use of org.apache.beam.runners.core.OutputWindowedValue in project beam by apache.
the class BatchGroupAlsoByWindowViaIteratorsFn method processElement.
@Override
@SuppressWarnings("ReferenceEquality")
public void processElement(KV<K, Iterable<WindowedValue<V>>> element, PipelineOptions options, StepContext stepContext, SideInputReader sideInputReader, OutputWindowedValue<KV<K, Iterable<V>>> output) throws Exception {
K key = element.getKey();
// This iterable is required to be in order of increasing timestamps
Iterable<WindowedValue<V>> value = element.getValue();
PeekingReiterator<WindowedValue<V>> iterator;
if (value instanceof Collection) {
iterator = new PeekingReiterator<>(new ListReiterator<WindowedValue<V>>(new ArrayList<WindowedValue<V>>((Collection<WindowedValue<V>>) value), 0));
} else if (value instanceof Reiterable) {
iterator = new PeekingReiterator<>(((Reiterable<WindowedValue<V>>) value).iterator());
} else {
throw new IllegalArgumentException("Input to GroupAlsoByWindowsDoFn must be a Collection or Reiterable");
}
// This ListMultimap is a map of window maxTimestamps to the list of active
// windows with that maxTimestamp.
ListMultimap<Instant, BoundedWindow> windows = ArrayListMultimap.create();
while (iterator.hasNext()) {
WindowedValue<V> e = iterator.peek();
for (BoundedWindow window : e.getWindows()) {
// corresponding to this window, starting at this element in the input Reiterable.
if (!windows.containsEntry(window.maxTimestamp(), window)) {
// This window was produced by strategy.getWindowFn()
@SuppressWarnings("unchecked") W typedWindow = (W) window;
// Iterating through the WindowReiterable may advance iterator as an optimization
// for as long as it detects that there are no new windows.
windows.put(window.maxTimestamp(), window);
output.outputWindowedValue(KV.of(key, (Iterable<V>) new WindowReiterable<V>(iterator, window)), strategy.getTimestampCombiner().assign(typedWindow, e.getTimestamp()), Arrays.asList(window), PaneInfo.ON_TIME_AND_ONLY_FIRING);
}
}
// Copy the iterator in case the next DoFn cached its version of the iterator instead
// of immediately iterating through it.
// And, only advance the iterator if the consuming operation hasn't done so.
iterator = iterator.copy();
if (iterator.hasNext() && iterator.peek() == e) {
iterator.next();
}
// Remove all windows with maxTimestamp behind the current timestamp.
Iterator<Instant> windowIterator = windows.keys().iterator();
while (windowIterator.hasNext() && windowIterator.next().isBefore(e.getTimestamp())) {
windowIterator.remove();
}
}
}
Aggregations