《二十：消费者端统计加工消息》

自定义拦截器实现ProducerInterceptor

package com.wangbiao.kafka.interceptor;

import org.apache.kafka.clients.producer.ProducerInterceptor;
import org.apache.kafka.clients.producer.ProducerRecord;
import org.apache.kafka.clients.producer.RecordMetadata;

import java.util.Map;

/**
 * 拦截改造消费的消息   记录改造value用竖线分割（下游自行解析）
 */
public class TimeInterceptor implements ProducerInterceptor<String,String> {
    @Override
    public ProducerRecord<String, String> onSend(ProducerRecord<String, String> record) {
        String value = record.value();
        //记录改造value用竖线分割
        return new ProducerRecord(record.topic(),record.partition(),record.key(),System.currentTimeMillis()+"|"+value);
    }

    @Override
    public void onAcknowledgement(RecordMetadata metadata, Exception exception) {

    }

    @Override
    public void close() {

    }

    @Override
    public void configure(Map<String, ?> configs) {

    }
}

统计消费了多少数据

package com.wangbiao.kafka.interceptor;

import org.apache.kafka.clients.producer.ProducerInterceptor;
import org.apache.kafka.clients.producer.ProducerRecord;
import org.apache.kafka.clients.producer.RecordMetadata;

import java.util.Map;

/**
 * 统计拦截多少失败多少数据
 */
public class CounterInterceptor implements ProducerInterceptor {
    public int success;
    public int error;
    @Override
    public ProducerRecord onSend(ProducerRecord record) {
        return record;
    }

    @Override
    public void onAcknowledgement(RecordMetadata metadata, Exception exception) {
               if (metadata!=null){
                   if(success==Integer.MAX_VALUE){ success=0; success++; }
                   success++;
               }else {
                   if(error==Integer.MAX_VALUE){error=0; error++; }
                   error++;
               }
    }

    @Override
    public void close() {
        System.out.println("success:"+success);
        System.out.println("error:"+error);
    }

    @Override
    public void configure(Map<String, ?> configs) {

    }
}