Java tutorial
/** * Copyright (C) 2008 Progress Software, Inc. All rights reserved. * http://fusesource.com * * The software in this package is published under the terms of the AGPL license * a copy of which has been included with this distribution in the license.txt file. */ package org.fusesource.cloudmix.common.util; import java.io.BufferedReader; import java.io.File; import java.io.FileReader; import java.io.IOException; import java.io.InputStream; import java.io.OutputStream; import org.apache.commons.logging.Log; import org.apache.commons.logging.LogFactory; public final class FileUtils { public static final int BUFFER_SIZE = 1024; private static final Log LOGGER = LogFactory.getLog(FileUtils.class); private FileUtils() { /* Utility classes should not have a public constructor */ } public static File createDirectory(File parentDir, String path) { File dir = parentDir == null ? new File(path) : new File(parentDir, path); return createDirectory(dir); } public static File createDirectory(File dir) { if (!dir.exists()) { LOGGER.info("Creating work directory " + dir); if (!dir.mkdirs()) { LOGGER.error("failed to make work directory " + dir); return null; } } return dir; } public static void deleteDirectory(File dir) { LOGGER.info("deleting directory " + dir); File[] files = dir.listFiles(); if (files != null) { for (File f : files) { if (f.isDirectory()) { deleteDirectory(f); } else { f.delete(); } } dir.delete(); } } public static void deleteFile(File file) { LOGGER.info("deleting file " + file); if (!file.delete()) { LOGGER.warn("failed to delete file " + file); } } public static void copy(InputStream is, OutputStream os) throws IOException { copy(is, os, BUFFER_SIZE); } public static void copy(InputStream is, OutputStream os, int bufferSize) throws IOException { final byte[] buffer = new byte[bufferSize]; long total = 0; int n = is.read(buffer); while (n != -1) { total += n; os.write(buffer, 0, n); n = is.read(buffer); } LOGGER.info("Copied " + total + " bytes"); is.close(); os.close(); } public static String readFile(String path) throws IOException { return readFile(new File(path)); } public static String readFile(File file) throws IOException { StringBuilder sb = new StringBuilder(); BufferedReader reader = new BufferedReader(new FileReader(file)); char[] chars = new char[BUFFER_SIZE]; int length; while ((length = reader.read(chars)) > 0) { sb.append(chars, 0, length); } reader.close(); return sb.toString(); } }