Here you can find the source of toStringArray(Collection
public static String[] toStringArray(Collection<String> list)
//package com.java2s; /*/*from w w w . j a v a 2 s. co m*/ * Copyright (c) 2012-2015, Bernhard Haumacher. * All rights reserved. * * This library is free software; you can redistribute it and/or * modify it under the terms of the GNU Lesser General Public * License as published by the Free Software Foundation; either * version 3 of the License, or (at your option) any later version. * * This library 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 * Lesser General Public License for more details. * * You should have received a copy of the GNU Lesser General Public * License along with this library; if not, write to the Free Software * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, * MA 02110-1301 USA */ import java.util.Collection; public class Main { /** * Converts a collection of {@link String}s to a {@link String} array. */ public static String[] toStringArray(Collection<String> list) { return list.toArray(new String[list.size()]); } }