发布于 2017-12-02 00:24:56 | 231 次阅读 | 评论: 0 | 来源: 网友投递
Apache Kafka 开源消息系统
Apache Kafka是一个开源消息系统项目,由Scala写成。该项目的目标是为处理实时数据提供一个统一、高通量、低等待的平台。
Spring for Apache Kafka 2.1.0 已发布,同时发布的还有 1.3.2 和 2.0.2 维护版本,包含重要的 Bug 修复。
2.1.0 版本的主要将 kafka-clients 库升级到 1.0.0,以及一些改进:
Sometimes, when a message can’t be processed, you may wish to stop the container so the condition can be corrected and the message re-delivered. The framework now provides the ContainerStoppingErrorHandler
for record listeners and ContainerStoppingBatchErrorHandler
for batch listeners.
The KafkaAdmin
now supports increasing partitions when a NewTopic
bean is detected with a larger number of partitions than currently exist on the topic.
StringJsonMessageConverter
and JsonSerializer/JsonDeserializer
now pass and consume type information in Headers
. This allows multiple types to be easily sent/received on the same topic:
@SpringBootApplication public class Kafka21Application { public static void main(String[] args) { SpringApplication.run(Kafka21Application.class, args) .close(); } @Bean public ApplicationRunner runner(KafkaTemplate<Object, Object> template) { return args -> { template.send(MessageBuilder.withPayload(42) .setHeader(KafkaHeaders.TOPIC, "blog") .build()); template.send(MessageBuilder.withPayload("43") .setHeader(KafkaHeaders.TOPIC, "blog") .build()); Thread.sleep(5_000); }; } @Bean public StringJsonMessageConverter converter() { return new StringJsonMessageConverter(); } @Component @KafkaListener(id = "multi", topics = "blog") public static class Listener { @KafkaHandler public void intListener(Integer in) { System.out.println("Got an int: " + in); } @KafkaHandler public void stringListener(String in) { System.out.println("Got a string: " + in); } } }
Got an int: 42 Got a string: 43
the JsonSerializer
and JsonDeserializer
can be configured using kafka properties for the producer/consumer.