Here you can find the source of checkDirectory(File dir)
public static void checkDirectory(File dir)
//package com.java2s; /**//from w w w. j a v a 2 s . c om * 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 { /** Check local directory. */ public static void checkDirectory(File dir) { if (!dir.exists()) if (!dir.mkdirs()) throw new IllegalArgumentException("!dir.mkdirs(), dir=" + dir); if (!dir.isDirectory()) throw new IllegalArgumentException("dir (=" + dir + ") is not a directory."); } }