/src/main/java/org/apache/commons/io/FileSystemUtils.java
Java | 538 lines | 346 code | 15 blank | 177 comment | 30 complexity | 1b8f7b04a77a7269ecc5cf66578abe55 MD5 | raw file
Possible License(s): Apache-2.0
- /*
- * 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.commons.io;
- import java.io.BufferedReader;
- import java.io.File;
- import java.io.IOException;
- import java.io.InputStream;
- import java.io.InputStreamReader;
- import java.io.OutputStream;
- import java.util.ArrayList;
- import java.util.Arrays;
- import java.util.List;
- import java.util.Locale;
- import java.util.StringTokenizer;
- /**
- * General File System utilities.
- * <p>
- * This class provides static utility methods for general file system
- * functions not provided via the JDK {@link java.io.File File} class.
- * <p>
- * The current functions provided are:
- * <ul>
- * <li>Get the free space on a drive
- * </ul>
- *
- * @version $Id$
- * @since 1.1
- */
- public class FileSystemUtils {
- /** Singleton instance, used mainly for testing. */
- private static final FileSystemUtils INSTANCE = new FileSystemUtils();
- /** Operating system state flag for error. */
- private static final int INIT_PROBLEM = -1;
- /** Operating system state flag for neither Unix nor Windows. */
- private static final int OTHER = 0;
- /** Operating system state flag for Windows. */
- private static final int WINDOWS = 1;
- /** Operating system state flag for Unix. */
- private static final int UNIX = 2;
- /** Operating system state flag for Posix flavour Unix. */
- private static final int POSIX_UNIX = 3;
- /** The operating system flag. */
- private static final int OS;
- /** The path to df */
- private static final String DF;
- static {
- int os = OTHER;
- String dfPath = "df";
- try {
- String osName = System.getProperty("os.name");
- if (osName == null) {
- throw new IOException("os.name not found");
- }
- osName = osName.toLowerCase(Locale.ENGLISH);
- // match
- if (osName.indexOf("windows") != -1) {
- os = WINDOWS;
- } else if (osName.indexOf("linux") != -1 ||
- osName.indexOf("mpe/ix") != -1 ||
- osName.indexOf("freebsd") != -1 ||
- osName.indexOf("irix") != -1 ||
- osName.indexOf("digital unix") != -1 ||
- osName.indexOf("unix") != -1 ||
- osName.indexOf("mac os x") != -1) {
- os = UNIX;
- } else if (osName.indexOf("sun os") != -1 ||
- osName.indexOf("sunos") != -1 ||
- osName.indexOf("solaris") != -1) {
- os = POSIX_UNIX;
- dfPath = "/usr/xpg4/bin/df";
- } else if (osName.indexOf("hp-ux") != -1 ||
- osName.indexOf("aix") != -1) {
- os = POSIX_UNIX;
- } else {
- os = OTHER;
- }
- } catch (Exception ex) {
- os = INIT_PROBLEM;
- }
- OS = os;
- DF = dfPath;
- }
- /**
- * Instances should NOT be constructed in standard programming.
- */
- public FileSystemUtils() {
- super();
- }
- //-----------------------------------------------------------------------
- /**
- * Returns the free space on a drive or volume by invoking
- * the command line.
- * This method does not normalize the result, and typically returns
- * bytes on Windows, 512 byte units on OS X and kilobytes on Unix.
- * As this is not very useful, this method is deprecated in favour
- * of {@link #freeSpaceKb(String)} which returns a result in kilobytes.
- * <p>
- * Note that some OS's are NOT currently supported, including OS/390,
- * OpenVMS.
- * <pre>
- * FileSystemUtils.freeSpace("C:"); // Windows
- * FileSystemUtils.freeSpace("/volume"); // *nix
- * </pre>
- * The free space is calculated via the command line.
- * It uses 'dir /-c' on Windows and 'df' on *nix.
- *
- * @param path the path to get free space for, not null, not empty on Unix
- * @return the amount of free drive space on the drive or volume
- * @throws IllegalArgumentException if the path is invalid
- * @throws IllegalStateException if an error occurred in initialisation
- * @throws IOException if an error occurs when finding the free space
- * @since 1.1, enhanced OS support in 1.2 and 1.3
- * @deprecated Use freeSpaceKb(String)
- * Deprecated from 1.3, may be removed in 2.0
- */
- @Deprecated
- public static long freeSpace(String path) throws IOException {
- return INSTANCE.freeSpaceOS(path, OS, false, -1);
- }
- //-----------------------------------------------------------------------
- /**
- * Returns the free space on a drive or volume in kilobytes by invoking
- * the command line.
- * <pre>
- * FileSystemUtils.freeSpaceKb("C:"); // Windows
- * FileSystemUtils.freeSpaceKb("/volume"); // *nix
- * </pre>
- * The free space is calculated via the command line.
- * It uses 'dir /-c' on Windows, 'df -kP' on AIX/HP-UX and 'df -k' on other Unix.
- * <p>
- * In order to work, you must be running Windows, or have a implementation of
- * Unix df that supports GNU format when passed -k (or -kP). If you are going
- * to rely on this code, please check that it works on your OS by running
- * some simple tests to compare the command line with the output from this class.
- * If your operating system isn't supported, please raise a JIRA call detailing
- * the exact result from df -k and as much other detail as possible, thanks.
- *
- * @param path the path to get free space for, not null, not empty on Unix
- * @return the amount of free drive space on the drive or volume in kilobytes
- * @throws IllegalArgumentException if the path is invalid
- * @throws IllegalStateException if an error occurred in initialisation
- * @throws IOException if an error occurs when finding the free space
- * @since 1.2, enhanced OS support in 1.3
- */
- public static long freeSpaceKb(String path) throws IOException {
- return freeSpaceKb(path, -1);
- }
- /**
- * Returns the free space on a drive or volume in kilobytes by invoking
- * the command line.
- * <pre>
- * FileSystemUtils.freeSpaceKb("C:"); // Windows
- * FileSystemUtils.freeSpaceKb("/volume"); // *nix
- * </pre>
- * The free space is calculated via the command line.
- * It uses 'dir /-c' on Windows, 'df -kP' on AIX/HP-UX and 'df -k' on other Unix.
- * <p>
- * In order to work, you must be running Windows, or have a implementation of
- * Unix df that supports GNU format when passed -k (or -kP). If you are going
- * to rely on this code, please check that it works on your OS by running
- * some simple tests to compare the command line with the output from this class.
- * If your operating system isn't supported, please raise a JIRA call detailing
- * the exact result from df -k and as much other detail as possible, thanks.
- *
- * @param path the path to get free space for, not null, not empty on Unix
- * @param timeout The timout amount in milliseconds or no timeout if the value
- * is zero or less
- * @return the amount of free drive space on the drive or volume in kilobytes
- * @throws IllegalArgumentException if the path is invalid
- * @throws IllegalStateException if an error occurred in initialisation
- * @throws IOException if an error occurs when finding the free space
- * @since 2.0
- */
- public static long freeSpaceKb(String path, long timeout) throws IOException {
- return INSTANCE.freeSpaceOS(path, OS, true, timeout);
- }
- /**
- * Returns the disk size of the volume which holds the working directory.
- * <p>
- * Identical to:
- * <pre>
- * freeSpaceKb(new File(".").getAbsolutePath())
- * </pre>
- * @return the amount of free drive space on the drive or volume in kilobytes
- * @throws IllegalStateException if an error occurred in initialisation
- * @throws IOException if an error occurs when finding the free space
- * @since 2.0
- */
- public static long freeSpaceKb() throws IOException {
- return freeSpaceKb(-1);
- }
- /**
- * Returns the disk size of the volume which holds the working directory.
- * <p>
- * Identical to:
- * <pre>
- * freeSpaceKb(new File(".").getAbsolutePath())
- * </pre>
- * @param timeout The timout amount in milliseconds or no timeout if the value
- * is zero or less
- * @return the amount of free drive space on the drive or volume in kilobytes
- * @throws IllegalStateException if an error occurred in initialisation
- * @throws IOException if an error occurs when finding the free space
- * @since 2.0
- */
- public static long freeSpaceKb(long timeout) throws IOException {
- return freeSpaceKb(new File(".").getAbsolutePath(), timeout);
- }
-
- //-----------------------------------------------------------------------
- /**
- * Returns the free space on a drive or volume in a cross-platform manner.
- * Note that some OS's are NOT currently supported, including OS/390.
- * <pre>
- * FileSystemUtils.freeSpace("C:"); // Windows
- * FileSystemUtils.freeSpace("/volume"); // *nix
- * </pre>
- * The free space is calculated via the command line.
- * It uses 'dir /-c' on Windows and 'df' on *nix.
- *
- * @param path the path to get free space for, not null, not empty on Unix
- * @param os the operating system code
- * @param kb whether to normalize to kilobytes
- * @param timeout The timout amount in milliseconds or no timeout if the value
- * is zero or less
- * @return the amount of free drive space on the drive or volume
- * @throws IllegalArgumentException if the path is invalid
- * @throws IllegalStateException if an error occurred in initialisation
- * @throws IOException if an error occurs when finding the free space
- */
- long freeSpaceOS(String path, int os, boolean kb, long timeout) throws IOException {
- if (path == null) {
- throw new IllegalArgumentException("Path must not be empty");
- }
- switch (os) {
- case WINDOWS:
- return kb ? freeSpaceWindows(path, timeout) / FileUtils.ONE_KB : freeSpaceWindows(path, timeout);
- case UNIX:
- return freeSpaceUnix(path, kb, false, timeout);
- case POSIX_UNIX:
- return freeSpaceUnix(path, kb, true, timeout);
- case OTHER:
- throw new IllegalStateException("Unsupported operating system");
- default:
- throw new IllegalStateException(
- "Exception caught when determining operating system");
- }
- }
- //-----------------------------------------------------------------------
- /**
- * Find free space on the Windows platform using the 'dir' command.
- *
- * @param path the path to get free space for, including the colon
- * @param timeout The timout amount in milliseconds or no timeout if the value
- * is zero or less
- * @return the amount of free drive space on the drive
- * @throws IOException if an error occurs
- */
- long freeSpaceWindows(String path, long timeout) throws IOException {
- path = FilenameUtils.normalize(path, false);
- if (path.length() > 0 && path.charAt(0) != '"') {
- path = "\"" + path + "\"";
- }
-
- // build and run the 'dir' command
- String[] cmdAttribs = new String[] {"cmd.exe", "/C", "dir /a /-c " + path};
-
- // read in the output of the command to an ArrayList
- List<String> lines = performCommand(cmdAttribs, Integer.MAX_VALUE, timeout);
-
- // now iterate over the lines we just read and find the LAST
- // non-empty line (the free space bytes should be in the last element
- // of the ArrayList anyway, but this will ensure it works even if it's
- // not, still assuming it is on the last non-blank line)
- for (int i = lines.size() - 1; i >= 0; i--) {
- String line = lines.get(i);
- if (line.length() > 0) {
- return parseDir(line, path);
- }
- }
- // all lines are blank
- throw new IOException(
- "Command line 'dir /-c' did not return any info " +
- "for path '" + path + "'");
- }
- /**
- * Parses the Windows dir response last line
- *
- * @param line the line to parse
- * @param path the path that was sent
- * @return the number of bytes
- * @throws IOException if an error occurs
- */
- long parseDir(String line, String path) throws IOException {
- // read from the end of the line to find the last numeric
- // character on the line, then continue until we find the first
- // non-numeric character, and everything between that and the last
- // numeric character inclusive is our free space bytes count
- int bytesStart = 0;
- int bytesEnd = 0;
- int j = line.length() - 1;
- innerLoop1: while (j >= 0) {
- char c = line.charAt(j);
- if (Character.isDigit(c)) {
- // found the last numeric character, this is the end of
- // the free space bytes count
- bytesEnd = j + 1;
- break innerLoop1;
- }
- j--;
- }
- innerLoop2: while (j >= 0) {
- char c = line.charAt(j);
- if (!Character.isDigit(c) && c != ',' && c != '.') {
- // found the next non-numeric character, this is the
- // beginning of the free space bytes count
- bytesStart = j + 1;
- break innerLoop2;
- }
- j--;
- }
- if (j < 0) {
- throw new IOException(
- "Command line 'dir /-c' did not return valid info " +
- "for path '" + path + "'");
- }
-
- // remove commas and dots in the bytes count
- StringBuilder buf = new StringBuilder(line.substring(bytesStart, bytesEnd));
- for (int k = 0; k < buf.length(); k++) {
- if (buf.charAt(k) == ',' || buf.charAt(k) == '.') {
- buf.deleteCharAt(k--);
- }
- }
- return parseBytes(buf.toString(), path);
- }
- //-----------------------------------------------------------------------
- /**
- * Find free space on the *nix platform using the 'df' command.
- *
- * @param path the path to get free space for
- * @param kb whether to normalize to kilobytes
- * @param posix whether to use the posix standard format flag
- * @param timeout The timout amount in milliseconds or no timeout if the value
- * is zero or less
- * @return the amount of free drive space on the volume
- * @throws IOException if an error occurs
- */
- long freeSpaceUnix(String path, boolean kb, boolean posix, long timeout) throws IOException {
- if (path.length() == 0) {
- throw new IllegalArgumentException("Path must not be empty");
- }
- // build and run the 'dir' command
- String flags = "-";
- if (kb) {
- flags += "k";
- }
- if (posix) {
- flags += "P";
- }
- String[] cmdAttribs =
- flags.length() > 1 ? new String[] {DF, flags, path} : new String[] {DF, path};
-
- // perform the command, asking for up to 3 lines (header, interesting, overflow)
- List<String> lines = performCommand(cmdAttribs, 3, timeout);
- if (lines.size() < 2) {
- // unknown problem, throw exception
- throw new IOException(
- "Command line '" + DF + "' did not return info as expected " +
- "for path '" + path + "'- response was " + lines);
- }
- String line2 = lines.get(1); // the line we're interested in
-
- // Now, we tokenize the string. The fourth element is what we want.
- StringTokenizer tok = new StringTokenizer(line2, " ");
- if (tok.countTokens() < 4) {
- // could be long Filesystem, thus data on third line
- if (tok.countTokens() == 1 && lines.size() >= 3) {
- String line3 = lines.get(2); // the line may be interested in
- tok = new StringTokenizer(line3, " ");
- } else {
- throw new IOException(
- "Command line '" + DF + "' did not return data as expected " +
- "for path '" + path + "'- check path is valid");
- }
- } else {
- tok.nextToken(); // Ignore Filesystem
- }
- tok.nextToken(); // Ignore 1K-blocks
- tok.nextToken(); // Ignore Used
- String freeSpace = tok.nextToken();
- return parseBytes(freeSpace, path);
- }
- //-----------------------------------------------------------------------
- /**
- * Parses the bytes from a string.
- *
- * @param freeSpace the free space string
- * @param path the path
- * @return the number of bytes
- * @throws IOException if an error occurs
- */
- long parseBytes(String freeSpace, String path) throws IOException {
- try {
- long bytes = Long.parseLong(freeSpace);
- if (bytes < 0) {
- throw new IOException(
- "Command line '" + DF + "' did not find free space in response " +
- "for path '" + path + "'- check path is valid");
- }
- return bytes;
-
- } catch (NumberFormatException ex) {
- throw new IOExceptionWithCause(
- "Command line '" + DF + "' did not return numeric data as expected " +
- "for path '" + path + "'- check path is valid", ex);
- }
- }
- //-----------------------------------------------------------------------
- /**
- * Performs the os command.
- *
- * @param cmdAttribs the command line parameters
- * @param max The maximum limit for the lines returned
- * @param timeout The timout amount in milliseconds or no timeout if the value
- * is zero or less
- * @return the parsed data
- * @throws IOException if an error occurs
- */
- List<String> performCommand(String[] cmdAttribs, int max, long timeout) throws IOException {
- // this method does what it can to avoid the 'Too many open files' error
- // based on trial and error and these links:
- // http://bugs.sun.com/bugdatabase/view_bug.do?bug_id=4784692
- // http://bugs.sun.com/bugdatabase/view_bug.do?bug_id=4801027
- // http://forum.java.sun.com/thread.jspa?threadID=533029&messageID=2572018
- // however, its still not perfect as the JDK support is so poor
- // (see commond-exec or ant for a better multi-threaded multi-os solution)
-
- List<String> lines = new ArrayList<String>(20);
- Process proc = null;
- InputStream in = null;
- OutputStream out = null;
- InputStream err = null;
- BufferedReader inr = null;
- try {
- Thread monitor = ThreadMonitor.start(timeout);
- proc = openProcess(cmdAttribs);
- in = proc.getInputStream();
- out = proc.getOutputStream();
- err = proc.getErrorStream();
- inr = new BufferedReader(new InputStreamReader(in));
- String line = inr.readLine();
- while (line != null && lines.size() < max) {
- line = line.toLowerCase(Locale.ENGLISH).trim();
- lines.add(line);
- line = inr.readLine();
- }
-
- proc.waitFor();
- ThreadMonitor.stop(monitor);
- if (proc.exitValue() != 0) {
- // os command problem, throw exception
- throw new IOException(
- "Command line returned OS error code '" + proc.exitValue() +
- "' for command " + Arrays.asList(cmdAttribs));
- }
- if (lines.isEmpty()) {
- // unknown problem, throw exception
- throw new IOException(
- "Command line did not return any info " +
- "for command " + Arrays.asList(cmdAttribs));
- }
- return lines;
-
- } catch (InterruptedException ex) {
- throw new IOExceptionWithCause(
- "Command line threw an InterruptedException " +
- "for command " + Arrays.asList(cmdAttribs) + " timeout=" + timeout, ex);
- } finally {
- IOUtils.closeQuietly(in);
- IOUtils.closeQuietly(out);
- IOUtils.closeQuietly(err);
- IOUtils.closeQuietly(inr);
- if (proc != null) {
- proc.destroy();
- }
- }
- }
- /**
- * Opens the process to the operating system.
- *
- * @param cmdAttribs the command line parameters
- * @return the process
- * @throws IOException if an error occurs
- */
- Process openProcess(String[] cmdAttribs) throws IOException {
- return Runtime.getRuntime().exec(cmdAttribs);
- }
- }