1 /* 2 * Licensed to the Apache Software Foundation (ASF) under one 3 * or more contributor license agreements. See the NOTICE file 4 * distributed with this work for additional information 5 * regarding copyright ownership. The ASF licenses this file 6 * to you under the Apache License, Version 2.0 (the 7 * "License"); you may not use this file except in compliance 8 * with the License. You may obtain a copy of the License at 9 * 10 * http://www.apache.org/licenses/LICENSE-2.0 11 * 12 * Unless required by applicable law or agreed to in writing, 13 * software distributed under the License is distributed on an 14 * "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY 15 * KIND, either express or implied. See the License for the 16 * specific language governing permissions and limitations 17 * under the License. 18 */ 19 20 package org.apache.commons.compress.utils; 21 22 import java.util.Collection; 23 import java.util.Iterator; 24 import java.util.Objects; 25 26 /** 27 * Iterator utilities. 28 * 29 * @since 1.13. 30 */ 31 public class Iterators { 32 33 /** 34 * Adds all the elements in the source {@code iterator} to the target {@code collection}. 35 * 36 * <p> 37 * When this method returns, the {@code iterator} will be "empty": its {@code hasNext()} method returns {@code false}. 38 * </p> 39 * 40 * @param <T> type of the elements contained inside the collection 41 * @param collection target collection 42 * @param iterator source 43 * @return {@code true} if the target {@code collection} was modified as a result of this operation 44 */ 45 public static <T> boolean addAll(final Collection<T> collection, final Iterator<? extends T> iterator) { 46 Objects.requireNonNull(collection); 47 Objects.requireNonNull(iterator); 48 boolean wasModified = false; 49 while (iterator.hasNext()) { 50 wasModified |= collection.add(iterator.next()); 51 } 52 return wasModified; 53 } 54 55 private Iterators() { 56 // do not instantiate 57 } 58 59 }