Here you can find the source of copy(Iterator
public static <T> Iterator<T> copy(Iterator<T> iterator)
//package com.java2s; /*/* w w w. j a va2s. c om*/ * Copyright 2004-2010 the Seasar Foundation and the Others. * * 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. */ import java.util.Iterator; import java.util.LinkedList; import java.util.List; public class Main { public static <T> Iterator<T> copy(Iterator<T> iterator) { List<T> list = toList(iterator); return list.iterator(); } public static <T> List<T> toList(Iterator<T> iterator) { List<T> list = new LinkedList<>(); iterator.forEachRemaining(list::add); return list; } }