Kafka Client is a vanilla java library that makes it easy to consume data from kafka, a list of features:
- Parallel consuming
- Consuming retry
- Consuming failover
- Designed to be easy to mock and test
- Designed to support slow consumers without kafka rebalancing
- Designed to high throughput usage
- Individual record consuming
- Batch records consuming
- Frameworkless, but easily configurable to some when wanted
- Commits managed for you based on behavior
- Low CPU usage
compile("com.mageddo.rapids-kafka-client:rapids-kafka-client:2.0.6")ConsumerConfig.<String, String>builder() .prop(KEY_DESERIALIZER_CLASS_CONFIG, StringDeserializer.class.getName()) .prop(VALUE_DESERIALIZER_CLASS_CONFIG, StringDeserializer.class.getName()) .prop(GROUP_ID_CONFIG, "stocks") .topics("stock_changed") .recoverCallback(ctx -> { // here you can send the message to another topic, send a SMS, etc. log.info("status=recovering, value={}", ctx.record().value()); }) .callback((ctx, record) -> { log.info("status=consumed, value={}", record.value()); }) .build() .consume() .waitFor();public static void main(String[] args) { final ConsumerStarter consumerStarter = ConsumerStarter.start(defaultConfig(), Arrays.asList( new StockConsumer() // and many other consumers )); consumerStarter.waitFor(); // consumerStarter.stop(); } static ConsumerConfig defaultConfig() { return ConsumerConfig.builder() .prop(CommonClientConfigs.BOOTSTRAP_SERVERS_CONFIG, "localhost:9092") .prop(KEY_DESERIALIZER_CLASS_CONFIG, StringDeserializer.class.getName()) .prop(VALUE_DESERIALIZER_CLASS_CONFIG, StringDeserializer.class.getName()) .prop(GROUP_ID_CONFIG, "my-group-id") .build(); } static class StockConsumer implements Consumer { ConsumeCallback<String, String> consume() { return (callbackContext, record) -> { System.out.printf("message from kafka: %s\n", record.value()); }; } @Override public ConsumerConfig<String, String> config() { return ConsumerConfig .<String, String>builder() .topics("stocks_events") .consumers(1) .callback(this.consume()) .build(); } }