Here you can find the source of mkdirs(File dir)
public static File mkdirs(File dir)
//package com.java2s; /******************************************************************************************* * Copyright (c) 2016, zzg.zhou(11039850@qq.com) * /* w w w . j ava2 s . c om*/ * Monalisa 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 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 Lesser General Public License for more details. * You should have received a copy of the GNU Lesser General Public License * along with this program. If not, see <http://www.gnu.org/licenses/>. *******************************************************************************************/ import java.io.File; public class Main { public static File mkdirs(String dir) { return mkdirs(new File(dir)); } public static File mkdirs(File dir) { if (!dir.exists()) { dir.mkdirs(); } return dir; } }