Here you can find the source of newArrayDeque()
public static <T> ArrayDeque<T> newArrayDeque()
//package com.java2s; /*/* w w w. j a v a 2s. c om*/ * Copyright 2014 the original author or authors. * * 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. * * Create Date : 2014-9-29 */ import java.util.ArrayDeque; import java.util.Collection; public class Main { public static <T> ArrayDeque<T> newArrayDeque() { return newArrayDeque(null); } public static <T> ArrayDeque<T> newArrayDeque(Collection<? extends T> collection) { return collection != null ? new ArrayDeque<T>(collection) : new ArrayDeque<T>(); } }