Sink-kafkaSink的使用

上篇：Sink-writeToSocke的使用

若想要实现实现Exactly Once，kafka必须要0.11以上版本（可以支持事务）

直接代码

package cn._51doit.flink.day01;

import org.apache.flink.api.common.functions.RuntimeContext;
import org.apache.flink.api.common.serialization.SimpleStringSchema;
import org.apache.flink.configuration.Configuration;
import org.apache.flink.streaming.api.datastream.DataStreamSource;
import org.apache.flink.streaming.api.environment.StreamExecutionEnvironment;
import org.apache.flink.streaming.api.functions.sink.RichSinkFunction;
import org.apache.flink.streaming.connectors.kafka.FlinkKafkaProducer;
public class KafkaSinkDemo {
    public static void main(String[] args) throws Exception {
        //local模式默认的并行度是当前节点逻辑核的数量
        Configuration configuration = new Configuration();
        StreamExecutionEnvironment env = StreamExecutionEnvironment.createLocalEnvironmentWithWebUI(configuration);

        //DataStream的并行度
        int parallelism01 = env.getParallelism();
        System.out.println("执行环境默认的并行度是："+parallelism01);

        DataStreamSource lines = env.socketTextStream("192.168.242.102", 9999);

        //获取DataStream的并行度
        int parallelism = lines.getParallelism();
        System.out.println("SocketSink的并行度："+parallelism);

        //FlinkKafkaProducer往kafka写数据
        FlinkKafkaProducer kafkaproducer = new FlinkKafkaProducer<>(
                "Master:9092,Slave:9092,Slave:9092", "topic_log", new SimpleStringSchema());

        //把数据写到指定的Slink
        lines.addSink(kafkaproducer);



        env.execute();
    }

    //定义内部类
    public static class MyPrintSink extends RichSinkFunction {
        private int indexOfThisSubtask;

        //最终把数据输出的方法（如：mysql、jdbc）
        @Override
        public void invoke(String value, Context context) throws Exception {
            //：拿到索引编号[从0开始]
            RuntimeContext runtimeContext = getRuntimeContext();
            int indexOfThisSubtask = runtimeContext.getIndexOfThisSubtask();

            System.out.println(indexOfThisSubtask+"> "+value);
        }
    }

}

控制台打印输出：是一个无界流程序

查看job：http://localhost:8081/#/job/6cb13849f794d199f8bd20cb30d7c149/overview