6.2 Kafka Stream 数据清洗

需求

实时处理单词带有>>>前缀的内容。例如输入 atguigu>>>ximenqing，最终处理成 ximenqing

需求分析

实例操作

1. 添加依赖

<!-- https://mvnrepository.com/artifact/org.apache.kafka/kafka-streams -->
<dependency>
    <groupId>org.apache.kafka</groupId>
    <artifactId>kafka-streams</artifactId>
    <version>0.11.0.3</version>
</dependency>

2. 代码

主类

package com.atguigu.kafka.stream;

import org.apache.kafka.streams.KafkaStreams;
import org.apache.kafka.streams.StreamsConfig;
import org.apache.kafka.streams.processor.Processor;
import org.apache.kafka.streams.processor.ProcessorSupplier;
import org.apache.kafka.streams.processor.TopologyBuilder;

import java.util.Properties;

public class MyStream {
    public static void main(String[] args) {
        final String sourceTopic = "first";
        final String sinkTopic = "second";
        // 1. 设置参数
        Properties props = new Properties();
        props.put(StreamsConfig.APPLICATION_ID_CONFIG, "mystreams");
        props.put(StreamsConfig.BOOTSTRAP_SERVERS_CONFIG, "hadoop201:9092");
        // 2. 创建拓扑结构builder对象
        TopologyBuilder builder = new TopologyBuilder()
                .addSource("source", "first")
                .addProcessor("processor", new MySupplier(), "source")
                .addSink("sink", "second", "processor");

        KafkaStreams streams = new KafkaStreams(builder, props);
        // 3. 启动 kafka steams
        streams.start();
    }
}

具体业处理

package com.atguigu.kafka.stream;

import org.apache.kafka.streams.processor.Processor;
import org.apache.kafka.streams.processor.ProcessorContext;
import org.apache.kafka.streams.processor.ProcessorSupplier;

public class MySupplier implements ProcessorSupplier<byte[], byte[]> {
    @Override
    public Processor<byte[], byte[]> get() {
        return new MyProcessor();
    }

    private class MyProcessor implements Processor<byte[], byte[]> {

        private ProcessorContext context;

        @Override
        public void init(ProcessorContext context) {
            this.context = context;
        }

        @Override
        public void process(byte[] key, byte[] value) {
            byte[] newValue = new String(value).replace(">>>", "").getBytes();
            context.forward(key, newValue);
        }

        @Override
        public void punctuate(long l) {

        }

        @Override
        public void close() {

        }
    }
}

3. 测试

a:运行主程序

b:开启生成者向 topic first 写入数据

kafka-console-producer.sh --broker-list hadoop201:9092 --topic first

c: 开启消费者从 topic second 消费数据

kafka-console-consumer.sh --zookeeper hadoop201:2181  --topic second

d: 开始写入数据, 并观察消费消费的数据

写入的数据:

消费到的数据: