使用EmbeddedKafka进行单元测试

Properties props = new Properties();
props.put("listeners", "PLAINTEXT://localhost:9093");
props.put("advertised.listeners", "PLAINTEXT://localhost:9093");
props.put("log.dirs", "/tmp/kafka-logs");
KafkaServer kafkaServer = new KafkaServer(new KafkaConfig(props));
kafkaServer.startup();

Properties producerProps = new Properties();
producerProps.put("bootstrap.servers", "localhost:9093");
producerProps.put("key.serializer", "org.apache.kafka.common.serialization.StringSerializer");
producerProps.put("value.serializer", "org.apache.kafka.common.serialization.StringSerializer");

Producer<String, String> producer = new KafkaProducer<>(producerProps);
producer.send(new ProducerRecord<>("test-topic", "key", "value"));
producer.close();

Properties consumerProps = new Properties();
consumerProps.put("bootstrap.servers", "localhost:9093");
consumerProps.put("group.id", "test-group");
consumerProps.put("key.deserializer", "org.apache.kafka.common.serialization.StringDeserializer");
consumerProps.put("value.deserializer", "org.apache.kafka.common.serialization.StringDeserializer");

KafkaConsumer<String, String> consumer = new KafkaConsumer<>(consumerProps);
consumer.subscribe(Arrays.asList("test-topic"));

while (true) {
    ConsumerRecords<String, String> records = consumer.poll(Duration.ofMillis(100));
    for (ConsumerRecord<String, String> record : records) {
        System.out.printf("offset = %d, key = %s, value = %s%n", record.offset(), record.key(), record.value());
    }
}