content: /*
   * Copyright (C) 2020 ActiveJ LLC.
   *
   * Licensed 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 io.activej.datastream.consumer;
  
  import io.activej.promise.Promise;
  import io.activej.promise.SettablePromise;
  
  import java.util.ArrayList;
  import java.util.List;
  
  /**
   * Accumulates items from this supplier until it closes and
   * then completes the returned promise with a list of those items.
   */
  public final class ToListStreamConsumer<T> extends AbstractStreamConsumer<T> {
  	private final SettablePromise<List<T>> resultPromise = new SettablePromise<>();
  	private final List<T> list;
  
  	private ToListStreamConsumer(List<T> list) {
  		this.list = list;
  	}
  
  	public static <T> ToListStreamConsumer<T> create() {
  		return create(new ArrayList<>());
  	}
  
  	public static <T> ToListStreamConsumer<T> create(List<T> list) {
  		return new ToListStreamConsumer<>(list);
  	}
  
  	public Promise<List<T>> getResult() {
  		return resultPromise;
  	}
  
  	public List<T> getList() {
  		return list;
  	}
  
  	@Override
  	protected void onInit() {
  		resultPromise.whenResult(this::acknowledge);
  	}
  
  	@Override
  	protected void onStarted() {
  		resume(list::add);
  	}
  
  	@Override
  	protected void onEndOfStream() {
  		resultPromise.set(list);
  	}
  
  	@Override
  	protected void onError(Exception e) {
  		resultPromise.setException(e);
  	}
  }
  