通过循环遍历迭代器来计算迭代器中的项数。
/** * Copyright (c) 2002-2013 "Neo Technology," * Network Engine for Objects in Lund AB [http://neotechnology.com] * * This file is part of Neo4j. * * Neo4j is free software: you can redistribute it and/or modify * it under the terms of the GNU General Public License as published by * the Free Software Foundation, either version 3 of the License, or * (at your option) any later version. * * This program is distributed in the hope that it will be useful, * but WITHOUT ANY WARRANTY; without even the implied warranty of * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the * GNU General Public License for more details. * * You should have received a copy of the GNU General Public License * along with this program. If not, see <http://www.gnu.org/licenses/>. */ //package com.nowjava; /** * n o w j a v a . c o m 提 供 **/ import java.util.Iterator; public class Main { /** * Counts the number of items in the {@code iterator} by looping * through it. * @param <T> the type of items in the iterator. * @param iterator the {@link Iterator} to count items in. * @return the number of found in {@code iterator}. */ public static <T> int count(Iterator<T> iterator) { int result = 0; while (iterator.hasNext()) { iterator.next(); result++; }//时 代 J a v a 提供 return result; }