Java tutorial
/* * 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. */ package org.apache.ode.utils.fs; import java.io.File; import java.io.FileFilter; import java.util.ArrayList; import java.util.List; import java.util.TreeSet; import org.apache.commons.logging.Log; import org.apache.commons.logging.LogFactory; /** * Various file system utilities. */ public class FileUtils { private static final Log __log = LogFactory.getLog(FileUtils.class); /** * Test if the given path is absolute or not. * @param path * @return true is absolute * @see java.io.File#isAbsolute() */ public static boolean isAbsolute(String path) { return new File(path).isAbsolute(); } /** * Test if the given path is relative or absolute. * @param path * @return true is relative * @see java.io.File#isAbsolute() */ public static boolean isRelative(String path) { return !isAbsolute(path); } /** * Delete a file/directory, recursively. * * @param file * file/directory to delete * @return <code>true</code> if successful */ public static boolean deepDelete(File file) { if (file.exists()) { if (__log.isDebugEnabled()) { __log.debug("deleting: " + file.getAbsolutePath()); } if (file.delete()) { return true; } if (file.isDirectory()) { boolean success = true; File[] files = file.listFiles(); for (int i = 0; i < files.length; ++i) { success &= deepDelete(files[i]); } return success ? file.delete() : false; } else { __log.error("Unable to deepDelete file " + file.getAbsolutePath() + "; this may be caused by a descriptor leak and should be reported."); return false; } } else { // file seems to be gone already?! anyway nothing to do for us. return true; } } /** * Recursively collect all Files in the given directory and all its * subdirectories. * * @param rootDirectory * the top level directory used for the search * @return a List of found Files */ public static List<File> directoryEntriesInPath(File rootDirectory) { return FileUtils.directoryEntriesInPath(rootDirectory, null); } /** * Recursively collect all Files in the given directory and all its * subdirectories, applying the given FileFilter. The FileFilter is also applied to the given rootDirectory. * As a result the rootDirectory might be in the returned list. * <p> * Returned files are ordered lexicographically but for each directory, files come before its sudirectories. * For instance:<br/> * test<br/> * test/alpha.txt<br/> * test/zulu.txt<br/> * test/a<br/> * test/a/alpha.txt<br/> * test/z<br/> * test/z/zulu.txt<br/> * <p> * instead of:<br/> * test<br/> * test/a<br/> * test/a/alpha.txt<br/> * test/alpha.txt<br/> * test/z<br/> * test/z/zulu.txt<br/> * test/zulu.txt<br/> * * @param rootDirectory * the top level directory used for the search * @param filter * a FileFilter used for accepting/rejecting individual entries * @return a List of found Files */ public static List<File> directoryEntriesInPath(File rootDirectory, FileFilter filter) { if (rootDirectory == null) { throw new IllegalArgumentException("File must not be null!"); } if (!rootDirectory.exists()) { throw new IllegalArgumentException("File does not exist!"); } ArrayList<File> collectedFiles = new ArrayList<File>(32); if (rootDirectory.isFile()) { if ((filter == null) || ((filter != null) && (filter.accept(rootDirectory)))) { collectedFiles.add(rootDirectory); } return collectedFiles; } FileUtils.directoryEntriesInPath(collectedFiles, rootDirectory, filter); return collectedFiles; } private static void directoryEntriesInPath(List<File> collectedFiles, File parentDir, FileFilter filter) { if ((filter == null) || ((filter != null) && (filter.accept(parentDir)))) { collectedFiles.add(parentDir); } File[] allFiles = parentDir.listFiles(); if (allFiles != null) { TreeSet<File> dirs = new TreeSet<File>(); TreeSet<File> acceptedFiles = new TreeSet<File>(); for (File f : allFiles) { if (f.isDirectory()) { dirs.add(f); } else { if ((filter == null) || ((filter != null) && (filter.accept(f)))) { acceptedFiles.add(f); } } } collectedFiles.addAll(acceptedFiles); for (File currentFile : dirs) { FileUtils.directoryEntriesInPath(collectedFiles, currentFile, filter); } } } public static String encodePath(String path) { return path.replaceAll(" ", "%20"); } public static void main(String[] args) { List<File> l = directoryEntriesInPath(new File("/tmp/test")); for (File f : l) System.out.println(f); System.out.println("########"); TreeSet<File> s = new TreeSet(l); for (File f : s) System.out.println(f); } }