Here you can find the source of asArrayList(E first, E... other)
public static <E> ArrayList<E> asArrayList(E first, E... other)
//package com.java2s; /*//from w w w. ja va 2 s. c o m * Licensed to Elasticsearch under one or more contributor * license agreements. See the NOTICE file distributed with * this work for additional information regarding copyright * ownership. Elasticsearch 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. */ import java.util.ArrayList; import java.util.Arrays; public class Main { public static <E> ArrayList<E> asArrayList(E first, E... other) { if (other == null) { throw new NullPointerException("other"); } ArrayList<E> list = new ArrayList<>(1 + other.length); list.add(first); list.addAll(Arrays.asList(other)); return list; } public static <E> ArrayList<E> asArrayList(E first, E second, E... other) { if (other == null) { throw new NullPointerException("other"); } ArrayList<E> list = new ArrayList<>(1 + 1 + other.length); list.add(first); list.add(second); list.addAll(Arrays.asList(other)); return list; } }