java kafka与storm如何集成

要将Java Kafka与Apache Storm集成，您需要遵循以下步骤：

1. 添加依赖项

首先，确保在您的项目中添加了Kafka和Storm的依赖项。对于Maven项目，您可以在pom.xml文件中添加以下依赖项：

<!-- Kafka -->
<dependency>
    <groupId>org.apache.kafka</groupId>
    <artifactId>kafka-clients</artifactId>
    <version>2.8.0</version>
</dependency>

<!-- Storm -->
<dependency>
    <groupId>org.apache.storm</groupId>
    <artifactId>storm-core</artifactId>
    <version>2.3.2</version>
</dependency>

2. 创建Kafka生产者

创建一个Java类，用于向Kafka主题发送消息。例如，创建一个名为KafkaProducer.java的文件：

import org.apache.kafka.clients.producer.KafkaProducer;
import org.apache.kafka.clients.producer.ProducerRecord;

import java.util.Properties;

public class KafkaProducer {
    public static void main(String[] args) {
        Properties props = new Properties();
        props.put("bootstrap.servers", "localhost:9092");
        props.put("key.serializer", "org.apache.kafka.common.serialization.StringSerializer");
        props.put("value.serializer", "org.apache.kafka.common.serialization.StringSerializer");

        KafkaProducer<String, String> producer = new KafkaProducer<>(props);
        for (int i = 0; i < 100; i++) {
            producer.send(new ProducerRecord<>("my-topic", Integer.toString(i), Integer.toString(i * 2)));
        }

        producer.close();
    }
}

3. 创建Storm Topology

创建一个Java类，用于定义Storm Topology。例如，创建一个名为KafkaSpout.java的文件：

import org.apache.storm.topology.TopologyBuilder;
import org.apache.storm.StormSubmitter;

public class KafkaSpout {
    public static void main(String[] args) throws Exception {
        TopologyBuilder builder = new TopologyBuilder();
        builder.setSpout("kafka-spout", new KafkaSpout(), 5);
        builder.setBolt("bolt", new KafkaBolt(), 5).shuffleGrouping("kafka-spout");

        Config config = new Config();
        config.setNumWorkers(3);

        StormSubmitter.submitTopology("kafka-topology", config, builder.createTopology());
    }
}

4. 创建Kafka Spout

创建一个Java类，用于从Kafka主题读取消息。例如，创建一个名为KafkaSpout.java的文件：

import org.apache.storm.kafka.spout.KafkaSpoutConfig;
import org.apache.storm.topology.TopologyBuilder;

public class KafkaSpout {
    public static void main(String[] args) throws Exception {
        TopologyBuilder builder = new TopologyBuilder();
        builder.setSpout("kafka-spout", new KafkaSpoutConfig
                .Builder("localhost:9092", "my-topic")
                .setProp("key.deserializer", "org.apache.kafka.common.serialization.StringDeserializer")
                .setProp("value.deserializer", "org.apache.kafka.common.serialization.StringDeserializer")
                .build(), 5);
        builder.setBolt("bolt", new KafkaBolt(), 5).shuffleGrouping("kafka-spout");

        Config config = new Config();
        config.setNumWorkers(3);

        StormSubmitter.submitTopology("kafka-topology", config, builder.createTopology());
    }
}

5. 创建Kafka Bolt

创建一个Java类，用于处理从Kafka Spout接收到的消息。例如，创建一个名为KafkaBolt.java的文件：

import org.apache.storm.topology.BasicOutputCollector;
import org.apache.storm.topology.OutputFieldsDeclarer;
import org.apache.storm.topology.base.BaseBasicBolt;
import org.apache.storm.tuple.Tuple;

public class KafkaBolt extends BaseBasicBolt {
    @Override
    public void execute(Tuple input, BasicOutputCollector collector) {
        String message = input.getStringByField("value");
        System.out.println("Received message: " + message);
    }

    @Override
    public void declareOutputFields(OutputFieldsDeclarer declarer) {
    }
}

现在，您已经成功地将Java Kafka与Apache Storm集成在一起。运行KafkaProducer.java以发送消息到Kafka主题，然后运行KafkaSpout.java以从Kafka主题读取消息并将其传递给KafkaBolt.java进行处理。