| /* |
| * Licensed to the Apache Software Foundation (ASF) under one |
| * or more contributor license agreements. See the NOTICE file |
| * distributed with this work for additional information |
| * regarding copyright ownership. The ASF licenses this file |
| * to you under the Apache License, Version 2.0 (the |
| * "License"); you may not use this file except in compliance |
| * with the License. You may obtain a copy of the License at |
| * |
| * http://www.apache.org/licenses/LICENSE-2.0 |
| * |
| * Unless required by applicable law or agreed to in writing, |
| * software distributed under the License is distributed on an |
| * "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY |
| * KIND, either express or implied. See the License for the |
| * specific language governing permissions and limitations |
| * under the License. |
| */ |
| package org.apache.nemo.compiler.frontend.beam.transform; |
| |
| import com.google.common.collect.Iterables; |
| import org.apache.beam.sdk.transforms.display.DisplayData; |
| import org.apache.beam.sdk.transforms.windowing.BoundedWindow; |
| import org.apache.beam.sdk.transforms.windowing.PaneInfo; |
| import org.apache.beam.sdk.transforms.windowing.WindowFn; |
| import org.apache.beam.sdk.util.WindowedValue; |
| import org.apache.nemo.common.ir.OutputCollector; |
| import org.apache.nemo.common.ir.vertex.transform.Transform; |
| import org.apache.nemo.common.punctuation.Watermark; |
| import org.joda.time.Instant; |
| |
| import java.util.Collection; |
| |
| /** |
| * Windowing transform implementation. |
| * This transform simply windows the given elements into |
| * finite windows according to a user-specified WindowFnTransform. |
| * |
| * @param <T> input/output type. |
| * @param <W> window type |
| */ |
| public final class WindowFnTransform<T, W extends BoundedWindow> |
| implements Transform<WindowedValue<T>, WindowedValue<T>> { |
| private final WindowFn windowFn; |
| private final DisplayData displayData; |
| private OutputCollector<WindowedValue<T>> outputCollector; |
| |
| /** |
| * Default Constructor. |
| * |
| * @param windowFn windowFn for the Transform. |
| * @param displayData display data. |
| */ |
| public WindowFnTransform(final WindowFn windowFn, final DisplayData displayData) { |
| this.windowFn = windowFn; |
| this.displayData = displayData; |
| } |
| |
| @Override |
| public void prepare(final Context context, final OutputCollector<WindowedValue<T>> oc) { |
| this.outputCollector = oc; |
| } |
| |
| @Override |
| public void onData(final WindowedValue<T> windowedValue) { |
| final BoundedWindow boundedWindow = Iterables.getOnlyElement(windowedValue.getWindows()); |
| final T element = windowedValue.getValue(); |
| final Instant timestamp = windowedValue.getTimestamp(); |
| |
| try { |
| final Collection<W> windows = |
| ((WindowFn<T, W>) windowFn) |
| .assignWindows( |
| ((WindowFn<T, W>) windowFn).new AssignContext() { |
| @Override |
| public T element() { |
| return element; |
| } |
| |
| @Override |
| public Instant timestamp() { |
| return timestamp; |
| } |
| |
| @Override |
| public BoundedWindow window() { |
| return boundedWindow; |
| } |
| }); |
| |
| // Emit compressed windows for efficiency |
| outputCollector.emit(WindowedValue.of(element, timestamp, windows, PaneInfo.NO_FIRING)); |
| } catch (final Exception e) { |
| throw new RuntimeException(e); |
| } |
| } |
| |
| @Override |
| public void onWatermark(final Watermark watermark) { |
| outputCollector.emitWatermark(watermark); |
| } |
| |
| @Override |
| public void close() { |
| } |
| |
| @Override |
| public String toString() { |
| final StringBuilder sb = new StringBuilder(); |
| sb.append("WindowFnTransform / " + displayData.toString().replaceAll(":", " / ")); |
| return sb.toString(); |
| } |
| } |