Kafaka stream countdownlatch的方法替代了while true循环

Pipe.java

public class Pipe {
    public static void main(String[] args) {
        Properties props = new Properties();
        props.put(StreamsConfig.APPLICATION_ID_CONFIG, "streams-pipe");
        props.put(StreamsConfig.BOOTSTRAP_SERVERS_CONFIG, "localhost:9092");
        props.put(StreamsConfig.DEFAULT_KEY_SERDE_CLASS_CONFIG, Serdes.String().getClass());
        props.put(StreamsConfig.DEFAULT_VALUE_SERDE_CLASS_CONFIG, Serdes.String().getClass());

        StreamsBuilder builder = new StreamsBuilder();
        builder.stream("streams-plaintext-input").to("streams-pipe-output");
        Topology topology = builder.build();


        KafkaStreams kafkaStreams = new KafkaStreams(topology, props);
        CountDownLatch countDownLatch = new CountDownLatch(1);
        Runtime.getRuntime().addShutdownHook(new Thread("streams-shutdown-hook") {
            @Override
            public void run() {
                kafkaStreams.close();
                countDownLatch.countDown();
            }
        });

        kafkaStreams.start();
        try {
            countDownLatch.await();
        } catch (InterruptedException e) {
            System.exit(1);
        }
        System.exit(0);
    }
}