Here you can find the source of copyColl(Collection out, Iterable set)
@SuppressWarnings("unchecked") public static void copyColl(Collection<?> out, Iterable<?> set)
//package com.java2s; /******************************************************************************* * The MIT License (MIT)/*from ww w.j a v a 2s . co m*/ * * Copyright (c) 2016 Dalibor Drgo? <emptychannelmc@gmail.com> * * Permission is hereby granted, free of charge, to any person obtaining a copy * of this software and associated documentation files (the "Software"), to deal * in the Software without restriction, including without limitation the rights * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell * copies of the Software, and to permit persons to whom the Software is * furnished to do so, subject to the following conditions: * * The above copyright notice and this permission notice shall be included in * all copies or substantial portions of the Software. * * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN * THE SOFTWARE. ******************************************************************************/ import java.util.Collection; import java.util.Iterator; public class Main { @SuppressWarnings("unchecked") public static void copyColl(Collection<?> out, Iterable<?> set) { Iterator<?> it = set.iterator(); while (it.hasNext()) { ((Collection<Object>) out).add(it.next()); } } }