@ParameterizedTest
    @ValueSource(booleans = {true, false})
    public void testInner(final boolean cacheEnabled) {
        final StreamsBuilder builder = new StreamsBuilder();
        final KStream<Long, String> leftStream = builder.stream(INPUT_TOPIC_LEFT);
        final KTable<Long, String> rightTable = builder.table(INPUT_TOPIC_RIGHT);
        final Properties streamsConfig = setupConfigsAndUtils(cacheEnabled);
        streamsConfig.put(StreamsConfig.APPLICATION_ID_CONFIG, APP_ID + "-inner");
        leftStream.join(rightTable, valueJoiner).to(OUTPUT_TOPIC);

        final List<List<TestRecord<Long, String>>> expectedResult = Arrays.asList(
            null,
            null,
            null,
            null,
            Collections.singletonList(new TestRecord<>(ANY_UNIQUE_KEY, "B-a", null, 5L)),
            null,
            null,
            null,
            null,
            null,
            null,
            null,
            null,
            null,
            Collections.singletonList(new TestRecord<>(ANY_UNIQUE_KEY, "D-d", null,  6L)),
            null,
            null,
            null,
            Collections.singletonList(new TestRecord<>(ANY_UNIQUE_KEY, "E-e", null,  15L)),
            null,
            null,
            null,
            null
        );

        runTestWithDriver(input, expectedResult, streamsConfig, builder.build(streamsConfig));
    }
Tests all available joins of Kafka Streams DSL.
streams/src/test/java/org/apache/kafka/streams/integration/StreamTableJoinIntegrationTest.java