package com.thinker;

import org.apache.flink.api.common.functions.FlatMapFunction;
import org.apache.flink.api.java.tuple.Tuple2;
import org.apache.flink.streaming.api.datastream.DataStreamSource;
import org.apache.flink.streaming.api.datastream.SingleOutputStreamOperator;
import org.apache.flink.streaming.api.environment.StreamExecutionEnvironment;
import org.apache.flink.util.Collector;

/**
 * Hello world!
 */
public class App {

    public static final class LineSplitter implements FlatMapFunction<String, Tuple2<String, Integer>> {

        @Override
        public void flatMap(String s, Collector<Tuple2<String, Integer>> collector) throws Exception {
            String[] tokens = s.toLowerCase().split("\\W+");
            for (String token: tokens){
                if (token.length() > 0){
                    collector.collect(new Tuple2<String, Integer>(token, 1));
                }
            }
        }
    }

    public static void main(String[] args) throws Exception {
        System.out.println("Hello World!");
        if (args.length != 2) {
            System.err.println("USAGE:\nSocketTextStreamWordCount <hostname> <port>");
            return;
        }
        String hostname = args[0];
        Integer port = Integer.parseInt(args[1]);

        final StreamExecutionEnvironment env = StreamExecutionEnvironment.getExecutionEnvironment();

        DataStreamSource<String> streamSource = env.socketTextStream(hostname, port);

        SingleOutputStreamOperator<Tuple2<String, Integer>> sum = streamSource.flatMap(new LineSplitter())
                .keyBy(0).sum(1);
        sum.print();
        env.execute("Java WordCount from SocketTextStream Example");
    }
}