content: /*
   * 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.
   */
  /**
   * Defines the {@link org.apache.beam.sdk.transforms.windowing.Window} transform for dividing the
   * elements in a PCollection into windows, and the {@link
   * org.apache.beam.sdk.transforms.windowing.Trigger} for controlling when those elements are output.
   *
   * <p>{@code Window} logically divides up or groups the elements of a {@link
   * org.apache.beam.sdk.values.PCollection} into finite windows according to a {@link
   * org.apache.beam.sdk.transforms.windowing.WindowFn}. The output of {@code Window} contains the
   * same elements as input, but they have been logically assigned to windows. The next {@link
   * org.apache.beam.sdk.transforms.GroupByKey}s, including one within composite transforms, will
   * group by the combination of keys and windows.
   *
   * <p>Windowing a {@code PCollection} allows chunks of it to be processed individually, before the
   * entire {@code PCollection} is available. This is especially important for {@code PCollection}s
   * with unbounded size, since the full {@code PCollection} is never available at once.
   *
   * <p>For {@code PCollection}s with a bounded size, by default, all data is implicitly in a single
   * window, and this replicates conventional batch mode. However, windowing can still be a convenient
   * way to express time-sliced algorithms over bounded {@code PCollection}s.
   *
   * <p>As elements are assigned to a window, they are placed into a pane. When the trigger fires all
   * of the elements in the current pane are output.
   *
   * <p>The {@link org.apache.beam.sdk.transforms.windowing.DefaultTrigger} will output a window when
   * the system watermark passes the end of the window. See {@link
   * org.apache.beam.sdk.transforms.windowing.AfterWatermark} for details on the watermark.
   */
  @DefaultAnnotation(NonNull.class)
  package org.apache.beam.sdk.transforms.windowing;
  
  import edu.umd.cs.findbugs.annotations.DefaultAnnotation;
  import org.checkerframework.checker.nullness.qual.NonNull;
  