1 // Copyright 2013 The Chromium Authors. All rights reserved. 2 // Use of this source code is governed by a BSD-style license that can be 3 // found in the LICENSE file. 4 5 package org.chromium.base; 6 7 import java.util.ArrayList; 8 import java.util.Collections; 9 import java.util.HashSet; 10 11 /** 12 * Functions used for easier initialization of Java collections. Inspired by 13 * functionality in com.google.common.collect in Guava but cherry-picked to 14 * bare-minimum functionality to avoid bloat. (http://crbug.com/272790 provides 15 * further details) 16 */ 17 public final class CollectionUtil { CollectionUtil()18 private CollectionUtil() {} 19 20 @SafeVarargs newHashSet(E... elements)21 public static <E> HashSet<E> newHashSet(E... elements) { 22 HashSet<E> set = new HashSet<E>(elements.length); 23 Collections.addAll(set, elements); 24 return set; 25 } 26 27 @SafeVarargs newArrayList(E... elements)28 public static <E> ArrayList<E> newArrayList(E... elements) { 29 ArrayList<E> list = new ArrayList<E>(elements.length); 30 Collections.addAll(list, elements); 31 return list; 32 } 33 34 @VisibleForTesting newArrayList(Iterable<E> iterable)35 public static <E> ArrayList<E> newArrayList(Iterable<E> iterable) { 36 ArrayList<E> list = new ArrayList<E>(); 37 for (E element : iterable) { 38 list.add(element); 39 } 40 return list; 41 } 42 }