/* * 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.beam.sdk.transforms.windowing; /** * Abstract base class for {@link WindowFn WindowFns} that do not merge windows. * * @param <T> type of elements being windowed * @param <W> {@link BoundedWindow} subclass used to represent the windows used by this * {@code WindowFn} */ public abstract class NonMergingWindowFn<T, W extends BoundedWindow> extends WindowFn<T, W> { @Override public final void mergeWindows(MergeContext c) { } @Override public final boolean isNonMerging() { return true; } }