How to use

reduceByWindow

method

in

org.apache.spark.streaming.api.java.JavaDStream

public Long call(ApacheAccessLog entry) {
 return 1L;
}}).reduceByWindow(new Function2<Long, Long, Long>() {
  public Long call(Long v1, Long v2) {
   return v1+v2;

@Test
public void testReduceByWindow() {
 List<List<Integer>> inputData = Arrays.asList(
  Arrays.asList(1, 2, 3),
  Arrays.asList(4, 5, 6),
  Arrays.asList(7, 8, 9));
 List<List<Integer>> expected = Arrays.asList(
  Arrays.asList(6),
  Arrays.asList(21),
  Arrays.asList(39),
  Arrays.asList(24));
 JavaDStream<Integer> stream = JavaTestUtils.attachTestInputStream(ssc, inputData, 1);
 JavaDStream<Integer> reducedWindowed = stream.reduceByWindow(
  (x, y) -> x + y, (x, y) -> x - y, new Duration(2000), new Duration(1000));
 JavaTestUtils.attachTestOutputStream(reducedWindowed);
 List<List<Integer>> result = JavaTestUtils.runStreams(ssc, 4, 4);
 Assert.assertEquals(expected, result);
}

@Test
public void testReduceByWindow() {
 List<List<Integer>> inputData = Arrays.asList(
  Arrays.asList(1, 2, 3),
  Arrays.asList(4, 5, 6),
  Arrays.asList(7, 8, 9));
 List<List<Integer>> expected = Arrays.asList(
  Arrays.asList(6),
  Arrays.asList(21),
  Arrays.asList(39),
  Arrays.asList(24));
 JavaDStream<Integer> stream = JavaTestUtils.attachTestInputStream(ssc, inputData, 1);
 JavaDStream<Integer> reducedWindowed = stream.reduceByWindow(
  (x, y) -> x + y, (x, y) -> x - y, new Duration(2000), new Duration(1000));
 JavaTestUtils.attachTestOutputStream(reducedWindowed);
 List<List<Integer>> result = JavaTestUtils.runStreams(ssc, 4, 4);
 Assert.assertEquals(expected, result);
}

@SuppressWarnings("unchecked")
private void testReduceByWindow(boolean withInverse) {
 List<List<Integer>> inputData = Arrays.asList(
   Arrays.asList(1,2,3),
   Arrays.asList(4,5,6),
   Arrays.asList(7,8,9));
 List<List<Integer>> expected = Arrays.asList(
   Arrays.asList(6),
   Arrays.asList(21),
   Arrays.asList(39),
   Arrays.asList(24));
 JavaDStream<Integer> stream = JavaTestUtils.attachTestInputStream(ssc, inputData, 1);
 JavaDStream<Integer> reducedWindowed;
 if (withInverse) {
  reducedWindowed = stream.reduceByWindow(new IntegerSum(),
                      new IntegerDifference(),
                      new Duration(2000),
                      new Duration(1000));
 } else {
  reducedWindowed = stream.reduceByWindow(new IntegerSum(),
                      new Duration(2000), new Duration(1000));
 }
 JavaTestUtils.attachTestOutputStream(reducedWindowed);
 List<List<Integer>> result = JavaTestUtils.runStreams(ssc, 4, 4);
 Assert.assertEquals(expected, result);
}

@SuppressWarnings("unchecked")
private void testReduceByWindow(boolean withInverse) {
 List<List<Integer>> inputData = Arrays.asList(
   Arrays.asList(1,2,3),
   Arrays.asList(4,5,6),
   Arrays.asList(7,8,9));
 List<List<Integer>> expected = Arrays.asList(
   Arrays.asList(6),
   Arrays.asList(21),
   Arrays.asList(39),
   Arrays.asList(24));
 JavaDStream<Integer> stream = JavaTestUtils.attachTestInputStream(ssc, inputData, 1);
 JavaDStream<Integer> reducedWindowed;
 if (withInverse) {
  reducedWindowed = stream.reduceByWindow(new IntegerSum(),
                      new IntegerDifference(),
                      new Duration(2000),
                      new Duration(1000));
 } else {
  reducedWindowed = stream.reduceByWindow(new IntegerSum(),
                      new Duration(2000), new Duration(1000));
 }
 JavaTestUtils.attachTestOutputStream(reducedWindowed);
 List<List<Integer>> result = JavaTestUtils.runStreams(ssc, 4, 4);
 Assert.assertEquals(expected, result);
}