public static Properties getConfig(final String broker,
                                           final String application,
                                           final String id,
                                           final String processingGuarantee,
                                           final String stateDir) {
            final Properties properties =
                mkProperties(
                    mkMap(
                        mkEntry(StreamsConfig.BOOTSTRAP_SERVERS_CONFIG, broker),
                        mkEntry(StreamsConfig.APPLICATION_ID_CONFIG, application),
                        mkEntry(StreamsConfig.CLIENT_ID_CONFIG, id),
                        mkEntry(StreamsConfig.PROCESSING_GUARANTEE_CONFIG, processingGuarantee),
                        mkEntry(ConsumerConfig.AUTO_OFFSET_RESET_CONFIG, "earliest"),
                        mkEntry(StreamsConfig.STATE_DIR_CONFIG, stateDir)
                    )
                );
            properties.put(StreamsConfig.COMMIT_INTERVAL_MS_CONFIG, 1000L);
            return properties;
        }
Generates a keySpace number of unique keys normally distributed,
with the mean at 0 and stdDev 1/3 of the way through the keySpace
any sample more than 3 standard deviations from the mean are assigned to the 0 key.
<p>
This is designed to roughly balance the key properties of two dominant real-world
data distribution: Zipfian and Normal, while also being efficient to generate.
streams/src/test/java/org/apache/kafka/streams/tests/RelationalSmokeTest.java