03_Flink Streaming SinkFunction

env对象的addSink（SinkFunction）。需要传入一个SinkFunction对象。这个对象处理的出口。之后无法再进行数据操作。

package com.alibaba.flink.train.streaming;import org.apache.flink.configuration.Configuration;import org.apache.flink.streaming.api.functions.sink.RichSinkFunction;import org.apache.flink.streaming.api.functions.sink.SinkFunction;public class MemSink<T> implements SinkFunction<T> {/** * 没过来一条数据调用一次 */@Overridepublic void invoke(T value) throws Exception {System.out.println("MemSink:" + value);}}class RSink extends RichSinkFunction<String> {@Overridepublic void open(Configuration parameters) throws Exception {super.open(parameters);}@Overridepublic void invoke(String value) throws Exception {}@Overridepublic void close() throws Exception {super.close();}}

package com.alibaba.flink.train.streaming;import org.apache.flink.api.common.functions.FlatMapFunction;import org.apache.flink.api.java.tuple.Tuple2;import org.apache.flink.streaming.api.datastream.DataStream;import org.apache.flink.streaming.api.environment.StreamExecutionEnvironment;import org.apache.flink.util.Collector;public class HelloWorld {public static void main(String[] args) throws Exception {StreamExecutionEnvironment env = StreamExecutionEnvironment.getExecutionEnvironment();// env.setParallelism(4);//并发度DataStream<String> dataStream = env.readTextFile("D:/flinkdata/helloworld"); // 1:(flink storm// )(hadoop hive)dataStream = env.addSource(new MemSource());dataStream.flatMap(new FlatMapFunction<String, Tuple2<String, Integer>>() {@Overridepublic void flatMap(String input,Collector<Tuple2<String, Integer>> collector)throws Exception {String[] objs = input.split(" ");for (String obj : objs) {collector.collect(new Tuple2<String, Integer>(obj, 1));// (这里很关键，表示0位置是word，1的位置是1次数)}}})// 2:(flink 1)(storm 1).keyBy(0)// 3:以第0个位置的值，做分区。.sum(1)// (flink:8)(storm:5)，对第1个位置的值做sum的操作。.addSink(new MemSink());//.printToErr();env.execute();// 启动任务while (true) {}}}

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