@AfterEach
    public void tearDown() throws IOException {
        if (streams != null) {
            streams.close();
        }
        // Remove any state from previous test runs
        IntegrationTestUtils.purgeLocalStreamsState(streamsConfiguration);
    }
End-to-end integration test based on using regex and named topics for creating sources, using
an embedded Kafka cluster.
streams/src/test/java/org/apache/kafka/streams/integration/RegexSourceIntegrationTest.java