Examples with ProcessWindowFunction org.apache.flink.streaming.api.functions.windowing.ProcessWindowFunction used on opensource projects

Example 1 with ProcessWindowFunction

use of org.apache.flink.streaming.api.functions.windowing.ProcessWindowFunction in project flink by apache.

the class WindowFoldITCase method testFoldProcessWindow.

@Test
public void testFoldProcessWindow() throws Exception {
    testResults = new ArrayList<>();
    StreamExecutionEnvironment env = StreamExecutionEnvironment.getExecutionEnvironment();
    env.setStreamTimeCharacteristic(TimeCharacteristic.EventTime);
    env.setParallelism(1);
    DataStream<Tuple2<String, Integer>> source1 = env.addSource(new SourceFunction<Tuple2<String, Integer>>() {

        private static final long serialVersionUID = 1L;

        @Override
        public void run(SourceContext<Tuple2<String, Integer>> ctx) throws Exception {
            ctx.collect(Tuple2.of("a", 0));
            ctx.collect(Tuple2.of("a", 1));
            ctx.collect(Tuple2.of("a", 2));
            ctx.collect(Tuple2.of("b", 3));
            ctx.collect(Tuple2.of("b", 4));
            ctx.collect(Tuple2.of("b", 5));
            ctx.collect(Tuple2.of("a", 6));
            ctx.collect(Tuple2.of("a", 7));
            ctx.collect(Tuple2.of("a", 8));
        // source is finite, so it will have an implicit MAX watermark when it finishes
        }

        @Override
        public void cancel() {
        }
    }).assignTimestampsAndWatermarks(new Tuple2TimestampExtractor());
    source1.keyBy(0).window(TumblingEventTimeWindows.of(Time.of(3, TimeUnit.MILLISECONDS))).fold(Tuple2.of(0, "R:"), new FoldFunction<Tuple2<String, Integer>, Tuple2<Integer, String>>() {

        @Override
        public Tuple2<Integer, String> fold(Tuple2<Integer, String> accumulator, Tuple2<String, Integer> value) throws Exception {
            accumulator.f1 += value.f0;
            accumulator.f0 += value.f1;
            return accumulator;
        }
    }, new ProcessWindowFunction<Tuple2<Integer, String>, Tuple3<String, Integer, Integer>, Tuple, TimeWindow>() {

        @Override
        public void process(Tuple tuple, Context context, Iterable<Tuple2<Integer, String>> elements, Collector<Tuple3<String, Integer, Integer>> out) throws Exception {
            int i = 0;
            for (Tuple2<Integer, String> in : elements) {
                out.collect(new Tuple3<>(in.f1, in.f0, i++));
            }
        }
    }).addSink(new SinkFunction<Tuple3<String, Integer, Integer>>() {

        @Override
        public void invoke(Tuple3<String, Integer, Integer> value) throws Exception {
            testResults.add(value.toString());
        }
    });
    env.execute("Fold Process Window Test");
    List<String> expectedResult = Arrays.asList("(R:aaa,3,0)", "(R:aaa,21,0)", "(R:bbb,12,0)");
    Collections.sort(expectedResult);
    Collections.sort(testResults);
    Assert.assertEquals(expectedResult, testResults);
}