema schema = TableSchema.builder() .field(FRUIT_NAME, Types.STRING()) .field(COUNT, Types.DECIMAL()) .field(EVENT_TIME, Types.SQL_TIMESTAMP()) .build(); final KafkaTableSinkBase expected = getExpectedKafkaTableSink( schema, TOPIC, KAFKA_PROPERTIES, Optional.of(new FlinkFixedPartitioner<>()), new TestSerializationSchema(schema.toRowType())); final TestTableDescriptor testDesc = new TestTableDescriptor( new Kafka() .version(getKafkaVersion()) .topic(TOPIC) .properties(KAFKA_PROPERTIES) .sinkPartitionerFixed() .startFromSpecificOffsets(OFFSETS)) .withFormat(new TestTableFormat()) .withSchema( new Schema() .field(FRUIT_NAME, Types.STRING()) .field(COUNT, Types.DECIMAL()) .field(EVENT_TIME, Types.SQL_TIMESTAMP())) .inAppendMode(); final Map<String, String> propertiesMap = testDesc.toProperties(); final TableSink<?> actualSink = TableFactoryService.find(StreamTableSinkFactory.class, propertiesMap) .createStreamTableSink(propertiesMap); assertEquals(expected, actualSink); final KafkaTableSinkBase actualKafkaSink = (KafkaTableSinkBase) actualSink; final DataStreamMock streamMock = new DataStreamMock(new StreamExecutionEnvironmentMock(), schema.toRowType()); actualKafkaSink.emitDataStream(streamMock); assertTrue(getExpectedFlinkKafkaProducer().isAssignableFrom(streamMock.sinkFunction.getClass())); }