Here you can find the source of mkDir(File dir)
public static void mkDir(File dir)
//package com.java2s; /**//from w w w . j a v a 2 s . c o m * Licensed to the Apache Software Foundation (ASF) under one * or more contributor license agreements. See the NOTICE file * distributed with this work for additional information * regarding copyright ownership. The ASF licenses this file * to you 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.io.File; public class Main { private static final int RETRY_SLEEP_MILLIS = 10; public static void mkDir(File dir) { if (dir == null) { throw new RuntimeException("dir attribute is required"); } if (dir.isFile()) { throw new RuntimeException("Unable to create directory as a file " + "already exists with that name: " + dir.getAbsolutePath()); } if (!dir.exists()) { boolean result = doMkDirs(dir); if (!result) { String msg = "Directory " + dir.getAbsolutePath() + " creation was not successful for an unknown reason"; throw new RuntimeException(msg); } } } /** * Attempt to fix possible race condition when creating directories on * WinXP, also Windows2000. If the mkdirs does not work, wait a little and * try again. */ private static boolean doMkDirs(File f) { if (!f.mkdirs()) { try { Thread.sleep(RETRY_SLEEP_MILLIS); return f.mkdirs(); } catch (InterruptedException ex) { return f.mkdirs(); } } return true; } }