批量消费器使用Apache Camel集成Kafka进行数据的消费。
代码示例:
public class KafkaBatchConsumerRoute extends RouteBuilder {
private final int batchSize = 100;
private final String brokers = "localhost:9092";
private final String topic = "test-topic";
@Override
public void configure() throws Exception {
KafkaComponent kafka = new KafkaComponent();
Properties props = new Properties();
props.put("bootstrap.servers", brokers);
props.put("group.id", "test-group");
kafka.setConfiguration(props);
getContext().addComponent("kafka", kafka);
// Consume messages in batches of batchSize
from("kafka:" + topic + "?groupId=test-group&autoOffsetReset=earliest&maxPollRecords=" + batchSize)
.split(body(), new BatchAggregationStrategy())
.log("${body}")
.to("file:/path/to/output");
}
private class BatchAggregationStrategy implements AggregationStrategy {
@Override
public Exchange aggregate(Exchange oldExchange, Exchange newExchange) {
List messages = null;
if (oldExchange == null) {
messages = new ArrayList<>();
messages.add(newExchange.getIn());
newExchange.getIn().setBody(messages);
return newExchange;
} else {
messages = oldExchange.getIn().getBody(List.class);
messages.add(newExchange.getIn());
return oldExchange;
}
}
}
}