Flink入门 - CoGroup和Join

/*
*CoGroup
*/ 

final StreamExecutionEnvironment streamExecutionEnvironment = StreamExecutionEnvironment.getExecutionEnvironment(); 

        DataStream<Tuple2<String, String>> dataStream1 = streamExecutionEnvironment.socketTextStream("127.0.0.1", 9000)
                .map(new MapFunction<String, Tuple2<String, String>>() {
                    @Override
                    public Tuple2<String, String> map(String s) throws Exception {
                        List<String> strs = Arrays.asList(s.split(" "));
                        return new Tuple2<>(strs.get(0), strs.get(1));
                    }
                }); 

        DataStream<Tuple2<String, String>> dataStream2 = streamExecutionEnvironment.socketTextStream("127.0.0.1", 9001)
                .map(new MapFunction<String, Tuple2<String, String>>() {
                    @Override
                    public Tuple2<String, String> map(String s) throws Exception {
                        List<String> strs = Arrays.asList(s.split(" "));
                        return new Tuple2<>(strs.get(0), strs.get(1));
                    }
                }); 

        dataStream1.coGroup(dataStream2)
                .where(new KeySelector<Tuple2<String, String>, String>() {
                    @Override
                    public String getKey(Tuple2<String, String> stringStringTuple2) throws Exception {
                        return stringStringTuple2.f0;
                    }
                })
                .equalTo(new KeySelector<Tuple2<String, String>, String>() {
                    @Override
                    public String getKey(Tuple2<String, String> stringStringTuple2) throws Exception {
                        return stringStringTuple2.f0;
                    }
                })
                .window(ProcessingTimeSessionWindows.withGap(Time.seconds(30)))
                .trigger(CountTrigger.of(1))
                .apply(new CoGroupFunction<Tuple2<String, String>, Tuple2<String, String>, String>() {
                    @Override
                    public void coGroup(Iterable<Tuple2<String, String>> first, Iterable<Tuple2<String, String>> second, Collector<String> out) throws Exception {
                        StringBuilder stringBuilder = new StringBuilder("Data Stream1: \n");
                        first.forEach(item -> stringBuilder.append(item.f0 + "<=>" + item.f1 + "\n")); 

                        stringBuilder.append("Data Stream2: \n");
                        second.forEach(item -> stringBuilder.append(item.f0 + "<=>" + item.f1 + "\n"));
                        out.collect(stringBuilder.toString());
                    }
                }).print(); 

        streamExecutionEnvironment.execute();

/**
* Join
* Join条件为两个流中的数据((String, String))的第一个元素相同
*/
final StreamExecutionEnvironment streamExecutionEnvironment = StreamExecutionEnvironment.getExecutionEnvironment(); 

        DataStream<Tuple2<String, String>> dataStream1 = streamExecutionEnvironment.fromElements(new Tuple2<>("hello", "flink")); 

        DataStream<Tuple2<String, String>> dataStream2 = streamExecutionEnvironment.fromElements(new Tuple2<>("hello", "blink")); 

        dataStream1.join(dataStream2)
                .where(new KeySelector<Tuple2<String, String>, String>() {
                    @Override
                    public String getKey(Tuple2<String, String> stringStringTuple2) throws Exception {
                        return stringStringTuple2.f0;
                    }
                })
                .equalTo(new KeySelector<Tuple2<String, String>, String>() {
                    @Override
                    public String getKey(Tuple2<String, String> stringStringTuple2) throws Exception {
                        return stringStringTuple2.f0;
                    }
                })
                .window(ProcessingTimeSessionWindows.withGap(Time.seconds(30)))
                .trigger(CountTrigger.of(1))
                .apply(new JoinFunction<Tuple2<String, String>, Tuple2<String, String>, String>() {
                    @Override
                    public String join(Tuple2<String, String> first, Tuple2<String, String> second) throws Exception {
                        return first.f1 + "<=>" + second.f1;
                    }
                }).print();
        streamExecutionEnvironment.execute(); 

// 运行结果
2> flink<=>blink