| /* |
| * 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.runners.flink.translation.wrappers.streaming; |
| |
| import static org.apache.beam.vendor.guava.v20_0.com.google.common.base.Preconditions.checkNotNull; |
| |
| import java.util.stream.Stream; |
| import java.util.stream.StreamSupport; |
| import org.apache.flink.api.common.state.ListState; |
| |
| /** {@link PushedBackElementsHandler} that stores elements in a Flink operator state list. */ |
| class NonKeyedPushedBackElementsHandler<T> implements PushedBackElementsHandler<T> { |
| |
| static <T> NonKeyedPushedBackElementsHandler<T> create(ListState<T> elementState) { |
| return new NonKeyedPushedBackElementsHandler<>(elementState); |
| } |
| |
| private final ListState<T> elementState; |
| |
| private NonKeyedPushedBackElementsHandler(ListState<T> elementState) { |
| this.elementState = checkNotNull(elementState); |
| } |
| |
| @Override |
| public Stream<T> getElements() throws Exception { |
| return StreamSupport.stream(elementState.get().spliterator(), false); |
| } |
| |
| @Override |
| public void clear() { |
| elementState.clear(); |
| } |
| |
| @Override |
| public void pushBack(T element) throws Exception { |
| elementState.add(element); |
| } |
| |
| @Override |
| public void pushBackAll(Iterable<T> elements) throws Exception { |
| for (T e : elements) { |
| // TODO: use addAll() once Flink has addAll(Iterable<T>) |
| elementState.add(e); |
| } |
| } |
| } |