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package panda.io;
import java.io.BufferedOutputStream;
import java.io.Closeable;
import java.io.File;
import java.io.FileFilter;
import java.io.FileInputStream;
import java.io.FileNotFoundException;
import java.io.FileOutputStream;
import java.io.IOException;
import java.io.InputStream;
import java.io.InputStreamReader;
import java.io.OutputStream;
import java.io.RandomAccessFile;
import java.io.Reader;
import java.io.UnsupportedEncodingException;
import java.math.BigInteger;
import java.net.URL;
import java.net.URLConnection;
import java.nio.ByteBuffer;
import java.nio.channels.FileChannel;
import java.nio.channels.FileLock;
import java.nio.channels.OverlappingFileLockException;
import java.nio.charset.Charset;
import java.nio.charset.UnsupportedCharsetException;
import java.util.ArrayList;
import java.util.Collection;
import java.util.Date;
import java.util.List;
import java.util.zip.CRC32;
import java.util.zip.CheckedInputStream;
import java.util.zip.Checksum;
import panda.io.filter.IOFileFilter;
import panda.io.stream.BOMInputStream;
import panda.lang.Charsets;
import panda.lang.Iterators;
import panda.lang.Numbers;
import panda.lang.Systems;
/**
* File Utilities class.
*
*/
public class Files {
/**
* An empty array of type File.
*/
public static final File[] EMPTY_FILE_ARRAY = new File[0];
/**
* The file copy buffer size (30 MB)
*/
private static final long FILE_COPY_BUFFER_SIZE = Numbers.MB * 30;
public static class FileLocker implements Closeable {
RandomAccessFile file;
FileLock lock;
public FileLocker(RandomAccessFile file, FileLock lock) {
this.file = file;
this.lock = lock;
}
@Override
public void close() throws IOException {
if (lock != null) {
lock.release();
}
file.close();
}
}
/**
* lock file
* @param file the File object
* @return the FileLocker
* @throws IOException if an IO error occurs
*/
public static FileLocker lock(File file) throws IOException {
RandomAccessFile raf = new RandomAccessFile(file, "rw");
// Get a file channel for the file
FileChannel channel = raf.getChannel();
// Use the file channel to create a lock on the file.
// This method blocks until it can retrieve the lock.
FileLock lock = channel.lock();
return new FileLocker(raf, lock);
}
/**
* try to lock file
* @param file the File object
* @return the FileLocker
* @throws IOException if an IO error occurs
*/
public static FileLocker tryLock(File file) throws IOException {
RandomAccessFile raf = new RandomAccessFile(file, "rw");
// Get a file channel for the file
FileChannel channel = raf.getChannel();
// Try acquiring the lock without blocking. This method returns
// null or throws an exception if the file is already locked.
try {
FileLock lock = channel.tryLock();
return new FileLocker(raf, lock);
}
catch (OverlappingFileLockException e) {
// File is already locked in this thread or virtual machine
raf.close();
return null;
}
}
/**
* copy file or directory
*
* @param src source file or directory
* @param des target file or directory
* @throws IOException if an IO error occurs
*/
public static void copy(File src, File des) throws IOException {
if (src.isDirectory()) {
copyDir(src, des);
}
else {
copyFile(src, des);
}
}
/**
* existence check
*
* @param file the file name
* @return false if file is null or not exists
*/
public static boolean exists(String file) {
return null != file && new File(file).exists();
}
/**
* existence check
*
* @param file the File object
* @return false if file is null or not exists
*/
public static boolean exists(File file) {
return null != file && file.exists();
}
/**
* directory check
*
* @param dir the directory name
* @return false if file is null or not directory
*/
public static boolean isDirectory(String dir) {
return null != dir && isDirectory(new File(dir));
}
/**
* directory check
*
* @param dir the File object
* @return false if file is null or not directory
*/
public static boolean isDirectory(File dir) {
return null != dir && dir.exists() && dir.isDirectory();
}
/**
* file check
*
* @param f the file name
* @return false if file is null or not file
*/
public static boolean isFile(String f) {
return null != f && isFile(new File(f));
}
/**
* file check
*
* @param f the File object
* @return false if file is null or not file
*/
public static boolean isFile(File f) {
return null != f && f.exists() && f.isFile();
}
/**
* create a file. If the parent folder does not exist, the parent folder will be created.
*
* @param file file
* @return false if file already exists or failed to create, true if created successfully
* @throws IOException if an IO error occurs
*/
public static boolean createFile(File file) throws IOException {
if (null == file || file.exists()) {
return false;
}
makeDirs(file.getParentFile());
return file.createNewFile();
}
// -----------------------------------------------------------------------
/**
* Construct a file from the set of name elements.
*
* @param directory the parent directory
* @param names the name elements
* @return the file
*/
public static File getFile(final File directory, final String... names) {
if (directory == null) {
throw new NullPointerException("directorydirectory must not be null");
}
if (names == null) {
throw new NullPointerException("names must not be null");
}
File file = directory;
for (final String name : names) {
file = new File(file, name);
}
return file;
}
/**
* Construct a file from the set of name elements.
*
* @param names the name elements
* @return the file
*/
public static File getFile(final String... names) {
if (names == null) {
throw new NullPointerException("names must not be null");
}
File file = null;
for (final String name : names) {
if (file == null) {
file = new File(name);
}
else {
file = new File(file, name);
}
}
return file;
}
/**
* Returns the path to the system temporary directory.
*
* @return the path to the system temporary directory.
*/
public static String getTempDirectoryPath() {
return Systems.JAVA_IO_TMPDIR;
}
/**
* Returns a {@link File} representing the system temporary directory.
*
* @return the system temporary directory.
*/
public static File getTempDirectory() {
return Systems.getJavaIoTmpDir();
}
/**
* Returns the path to the user's home directory.
*
* @return the path to the user's home directory.
*/
public static String getUserDirectoryPath() {
return System.getProperty("user.home");
}
/**
* Returns a {@link File} representing the user's home directory.
*
* @return the user's home directory.
*/
public static File getUserDirectory() {
return new File(getUserDirectoryPath());
}
// -----------------------------------------------------------------------
/**
* Implements the same behaviour as the "touch" utility on Unix. It creates a new file with size
* 0 or, if the file exists already, it is opened and closed without modifying it, but updating
* the file date and time.
*
* NOTE: this method throws an IOException if the last modified date of the file
* cannot be set. Also, this method creates parent directories if they do not
* exist.
*
* @param file the File to touch
* @throws IOException If an I/O problem occurs
*/
public static void touch(final File file) throws IOException {
if (!file.exists()) {
final OutputStream out = Streams.openOutputStream(file);
Streams.safeClose(out);
}
final boolean success = file.setLastModified(System.currentTimeMillis());
if (!success) {
throw new IOException("Unable to set the last modification time for " + file);
}
}
// -----------------------------------------------------------------------
/**
* Converts a Collection containing java.io.File instanced into array representation. This is to
* account for the difference between File.listFiles() and FileUtils.listFiles().
*
* @param files a Collection containing java.io.File instances
* @return an array of java.io.File
*/
public static File[] convertFileCollectionToFileArray(final Collection files) {
return files.toArray(new File[files.size()]);
}
// -----------------------------------------------------------------------
private static List fileIteratorToList(FileIterator it) {
try {
return Iterators.toList(it);
}
finally {
Streams.safeClose(it);
}
}
/**
* Finds files within a given directory (no sub directories) which match an array
* of extensions.
*
* @param directory the directory to search in
* @param extensions an array of extensions, ex. {"java","xml"}. If this parameter is
* {@code null}, all files are returned.
* @return an collection of java.io.File with the matching files
*/
public static List listFiles(File directory, String... extensions) {
return fileIteratorToList(iterateFiles(directory, extensions));
}
/**
* Finds files within a given directory (and optionally its sub directories) which match an array
* of extensions.
*
* @param directory the directory to search in
* @param extensions an array of extensions, ex. {"java","xml"}. If this parameter is
* {@code null}, all files are returned.
* @param recursive if true all sub directories are searched as well
* @return an collection of java.io.File with the matching files
*/
public static List listFiles(File directory, boolean recursive, String... extensions) {
return fileIteratorToList(iterateFiles(directory, recursive, extensions));
}
/**
* Finds files within a given directory (and optionally its sub directories). All files found are
* filtered by an IOFileFilter.
*
* If your search should recurse into sub directories you can pass in an IOFileFilter for
* directories. You don't need to bind a DirectoryFileFilter (via logical AND) to this filter.
* This method does that for you.
*
* An example: If you want to search through all directories called "temp" you pass in
* FileFilters.NameFileFilter("temp")
*
* Another common usage of this method is find files in a directory tree but ignoring the
* directories generated CVS. You can simply pass in
* FileFilters.makeCVSAware(null).
*
* @param directory the directory to search in
* @param recursive if true all sub directories are searched as well
* @param fileFilter filter to apply when finding files.
* @return an collection of java.io.File with the matching files
* @see panda.io.filter.FileFilters
* @see panda.io.filter.NameFileFilter
*/
public static List listFiles(File directory, boolean recursive, IOFileFilter fileFilter) {
return fileIteratorToList(iterateFiles(directory, recursive, fileFilter));
}
/**
* Finds files within a given directory (and optionally its sub directories). All files found are
* filtered by an IOFileFilter.
*
* If your search should recurse into sub directories you can pass in an IOFileFilter for
* directories. You don't need to bind a DirectoryFileFilter (via logical AND) to this filter.
* This method does that for you.
*
* An example: If you want to search through all directories called "temp" you pass in
* FileFilters.NameFileFilter("temp")
*
* Another common usage of this method is find files in a directory tree but ignoring the
* directories generated CVS. You can simply pass in
* FileFilters.makeCVSAware(null).
*
* @param directory the directory to search in
* @param fileFilter filter to apply when finding files.
* @param dirFilter optional filter to apply when finding sub directories. If this parameter is
* {@code null}, sub directories will not be included in the search. Use
* TrueFileFilter.INSTANCE to match all directories.
* @return an collection of java.io.File with the matching files
* @see panda.io.filter.FileFilters
* @see panda.io.filter.NameFileFilter
*/
public static List listFiles(File directory, IOFileFilter fileFilter, IOFileFilter dirFilter) {
return fileIteratorToList(iterateFiles(directory, fileFilter, dirFilter));
}
/**
* Finds files within a given directory (and optionally its sub directories). All files found are
* filtered by an IOFileFilter.
*
* The resulting collection includes the sub directories themselves.
*
*
* @see Files#listFiles
* @param directory the directory to search in
* @param fileFilter filter to apply when finding files.
* @param dirFilter optional filter to apply when finding sub directories. If this parameter is
* {@code null}, sub directories will not be included in the search. Use
* TrueFileFilter.INSTANCE to match all directories.
* @return an collection of java.io.File with the matching files
* @see panda.io.filter.FileFilters
* @see panda.io.filter.NameFileFilter
*/
public static List listFilesAndDirs(File directory, IOFileFilter fileFilter, IOFileFilter dirFilter) {
return fileIteratorToList(iterateFilesAndDirs(directory, fileFilter, dirFilter));
}
// -----------------------------------------------------------------------
/**
* Allows iteration over the files in a given directory (no recursive)
* which match an array of extensions.
*
* @param directory the directory to search in
* @param extensions an array of extensions, ex. {"java","xml"}. If this parameter is
* {@code null}, all files are returned.
* @return an iterator of java.io.File with the matching files
*/
public static FileIterator iterateFiles(File directory, String... extensions) {
if (Systems.IS_OS_APPENGINE) {
return new IOFileIterator(directory, extensions);
}
return new NioFileIterator(directory, extensions);
}
/**
* Allows iteration over the files in a given directory (and optionally its sub directories)
* which match an array of extensions.
*
* @param directory the directory to search in
* @param extensions an array of extensions, ex. {"java","xml"}. If this parameter is
* {@code null}, all files are returned.
* @param recursive if true all sub directories are searched as well
* @return an iterator of java.io.File with the matching files
*/
public static FileIterator iterateFiles(File directory, boolean recursive, String... extensions) {
if (Systems.IS_OS_APPENGINE) {
return new IOFileIterator(directory, recursive, extensions);
}
return new NioFileIterator(directory, recursive, extensions);
}
/**
* Allows iteration over the files in given directory (and optionally its sub directories).
*
* All files found are filtered by an IOFileFilter.
*
*
* @param directory the directory to search in
* @param recursive if true all sub directories are searched as well
* @param fileFilter filter to apply when finding files.
* @return an iterator of java.io.File for the matching files
* @see panda.io.filter.FileFilters
* @see panda.io.filter.NameFileFilter
*/
public static FileIterator iterateFiles(File directory, boolean recursive, IOFileFilter fileFilter) {
if (Systems.IS_OS_APPENGINE) {
return new IOFileIterator(directory, recursive, fileFilter);
}
return new NioFileIterator(directory, recursive, fileFilter);
}
/**
* Allows iteration over the files in given directory (and optionally its sub directories).
*
* All files found are filtered by an IOFileFilter.
*
*
* @param directory the directory to search in
* @param fileFilter filter to apply when finding files.
* @param dirFilter optional filter to apply when finding sub directories. If this parameter is
* {@code null}, sub directories will not be included in the search. Use
* TrueFileFilter.INSTANCE to match all directories.
* @return an iterator of java.io.File for the matching files
* @see panda.io.filter.FileFilters
* @see panda.io.filter.NameFileFilter
*/
public static FileIterator iterateFiles(File directory, IOFileFilter fileFilter, IOFileFilter dirFilter) {
if (Systems.IS_OS_APPENGINE) {
return new IOFileIterator(directory, fileFilter, dirFilter);
}
return new NioFileIterator(directory, fileFilter, dirFilter);
}
/**
* Allows iteration over the files in given directory (and optionally its sub directories).
*
* All files found are filtered by an IOFileFilter.
*
* The resulting iterator includes the sub directories themselves.
*
* @param directory the directory to search in
* @param fileFilter filter to apply when finding files.
* @param dirFilter optional filter to apply when finding sub directories. If this parameter is
* {@code null}, sub directories will not be included in the search. Use
* TrueFileFilter.INSTANCE to match all directories.
* @return an iterator of java.io.File for the matching files
* @see panda.io.filter.FileFilters
* @see panda.io.filter.NameFileFilter
*/
public static FileIterator iterateFilesAndDirs(File directory, IOFileFilter fileFilter, IOFileFilter dirFilter) {
if (Systems.IS_OS_APPENGINE) {
return new IOFileIterator(directory, fileFilter, dirFilter, true);
}
return new NioFileIterator(directory, fileFilter, dirFilter, true);
}
// -----------------------------------------------------------------------
/**
* Compares the contents of two files to determine if they are equal or not.
*
* This method checks to see if the two files are different lengths or if they point to the same
* file, before resorting to byte-by-byte comparison of the contents.
*
* Code origin: Avalon
*
* @param file1 the first file
* @param file2 the second file
* @return true if the content of the files are equal or they both don't exist, false otherwise
* @throws IOException in case of an I/O error
*/
public static boolean contentEquals(final File file1, final File file2) throws IOException {
final boolean file1Exists = file1.exists();
if (file1Exists != file2.exists()) {
return false;
}
if (!file1Exists) {
// two not existing files are equal
return true;
}
if (file1.isDirectory() || file2.isDirectory()) {
// don't want to compare directory contents
throw new IOException("Can't compare directories, only files");
}
if (file1.length() != file2.length()) {
// lengths differ, cannot be equal
return false;
}
if (file1.getCanonicalFile().equals(file2.getCanonicalFile())) {
// same file
return true;
}
InputStream input1 = null;
InputStream input2 = null;
try {
input1 = new FileInputStream(file1);
input2 = new FileInputStream(file2);
return Streams.contentEquals(input1, input2);
}
finally {
Streams.safeClose(input1);
Streams.safeClose(input2);
}
}
// -----------------------------------------------------------------------
/**
* Compares the contents of two files to determine if they are equal or not.
*
* This method checks to see if the two files point to the same file, before resorting to
* line-by-line comparison of the contents.
*
*
* @param file1 the first file
* @param file2 the second file
* @param charsetName the character encoding to be used. May be null, in which case the platform
* default is used
* @return true if the content of the files are equal or neither exists, false otherwise
* @throws IOException in case of an I/O error
* @see Streams#contentEqualsIgnoreEOL(Reader, Reader)
*/
public static boolean contentEqualsIgnoreEOL(final File file1, final File file2, final String charsetName)
throws IOException {
final boolean file1Exists = file1.exists();
if (file1Exists != file2.exists()) {
return false;
}
if (!file1Exists) {
// two not existing files are equal
return true;
}
if (file1.isDirectory() || file2.isDirectory()) {
// don't want to compare directory contents
throw new IOException("Can't compare directories, only files");
}
if (file1.getCanonicalFile().equals(file2.getCanonicalFile())) {
// same file
return true;
}
Reader input1 = null;
Reader input2 = null;
try {
if (charsetName == null) {
input1 = new InputStreamReader(new FileInputStream(file1));
input2 = new InputStreamReader(new FileInputStream(file2));
}
else {
input1 = new InputStreamReader(new FileInputStream(file1), charsetName);
input2 = new InputStreamReader(new FileInputStream(file2), charsetName);
}
return Streams.contentEqualsIgnoreEOL(input1, input2);
}
finally {
Streams.safeClose(input1);
Streams.safeClose(input2);
}
}
// -----------------------------------------------------------------------
/**
* Convert from a URL to a File.
*
* From version 1.1 this method will decode the URL. Syntax such as
* file:///my%20docs/file.txt will be correctly decoded to
* /my docs/file.txt. Starting with version 1.5, this method uses UTF-8 to decode
* percent-encoded octets to characters. Additionally, malformed percent-encoded octets are
* handled leniently by passing them through literally.
*
* @param url the file URL to convert, {@code null} returns {@code null}
* @return the equivalent File object, or {@code null} if the URL's protocol is not
* file
*/
public static File toFile(final URL url) {
if (url == null || !"file".equalsIgnoreCase(url.getProtocol())) {
return null;
}
else {
String filename = url.getFile().replace('/', File.separatorChar);
filename = decodeUrl(filename);
return new File(filename);
}
}
/**
* Decodes the specified URL as per RFC 3986, i.e. transforms percent-encoded octets to
* characters by decoding with the UTF-8 character set. This function is primarily intended for
* usage with {@link java.net.URL} which unfortunately does not enforce proper URLs. As such,
* this method will leniently accept invalid characters or malformed percent-encoded octets and
* simply pass them literally through to the result string. Except for rare edge cases, this
* will make unencoded URLs pass through unaltered.
*
* @param url The URL to decode, may be {@code null}.
* @return The decoded URL or {@code null} if the input was {@code null}.
*/
static String decodeUrl(final String url) {
String decoded = url;
if (url != null && url.indexOf('%') >= 0) {
final int n = url.length();
final StringBuilder buffer = new StringBuilder();
final ByteBuffer bytes = ByteBuffer.allocate(n);
for (int i = 0; i < n;) {
if (url.charAt(i) == '%') {
try {
do {
final byte octet = (byte)Integer.parseInt(url.substring(i + 1, i + 3), 16);
bytes.put(octet);
i += 3;
}
while (i < n && url.charAt(i) == '%');
continue;
}
catch (final RuntimeException e) {
// malformed percent-encoded octet, fall through and
// append characters literally
}
finally {
if (bytes.position() > 0) {
bytes.flip();
buffer.append(Charsets.CS_UTF_8.decode(bytes).toString());
bytes.clear();
}
}
}
buffer.append(url.charAt(i++));
}
decoded = buffer.toString();
}
return decoded;
}
/**
* Converts each of an array of URL to a File.
*
* Returns an array of the same size as the input. If the input is {@code null}, an empty array
* is returned. If the input contains {@code null}, the output array contains {@code null} at
* the same index.
*
* This method will decode the URL. Syntax such as file:///my%20docs/file.txt will
* be correctly decoded to /my docs/file.txt.
*
* @param urls the file URLs to convert, {@code null} returns empty array
* @return a non-{@code null} array of Files matching the input, with a {@code null} item if
* there was a {@code null} at that index in the input array
* @throws IllegalArgumentException if any file is not a URL file
* @throws IllegalArgumentException if any file is incorrectly encoded
*/
public static File[] toFiles(final URL[] urls) {
if (urls == null || urls.length == 0) {
return EMPTY_FILE_ARRAY;
}
final File[] files = new File[urls.length];
for (int i = 0; i < urls.length; i++) {
final URL url = urls[i];
if (url != null) {
if (url.getProtocol().equals("file") == false) {
throw new IllegalArgumentException("URL could not be converted to a File: " + url);
}
files[i] = toFile(url);
}
}
return files;
}
/**
* Converts each of an array of File to a URL.
*
* Returns an array of the same size as the input.
*
* @param files the files to convert, must not be {@code null}
* @return an array of URLs matching the input
* @throws IOException if a file cannot be converted
* @throws NullPointerException if the parameter is null
*/
public static URL[] toURLs(final File[] files) throws IOException {
final URL[] urls = new URL[files.length];
for (int i = 0; i < urls.length; i++) {
urls[i] = files[i].toURI().toURL();
}
return urls;
}
// -----------------------------------------------------------------------
/**
* Copies a file to a directory preserving the file date.
*
* This method copies the contents of the specified source file to a file of the same name in
* the specified destination directory. The destination directory is created if it does not
* exist. If the destination file exists, then this method will overwrite it.
*
* Note: This method tries to preserve the file's last modified date/times
* using {@link File#setLastModified(long)}, however it is not guaranteed that the operation
* will succeed. If the modification operation fails, no indication is provided.
*
* @param srcFile an existing file to copy, must not be {@code null}
* @param destDir the directory to place the copy in, must not be {@code null}
* @throws NullPointerException if source or destination is null
* @throws IOException if source or destination is invalid
* @throws IOException if an IO error occurs during copying
* @see #copyFile(File, File, boolean)
*/
public static void copyFileToDir(final File srcFile, final File destDir) throws IOException {
copyFileToDir(srcFile, destDir, true);
}
/**
* Copies a file to a directory optionally preserving the file date.
*
* This method copies the contents of the specified source file to a file of the same name in
* the specified destination directory. The destination directory is created if it does not
* exist. If the destination file exists, then this method will overwrite it.
*
* Note: Setting preserveFileDate to {@code true} tries to
* preserve the file's last modified date/times using {@link File#setLastModified(long)},
* however it is not guaranteed that the operation will succeed. If the modification operation
* fails, no indication is provided.
*
* @param srcFile an existing file to copy, must not be {@code null}
* @param destDir the directory to place the copy in, must not be {@code null}
* @param preserveFileDate true if the file date of the copy should be the same as the original
* @throws NullPointerException if source or destination is {@code null}
* @throws IOException if source or destination is invalid
* @throws IOException if an IO error occurs during copying
* @see #copyFile(File, File, boolean)
*/
public static void copyFileToDir(final File srcFile, final File destDir, final boolean preserveFileDate)
throws IOException {
if (destDir == null) {
throw new NullPointerException("Destination must not be null");
}
if (destDir.exists() && destDir.isDirectory() == false) {
throw new IllegalArgumentException("Destination '" + destDir + "' is not a directory");
}
final File destFile = new File(destDir, srcFile.getName());
copyFile(srcFile, destFile, preserveFileDate);
}
/**
* Copies a file to a new location preserving the file date.
*
* This method copies the contents of the specified source file to the specified destination
* file. The directory holding the destination file is created if it does not exist. If the
* destination file exists, then this method will overwrite it.
*
* Note: This method tries to preserve the file's last modified date/times
* using {@link File#setLastModified(long)}, however it is not guaranteed that the operation
* will succeed. If the modification operation fails, no indication is provided.
*
* @param srcFile an existing file to copy, must not be {@code null}
* @param destFile the new file, must not be {@code null}
* @throws NullPointerException if source or destination is {@code null}
* @throws IOException if source or destination is invalid
* @throws IOException if an IO error occurs during copying
* @see #copyFileToDir(File, File)
*/
public static void copyFile(final File srcFile, final File destFile) throws IOException {
copyFile(srcFile, destFile, true);
}
/**
* Copies a file to a new location.
*
* This method copies the contents of the specified source file to the specified destination
* file. The directory holding the destination file is created if it does not exist. If the
* destination file exists, then this method will overwrite it.
*
* Note: Setting preserveFileDate to {@code true} tries to
* preserve the file's last modified date/times using {@link File#setLastModified(long)},
* however it is not guaranteed that the operation will succeed. If the modification operation
* fails, no indication is provided.
*
* @param srcFile an existing file to copy, must not be {@code null}
* @param destFile the new file, must not be {@code null}
* @param preserveFileDate true if the file date of the copy should be the same as the original
* @throws NullPointerException if source or destination is {@code null}
* @throws IOException if source or destination is invalid
* @throws IOException if an IO error occurs during copying
* @see #copyFileToDir(File, File, boolean)
*/
public static void copyFile(final File srcFile, final File destFile, final boolean preserveFileDate)
throws IOException {
if (srcFile == null) {
throw new NullPointerException("Source must not be null");
}
if (destFile == null) {
throw new NullPointerException("Destination must not be null");
}
if (!srcFile.exists()) {
throw new FileNotFoundException("Source '" + srcFile + "' does not exist");
}
if (srcFile.isDirectory()) {
throw new IOException("Source '" + srcFile + "' exists but is a directory");
}
if (srcFile.getCanonicalPath().equals(destFile.getCanonicalPath())) {
throw new IOException("Source '" + srcFile + "' and destination '" + destFile + "' are the same");
}
final File parentFile = destFile.getParentFile();
if (parentFile != null) {
if (!parentFile.mkdirs() && !parentFile.isDirectory()) {
throw new IOException("Destination '" + parentFile + "' directory cannot be created");
}
}
if (destFile.exists() && destFile.canWrite() == false) {
throw new IOException("Destination '" + destFile + "' exists but is read-only");
}
doCopyFile(srcFile, destFile, preserveFileDate);
}
/**
* Copy bytes from a File to an OutputStream.
*
* This method buffers the input internally, so there is no need to use a
* BufferedInputStream.
*
*
* @param input the File to read from
* @param output the OutputStream to write to
* @return the number of bytes copied
* @throws NullPointerException if the input or output is null
* @throws IOException if an I/O error occurs
*/
public static long copyFile(final File input, final OutputStream output) throws IOException {
final FileInputStream fis = new FileInputStream(input);
try {
return Streams.copyLarge(fis, output);
}
finally {
fis.close();
}
}
/**
* Internal copy file method.
*
* @param srcFile the validated source file, must not be {@code null}
* @param destFile the validated destination file, must not be {@code null}
* @param preserveFileDate whether to preserve the file date
* @throws IOException if an error occurs
*/
private static void doCopyFile(final File srcFile, final File destFile, final boolean preserveFileDate)
throws IOException {
if (destFile.exists() && destFile.isDirectory()) {
throw new IOException("Destination '" + destFile + "' exists but is a directory");
}
FileInputStream fis = null;
FileOutputStream fos = null;
FileChannel input = null;
FileChannel output = null;
try {
fis = new FileInputStream(srcFile);
fos = new FileOutputStream(destFile);
input = fis.getChannel();
output = fos.getChannel();
final long size = input.size();
long pos = 0;
long count = 0;
while (pos < size) {
final long remain = size - pos;
count = remain > FILE_COPY_BUFFER_SIZE ? FILE_COPY_BUFFER_SIZE : remain;
final long bytesCopied = output.transferFrom(input, pos, count);
if (bytesCopied == 0) { // IO-385 - can happen if file is truncated after caching
// the size
break; // ensure we don't loop forever
}
pos += bytesCopied;
}
}
finally {
Streams.safeClose(output);
Streams.safeClose(fos);
Streams.safeClose(input);
Streams.safeClose(fis);
}
final long srcLen = srcFile.length();
final long dstLen = destFile.length();
if (srcLen != dstLen) {
throw new IOException("Failed to copy full contents from '" + srcFile + "' to '" + destFile
+ "' Expected length: " + srcLen + " Actual: " + dstLen);
}
if (preserveFileDate) {
destFile.setLastModified(srcFile.lastModified());
}
}
// -----------------------------------------------------------------------
/**
* Copies a directory to within another directory preserving the file dates.
*
* This method copies the source directory and all its contents to a directory of the same name
* in the specified destination directory.
*
* The destination directory is created if it does not exist. If the destination directory did
* exist, then this method merges the source with the destination, with the source taking
* precedence.
*
* Note: This method tries to preserve the files' last modified date/times
* using {@link File#setLastModified(long)}, however it is not guaranteed that those operations
* will succeed. If the modification operation fails, no indication is provided.
*
* @param srcDir an existing directory to copy, must not be {@code null}
* @param destDir the directory to place the copy in, must not be {@code null}
* @throws NullPointerException if source or destination is {@code null}
* @throws IOException if source or destination is invalid
* @throws IOException if an IO error occurs during copying
*/
public static void copyDirToDir(final File srcDir, final File destDir) throws IOException {
if (srcDir == null) {
throw new NullPointerException("Source must not be null");
}
if (srcDir.exists() && srcDir.isDirectory() == false) {
throw new IllegalArgumentException("Source '" + destDir + "' is not a directory");
}
if (destDir == null) {
throw new NullPointerException("Destination must not be null");
}
if (destDir.exists() && destDir.isDirectory() == false) {
throw new IllegalArgumentException("Destination '" + destDir + "' is not a directory");
}
copyDir(srcDir, new File(destDir, srcDir.getName()), true);
}
/**
* Copies a whole directory to a new location preserving the file dates.
*
* This method copies the specified directory and all its child directories and files to the
* specified destination. The destination is the new location and name of the directory.
*
* The destination directory is created if it does not exist. If the destination directory did
* exist, then this method merges the source with the destination, with the source taking
* precedence.
*
* Note: This method tries to preserve the files' last modified date/times
* using {@link File#setLastModified(long)}, however it is not guaranteed that those operations
* will succeed. If the modification operation fails, no indication is provided.
*
* @param srcDir an existing directory to copy, must not be {@code null}
* @param destDir the new directory, must not be {@code null}
* @throws NullPointerException if source or destination is {@code null}
* @throws IOException if source or destination is invalid
* @throws IOException if an IO error occurs during copying
*/
public static void copyDir(final File srcDir, final File destDir) throws IOException {
copyDir(srcDir, destDir, true);
}
/**
* Copies a whole directory to a new location.
*
* This method copies the contents of the specified source directory to within the specified
* destination directory.
*
* The destination directory is created if it does not exist. If the destination directory did
* exist, then this method merges the source with the destination, with the source taking
* precedence.
*
* Note: Setting preserveFileDate to {@code true} tries to
* preserve the files' last modified date/times using {@link File#setLastModified(long)},
* however it is not guaranteed that those operations will succeed. If the modification
* operation fails, no indication is provided.
*
* @param srcDir an existing directory to copy, must not be {@code null}
* @param destDir the new directory, must not be {@code null}
* @param preserveFileDate true if the file date of the copy should be the same as the original
* @throws NullPointerException if source or destination is {@code null}
* @throws IOException if source or destination is invalid
* @throws IOException if an IO error occurs during copying
*/
public static void copyDir(final File srcDir, final File destDir, final boolean preserveFileDate)
throws IOException {
copyDir(srcDir, destDir, null, preserveFileDate);
}
/**
* Copies a filtered directory to a new location preserving the file dates.
*
* This method copies the contents of the specified source directory to within the specified
* destination directory.
*
* The destination directory is created if it does not exist. If the destination directory did
* exist, then this method merges the source with the destination, with the source taking
* precedence.
*
* Note: This method tries to preserve the files' last modified date/times
* using {@link File#setLastModified(long)}, however it is not guaranteed that those operations
* will succeed. If the modification operation fails, no indication is provided.
*
Example: Copy directories only
*
*
* // only copy the directory structure
* FileUtils.copyDirectory(srcDir, destDir, DirectoryFileFilter.DIRECTORY);
*
*
* Example: Copy directories and txt files
*
*
* // Create a filter for ".txt" files
* IOFileFilter txtSuffixFilter = FileFilters.suffixFileFilter(".txt");
* IOFileFilter txtFiles = FileFilters.andFileFilter(FileFileFilter.FILE, txtSuffixFilter);
*
* // Create a filter for either directories or ".txt" files
* FileFilter filter = FileFilters.orFileFilter(DirectoryFileFilter.DIRECTORY, txtFiles);
*
* // Copy using the filter
* FileUtils.copyDirectory(srcDir, destDir, filter);
*
*
* @param srcDir an existing directory to copy, must not be {@code null}
* @param destDir the new directory, must not be {@code null}
* @param filter the filter to apply, null means copy all directories and files should be the
* same as the original
* @throws NullPointerException if source or destination is {@code null}
* @throws IOException if source or destination is invalid
* @throws IOException if an IO error occurs during copying
*/
public static void copyDir(final File srcDir, final File destDir, final FileFilter filter) throws IOException {
copyDir(srcDir, destDir, filter, true);
}
/**
* Copies a filtered directory to a new location.
*
* This method copies the contents of the specified source directory to within the specified
* destination directory.
*
* The destination directory is created if it does not exist. If the destination directory did
* exist, then this method merges the source with the destination, with the source taking
* precedence.
*
* Note: Setting preserveFileDate to {@code true} tries to
* preserve the files' last modified date/times using {@link File#setLastModified(long)},
* however it is not guaranteed that those operations will succeed. If the modification
* operation fails, no indication is provided.
*
Example: Copy directories only
*
*
* // only copy the directory structure
* FileUtils.copyDirectory(srcDir, destDir, DirectoryFileFilter.DIRECTORY, false);
*
*
* Example: Copy directories and txt files
*
*
* // Create a filter for ".txt" files
* IOFileFilter txtSuffixFilter = FileFilters.suffixFileFilter(".txt");
* IOFileFilter txtFiles = FileFilters.andFileFilter(FileFileFilter.FILE, txtSuffixFilter);
*
* // Create a filter for either directories or ".txt" files
* FileFilter filter = FileFilters.orFileFilter(DirectoryFileFilter.DIRECTORY, txtFiles);
*
* // Copy using the filter
* FileUtils.copyDirectory(srcDir, destDir, filter, false);
*
*
* @param srcDir an existing directory to copy, must not be {@code null}
* @param destDir the new directory, must not be {@code null}
* @param filter the filter to apply, null means copy all directories and files
* @param preserveFileDate true if the file date of the copy should be the same as the original
* @throws NullPointerException if source or destination is {@code null}
* @throws IOException if source or destination is invalid
* @throws IOException if an IO error occurs during copying
*/
public static void copyDir(final File srcDir, final File destDir, final FileFilter filter,
final boolean preserveFileDate) throws IOException {
if (srcDir == null) {
throw new NullPointerException("Source must not be null");
}
if (destDir == null) {
throw new NullPointerException("Destination must not be null");
}
if (srcDir.exists() == false) {
throw new FileNotFoundException("Source '" + srcDir + "' does not exist");
}
if (srcDir.isDirectory() == false) {
throw new IOException("Source '" + srcDir + "' exists but is not a directory");
}
if (srcDir.getCanonicalPath().equals(destDir.getCanonicalPath())) {
throw new IOException("Source '" + srcDir + "' and destination '" + destDir + "' are the same");
}
// Cater for destination being directory within the source directory (see IO-141)
List exclusionList = null;
if (destDir.getCanonicalPath().startsWith(srcDir.getCanonicalPath())) {
final File[] srcFiles = filter == null ? srcDir.listFiles() : srcDir.listFiles(filter);
if (srcFiles != null && srcFiles.length > 0) {
exclusionList = new ArrayList(srcFiles.length);
for (final File srcFile : srcFiles) {
final File copiedFile = new File(destDir, srcFile.getName());
exclusionList.add(copiedFile.getCanonicalPath());
}
}
}
doCopyDirectory(srcDir, destDir, filter, preserveFileDate, exclusionList);
}
/**
* Internal copy directory method.
*
* @param srcDir the validated source directory, must not be {@code null}
* @param destDir the validated destination directory, must not be {@code null}
* @param filter the filter to apply, null means copy all directories and files
* @param preserveFileDate whether to preserve the file date
* @param exclusionList List of files and directories to exclude from the copy, may be null
* @throws IOException if an error occurs
*/
private static void doCopyDirectory(final File srcDir, final File destDir, final FileFilter filter,
final boolean preserveFileDate, final List exclusionList) throws IOException {
// recurse
final File[] srcFiles = filter == null ? srcDir.listFiles() : srcDir.listFiles(filter);
if (srcFiles == null) { // null if abstract pathname does not denote a directory, or if an
// I/O error occurs
throw new IOException("Failed to list contents of " + srcDir);
}
if (destDir.exists()) {
if (destDir.isDirectory() == false) {
throw new IOException("Destination '" + destDir + "' exists but is not a directory");
}
}
else {
if (!destDir.mkdirs() && !destDir.isDirectory()) {
throw new IOException("Destination '" + destDir + "' directory cannot be created");
}
}
if (destDir.canWrite() == false) {
throw new IOException("Destination '" + destDir + "' cannot be written to");
}
for (final File srcFile : srcFiles) {
final File dstFile = new File(destDir, srcFile.getName());
if (exclusionList == null || !exclusionList.contains(srcFile.getCanonicalPath())) {
if (srcFile.isDirectory()) {
doCopyDirectory(srcFile, dstFile, filter, preserveFileDate, exclusionList);
}
else {
doCopyFile(srcFile, dstFile, preserveFileDate);
}
}
}
// Do this last, as the above has probably affected directory metadata
if (preserveFileDate) {
destDir.setLastModified(srcDir.lastModified());
}
}
// -----------------------------------------------------------------------
/**
* Copies bytes from the URL source to a file destination. The
* directories up to destination will be created if they don't already exist.
* destination will be overwritten if it already exists.
*
* Warning: this method does not set a connection or read timeout and thus might block forever.
* Use {@link #copyURLToFile(URL, File, int, int)} with reasonable timeouts to prevent this.
*
* @param source the URL to copy bytes from, must not be {@code null}
* @param destination the non-directory File to write bytes to (possibly
* overwriting), must not be {@code null}
* @throws IOException if source URL cannot be opened
* @throws IOException if destination is a directory
* @throws IOException if destination cannot be written
* @throws IOException if destination needs creating but can't be
* @throws IOException if an IO error occurs during copying
*/
public static void copyURLToFile(final URL source, final File destination) throws IOException {
Streams.copy(source.openStream(), destination);
}
/**
* Copies bytes from the URL source to a file destination. The
* directories up to destination will be created if they don't already exist.
* destination will be overwritten if it already exists.
*
* @param source the URL to copy bytes from, must not be {@code null}
* @param destination the non-directory File to write bytes to (possibly
* overwriting), must not be {@code null}
* @param connectionTimeout the number of milliseconds until this method will timeout if no
* connection could be established to the source
* @param readTimeout the number of milliseconds until this method will timeout if no data could
* be read from the source
* @throws IOException if source URL cannot be opened
* @throws IOException if destination is a directory
* @throws IOException if destination cannot be written
* @throws IOException if destination needs creating but can't be
* @throws IOException if an IO error occurs during copying
*/
public static void copyURLToFile(final URL source, final File destination, final int connectionTimeout,
final int readTimeout) throws IOException {
final URLConnection connection = source.openConnection();
connection.setConnectTimeout(connectionTimeout);
connection.setReadTimeout(readTimeout);
Streams.copy(connection.getInputStream(), destination);
}
// -----------------------------------------------------------------------
/**
* Deletes a directory recursively.
*
* @param directory directory to delete
* @throws IOException in case deletion is unsuccessful
*/
public static void deleteDir(final File directory) throws IOException {
if (!directory.exists()) {
return;
}
if (!isSymlink(directory)) {
cleanDir(directory);
}
if (!directory.delete()) {
final String message = "Unable to delete directory " + directory + ".";
throw new IOException(message);
}
}
/**
* Deletes a file, never throwing an exception. If file is a directory, delete it and all
* sub-directories.
*
* The difference between File.delete() and this method are:
*
* - A directory to be deleted does not have to be empty.
* - No exceptions are thrown when a file or directory cannot be deleted.
*
*
* @param file file or directory to delete, can be {@code null}
* @return {@code true} if the file or directory was deleted, otherwise {@code false}
*/
public static boolean safeDelete(final File file) {
if (file == null || !file.exists()) {
return false;
}
try {
if (file.isDirectory()) {
cleanDir(file);
}
}
catch (final Exception ignored) {
}
try {
return file.delete();
}
catch (final Exception ignored) {
return false;
}
}
/**
* Determines whether the {@code parent} directory contains the {@code child} element (a file or
* directory).
*
* Files are normalized before comparison.
*
* Edge cases:
*
* - A {@code directory} must not be null: if null, throw IllegalArgumentException
* - A {@code directory} must be a directory: if not a directory, throw
* IllegalArgumentException
* - A directory does not contain itself: return false
* - A null child file is not contained in any parent: return false
*
*
* @param directory the file to consider as the parent.
* @param child the file to consider as the child.
* @return true is the candidate leaf is under by the specified composite. False otherwise.
* @throws IOException if an IO error occurs while checking the files.
* @see FileNames#directoryContains(String, String)
*/
public static boolean directoryContains(final File directory, final File child) throws IOException {
// Fail fast against NullPointerException
if (directory == null) {
throw new IllegalArgumentException("Directory must not be null");
}
if (!directory.isDirectory()) {
throw new IllegalArgumentException("Not a directory: " + directory);
}
if (child == null) {
return false;
}
if (!directory.exists() || !child.exists()) {
return false;
}
// Canonicalize paths (normalizes relative paths)
final String canonicalParent = directory.getCanonicalPath();
final String canonicalChild = child.getCanonicalPath();
return FileNames.directoryContains(canonicalParent, canonicalChild);
}
/**
* Cleans a directory without deleting it.
*
* @param directory directory to clean
* @throws IOException in case cleaning is unsuccessful
*/
public static void cleanDir(final File directory) throws IOException {
if (!directory.exists()) {
final String message = directory + " does not exist";
throw new IllegalArgumentException(message);
}
if (!directory.isDirectory()) {
final String message = directory + " is not a directory";
throw new IllegalArgumentException(message);
}
final File[] files = directory.listFiles();
if (files == null) { // null if security restricted
throw new IOException("Failed to list contents of " + directory);
}
IOException exception = null;
for (final File file : files) {
try {
forceDelete(file);
}
catch (final IOException ioe) {
exception = ioe;
}
}
if (null != exception) {
throw exception;
}
}
// -----------------------------------------------------------------------
/**
* Waits for NFS to propagate a file creation, imposing a timeout.
*
* This method repeatedly tests {@link File#exists()} until it returns true up to the maximum
* time specified in seconds.
*
* @param file the file to check, must not be {@code null}
* @param seconds the maximum time in seconds to wait
* @return true if file exists
* @throws NullPointerException if the file is {@code null}
*/
public static boolean waitFor(final File file, final int seconds) {
int timeout = 0;
int tick = 0;
while (!file.exists()) {
if (tick++ >= 10) {
tick = 0;
if (timeout++ > seconds) {
return false;
}
}
try {
Thread.sleep(100);
}
catch (final InterruptedException ignore) {
// ignore exception
}
catch (final Exception ex) {
break;
}
}
return true;
}
// -----------------------------------------------------------------------
/**
* Reads the contents of a file line by line to a List of Strings. The file is always closed.
*
* @param file the file to read, must not be {@code null}
* @param encoding the encoding to use, {@code null} means platform default
* @return the list of Strings representing each line in the file, never {@code null}
* @throws IOException in case of an I/O error
*/
public static List readLines(final File file, final Charset encoding) throws IOException {
InputStream in = null;
try {
in = Streams.openInputStream(file);
return Streams.readLines(in, encoding);
}
finally {
Streams.safeClose(in);
}
}
/**
* Reads the contents of a file line by line to a List of Strings. The file is always closed.
*
* @param file the file to read, must not be {@code null}
* @param encoding the encoding to use, {@code null} means platform default
* @return the list of Strings representing each line in the file, never {@code null}
* @throws IOException in case of an I/O error
* @throws UnsupportedCharsetException thrown instead of {@link UnsupportedEncodingException}
*/
public static List readLines(final File file, final String encoding) throws IOException {
return readLines(file, Charsets.toCharset(encoding));
}
/**
* Reads the contents of a file line by line to a List of Strings using the default encoding for
* the VM. The file is always closed.
*
* @param file the file to read, must not be {@code null}
* @return the list of Strings representing each line in the file, never {@code null}
* @throws IOException in case of an I/O error
*/
public static List readLines(final File file) throws IOException {
BOMInputStream in = null;
try {
in = new BOMInputStream(Streams.openInputStream(file));
Charset cs = in.hasBOM() ? in.getBOMCharset() : Charset.defaultCharset();
return Streams.readLines(in, cs);
}
finally {
Streams.safeClose(in);
}
}
/**
* Returns an Iterator for the lines in a File.
*
* This method opens an InputStream for the file. When you have finished with the
* iterator you should close the stream to free internal resources. This can be done by calling
* the {@link LineIterator#close()} method.
*
* The recommended usage pattern is:
*
*
* LineIterator it = FileUtils.lineIterator(file, "UTF-8");
* try {
* while (it.hasNext()) {
* String line = it.nextLine();
* // / do something with line
* }
* }
* finally {
* LineIterator.safeClose(iterator);
* }
*
*
* If an exception occurs during the creation of the iterator, the underlying stream is closed.
*
* @param file the file to open for input, must not be {@code null}
* @param encoding the encoding to use, {@code null} means platform default
* @return an Iterator of the lines in the file, never {@code null}
* @throws IOException in case of an I/O error (file closed)
*/
public static LineIterator lineIterator(final File file, final String encoding) throws IOException {
InputStream in = null;
try {
in = Streams.openInputStream(file);
return Streams.lineIterator(in, encoding);
}
catch (IOException ex) {
Streams.safeClose(in);
throw ex;
}
catch (RuntimeException ex) {
Streams.safeClose(in);
throw ex;
}
}
/**
* Returns an Iterator for the lines in a File using the default encoding for the
* VM.
*
* @param file the file to open for input, must not be {@code null}
* @return an Iterator of the lines in the file, never {@code null}
* @throws IOException in case of an I/O error (file closed)
* @see #lineIterator(File, String)
*/
public static LineIterator lineIterator(final File file) throws IOException {
return lineIterator(file, null);
}
// -----------------------------------------------------------------------
/**
* Writes a CharSequence to a file creating the file if it does not exist using the default
* encoding for the VM.
*
* @param file the file to write
* @param data the content to write to the file
* @throws IOException in case of an I/O error
*/
public static void write(final File file, final CharSequence data) throws IOException {
write(file, data, Charset.defaultCharset(), false);
}
/**
* Writes a CharSequence to a file creating the file if it does not exist using the default
* encoding for the VM.
*
* @param file the file to write
* @param data the content to write to the file
* @param append if {@code true}, then the data will be added to the end of the file rather than
* overwriting
* @throws IOException in case of an I/O error
*/
public static void write(final File file, final CharSequence data, final boolean append) throws IOException {
write(file, data, Charset.defaultCharset(), append);
}
/**
* Writes a CharSequence to a file creating the file if it does not exist.
*
* @param file the file to write
* @param data the content to write to the file
* @param encoding the encoding to use, {@code null} means platform default
* @throws IOException in case of an I/O error
*/
public static void write(final File file, final CharSequence data, final Charset encoding) throws IOException {
write(file, data, encoding, false);
}
/**
* Writes a CharSequence to a file creating the file if it does not exist.
*
* @param file the file to write
* @param data the content to write to the file
* @param encoding the encoding to use, {@code null} means platform default
* @throws IOException in case of an I/O error
* @throws java.io.UnsupportedEncodingException if the encoding is not supported by the VM
*/
public static void write(final File file, final CharSequence data, final String encoding) throws IOException {
write(file, data, encoding, false);
}
/**
* Writes a CharSequence to a file creating the file if it does not exist.
*
* @param file the file to write
* @param data the content to write to the file
* @param encoding the encoding to use, {@code null} means platform default
* @param append if {@code true}, then the data will be added to the end of the file rather than
* overwriting
* @throws IOException in case of an I/O error
*/
public static void write(final File file, final CharSequence data, final Charset encoding, final boolean append)
throws IOException {
OutputStream out = null;
try {
out = Streams.openOutputStream(file, append);
Streams.write(data, out, encoding);
out.close(); // don't swallow close Exception if copy completes normally
}
finally {
Streams.safeClose(out);
}
}
/**
* Writes a CharSequence to a file creating the file if it does not exist.
*
* @param file the file to write
* @param data the content to write to the file
* @param encoding the encoding to use, {@code null} means platform default
* @param append if {@code true}, then the data will be added to the end of the file rather than
* overwriting
* @throws IOException in case of an I/O error
* @throws UnsupportedCharsetException thrown instead of {@link UnsupportedEncodingException}
*/
public static void write(final File file, final CharSequence data, final String encoding, final boolean append)
throws IOException {
write(file, data, Charsets.toCharset(encoding), append);
}
/**
* Writes a byte array to a file creating the file if it does not exist.
*
* NOTE: As from v1.3, the parent directories of the file will be created if they do not exist.
*
* @param file the file to write to
* @param data the content to write to the file
* @throws IOException in case of an I/O error
*/
public static void write(final File file, final byte[] data) throws IOException {
write(file, data, false);
}
/**
* Writes a byte array to a file creating the file if it does not exist.
*
* @param file the file to write to
* @param data the content to write to the file
* @param append if {@code true}, then bytes will be added to the end of the file rather than
* overwriting
* @throws IOException in case of an I/O error
*/
public static void write(final File file, final byte[] data, final boolean append)
throws IOException {
write(file, data, 0, data.length, append);
}
/**
* Writes {@code len} bytes from the specified byte array starting at offset {@code off} to a
* file, creating the file if it does not exist.
*
* @param file the file to write to
* @param data the content to write to the file
* @param off the start offset in the data
* @param len the number of bytes to write
* @throws IOException in case of an I/O error
*/
public static void write(final File file, final byte[] data, final int off, final int len)
throws IOException {
write(file, data, off, len, false);
}
/**
* Writes {@code len} bytes from the specified byte array starting at offset {@code off} to a
* file, creating the file if it does not exist.
*
* @param file the file to write to
* @param data the content to write to the file
* @param off the start offset in the data
* @param len the number of bytes to write
* @param append if {@code true}, then bytes will be added to the end of the file rather than
* overwriting
* @throws IOException in case of an I/O error
*/
public static void write(final File file, final byte[] data, final int off, final int len,
final boolean append) throws IOException {
OutputStream out = null;
try {
out = Streams.openOutputStream(file, append);
out.write(data, off, len);
out.close(); // don't swallow close Exception if copy completes normally
}
finally {
Streams.safeClose(out);
}
}
/**
* Writes stream to a file, creating the file if it does not exist.
*
* @param file the file to write to
* @param stream the content to write to the file
* @throws IOException in case of an I/O error
*/
public static void write(final File file, final InputStream stream) throws IOException {
write(file, stream, false);
}
/**
* Writes stream to a file, creating the file if it does not exist.
*
* @param file the file to write to
* @param stream the content to write to the file
* @param append if {@code true}, then bytes will be added to the end of the file rather than
* overwriting
* @throws IOException in case of an I/O error
*/
public static void write(final File file, final InputStream stream, final boolean append) throws IOException {
OutputStream out = null;
try {
out = Streams.openOutputStream(file, append);
Streams.copy(stream, out);
out.close(); // don't swallow close Exception if copy completes normally
}
finally {
Streams.safeClose(out);
}
}
/**
* Writes the toString() value of each item in a collection to the specified
* File line by line. The specified character encoding and the default line ending
* will be used.
*
* NOTE: As from v1.3, the parent directories of the file will be created if they do not exist.
*
* @param file the file to write to
* @param encoding the encoding to use, {@code null} means platform default
* @param lines the lines to write, {@code null} entries produce blank lines
* @throws IOException in case of an I/O error
* @throws java.io.UnsupportedEncodingException if the encoding is not supported by the VM
*/
public static void writeLines(final File file, final String encoding, final Collection lines) throws IOException {
writeLines(file, encoding, lines, null, false);
}
/**
* Writes the toString() value of each item in a collection to the specified
* File line by line, optionally appending. The specified character encoding and
* the default line ending will be used.
*
* @param file the file to write to
* @param encoding the encoding to use, {@code null} means platform default
* @param lines the lines to write, {@code null} entries produce blank lines
* @param append if {@code true}, then the lines will be added to the end of the file rather
* than overwriting
* @throws IOException in case of an I/O error
* @throws java.io.UnsupportedEncodingException if the encoding is not supported by the VM
*/
public static void writeLines(final File file, final String encoding, final Collection lines,
final boolean append) throws IOException {
writeLines(file, encoding, lines, null, append);
}
/**
* Writes the toString() value of each item in a collection to the specified
* File line by line. The default VM encoding and the default line ending will be
* used.
*
* @param file the file to write to
* @param lines the lines to write, {@code null} entries produce blank lines
* @throws IOException in case of an I/O error
*/
public static void writeLines(final File file, final Collection lines) throws IOException {
writeLines(file, null, lines, null, false);
}
/**
* Writes the toString() value of each item in a collection to the specified
* File line by line. The default VM encoding and the default line ending will be
* used.
*
* @param file the file to write to
* @param lines the lines to write, {@code null} entries produce blank lines
* @param append if {@code true}, then the lines will be added to the end of the file rather
* than overwriting
* @throws IOException in case of an I/O error
*/
public static void writeLines(final File file, final Collection lines, final boolean append) throws IOException {
writeLines(file, null, lines, null, append);
}
/**
* Writes the toString() value of each item in a collection to the specified
* File line by line. The specified character encoding and the line ending will be
* used.
*
* NOTE: As from v1.3, the parent directories of the file will be created if they do not exist.
*
* @param file the file to write to
* @param encoding the encoding to use, {@code null} means platform default
* @param lines the lines to write, {@code null} entries produce blank lines
* @param lineEnding the line separator to use, {@code null} is system default
* @throws IOException in case of an I/O error
* @throws java.io.UnsupportedEncodingException if the encoding is not supported by the VM
*/
public static void writeLines(final File file, final String encoding, final Collection lines,
final String lineEnding) throws IOException {
writeLines(file, encoding, lines, lineEnding, false);
}
/**
* Writes the toString() value of each item in a collection to the specified
* File line by line. The specified character encoding and the line ending will be
* used.
*
* @param file the file to write to
* @param encoding the encoding to use, {@code null} means platform default
* @param lines the lines to write, {@code null} entries produce blank lines
* @param lineEnding the line separator to use, {@code null} is system default
* @param append if {@code true}, then the lines will be added to the end of the file rather
* than overwriting
* @throws IOException in case of an I/O error
* @throws java.io.UnsupportedEncodingException if the encoding is not supported by the VM
*/
public static void writeLines(final File file, final String encoding, final Collection lines,
final String lineEnding, final boolean append) throws IOException {
FileOutputStream out = null;
try {
out = Streams.openOutputStream(file, append);
final BufferedOutputStream buffer = new BufferedOutputStream(out);
Streams.writeLines(lines, lineEnding, buffer, encoding);
buffer.flush();
out.close(); // don't swallow close Exception if copy completes normally
}
finally {
Streams.safeClose(out);
}
}
/**
* Writes the toString() value of each item in a collection to the specified
* File line by line. The default VM encoding and the specified line ending will be
* used.
*
* @param file the file to write to
* @param lines the lines to write, {@code null} entries produce blank lines
* @param lineEnding the line separator to use, {@code null} is system default
* @throws IOException in case of an I/O error
*/
public static void writeLines(final File file, final Collection lines, final String lineEnding)
throws IOException {
writeLines(file, null, lines, lineEnding, false);
}
/**
* Writes the toString() value of each item in a collection to the specified
* File line by line. The default VM encoding and the specified line ending will be
* used.
*
* @param file the file to write to
* @param lines the lines to write, {@code null} entries produce blank lines
* @param lineEnding the line separator to use, {@code null} is system default
* @param append if {@code true}, then the lines will be added to the end of the file rather
* than overwriting
* @throws IOException in case of an I/O error
*/
public static void writeLines(final File file, final Collection lines, final String lineEnding,
final boolean append) throws IOException {
writeLines(file, null, lines, lineEnding, append);
}
// -----------------------------------------------------------------------
/**
* Deletes a file. If file is a directory, delete it and all sub-directories.
*
* The difference between File.delete() and this method are:
*
* - A directory to be deleted does not have to be empty.
* - You get exceptions when a file or directory cannot be deleted. (java.io.File methods
* returns a boolean)
*
*
* @param file file or directory to delete, must not be {@code null}
* @throws NullPointerException if the directory is {@code null}
* @throws FileNotFoundException if the file was not found
* @throws IOException in case deletion is unsuccessful
*/
public static void forceDelete(final File file) throws IOException {
if (file.isDirectory()) {
deleteDir(file);
}
else {
final boolean filePresent = file.exists();
if (!file.delete()) {
if (!filePresent) {
throw new FileNotFoundException("File does not exist: " + file);
}
final String message = "Unable to delete file: " + file;
throw new IOException(message);
}
}
}
/**
* Schedules a file to be deleted when JVM exits. If file is directory delete it and all
* sub-directories.
*
* @param file file or directory to delete, must not be {@code null}
* @throws NullPointerException if the file is {@code null}
* @throws IOException in case deletion is unsuccessful
*/
public static void forceDeleteOnExit(final File file) throws IOException {
if (file.isDirectory()) {
deleteDirOnExit(file);
}
else {
file.deleteOnExit();
}
}
/**
* Schedules a directory recursively for deletion on JVM exit.
*
* @param directory directory to delete, must not be {@code null}
* @throws NullPointerException if the directory is {@code null}
* @throws IOException in case deletion is unsuccessful
*/
private static void deleteDirOnExit(final File directory) throws IOException {
if (!directory.exists()) {
return;
}
directory.deleteOnExit();
if (!isSymlink(directory)) {
cleanDirOnExit(directory);
}
}
/**
* Cleans a directory without deleting it.
*
* @param directory directory to clean, must not be {@code null}
* @throws NullPointerException if the directory is {@code null}
* @throws IOException in case cleaning is unsuccessful
*/
private static void cleanDirOnExit(final File directory) throws IOException {
if (!directory.exists()) {
final String message = directory + " does not exist";
throw new IllegalArgumentException(message);
}
if (!directory.isDirectory()) {
final String message = directory + " is not a directory";
throw new IllegalArgumentException(message);
}
final File[] files = directory.listFiles();
if (files == null) { // null if security restricted
throw new IOException("Failed to list contents of " + directory);
}
IOException exception = null;
for (final File file : files) {
try {
forceDeleteOnExit(file);
}
catch (final IOException ioe) {
exception = ioe;
}
}
if (null != exception) {
throw exception;
}
}
public static void makeDirs(final String directory) throws IOException {
makeDirs(new File(directory));
}
/**
* Makes a directory, including any necessary but nonexistent parent directories. If a file
* already exists with specified name but it is not a directory then an IOException is thrown.
* If the directory cannot be created (or does not already exist) then an IOException is thrown.
*
* @param directory directory to create, must not be {@code null}
* @throws NullPointerException if the directory is {@code null}
* @throws IOException if the directory cannot be created or the file already exists but is not
* a directory
*/
public static void makeDirs(final File directory) throws IOException {
if (directory.exists()) {
if (!directory.isDirectory()) {
final String message = "File " + directory + " exists and is "
+ "not a directory. Unable to create directory.";
throw new IOException(message);
}
}
else {
if (!directory.mkdirs()) {
// Double-check that some other thread or process hasn't made
// the directory in the background
if (!directory.isDirectory()) {
final String message = "Unable to create directory " + directory;
throw new IOException(message);
}
}
}
}
/**
* Makes any necessary but nonexistent parent directories for a given File. If the parent
* directory cannot be created then an IOException is thrown.
*
* @param file file with parent to create, must not be {@code null}
* @throws NullPointerException if the file is {@code null}
* @throws IOException if the parent directory cannot be created
*/
public static void makeParents(final File file) throws IOException {
final File parent = file.getParentFile();
if (parent == null) {
return;
}
makeDirs(parent);
}
// -----------------------------------------------------------------------
/**
* Returns the size of the specified file or directory. If the provided {@link File} is a
* regular file, then the file's length is returned. If the argument is a directory, then the
* size of the directory is calculated recursively. If a directory or subdirectory is security
* restricted, its size will not be included.
*
* @param file the regular file or directory to return the size of (must not be {@code null}).
* @return the length of the file, or recursive size of the directory, provided (in bytes).
* @throws NullPointerException if the file is {@code null}
* @throws IllegalArgumentException if the file does not exist.
*/
public static long sizeOf(final File file) {
if (!file.exists()) {
final String message = file + " does not exist";
throw new IllegalArgumentException(message);
}
if (file.isDirectory()) {
return sizeOfDir0(file); // private method; expects directory
}
else {
return file.length();
}
}
/**
* Returns the size of the specified file or directory. If the provided {@link File} is a
* regular file, then the file's length is returned. If the argument is a directory, then the
* size of the directory is calculated recursively. If a directory or subdirectory is security
* restricted, its size will not be included.
*
* @param file the regular file or directory to return the size of (must not be {@code null}).
* @return the length of the file, or recursive size of the directory, provided (in bytes).
* @throws NullPointerException if the file is {@code null}
* @throws IllegalArgumentException if the file does not exist.
*/
public static BigInteger sizeOfAsBigInteger(final File file) {
if (!file.exists()) {
final String message = file + " does not exist";
throw new IllegalArgumentException(message);
}
if (file.isDirectory()) {
return sizeOfDirBig0(file); // internal method
}
else {
return BigInteger.valueOf(file.length());
}
}
/**
* Counts the size of a directory recursively (sum of the length of all files).
*
* @param directory directory to inspect, must not be {@code null}
* @return size of directory in bytes, 0 if directory is security restricted, a negative number
* when the real total is greater than {@link Long#MAX_VALUE}.
* @throws NullPointerException if the directory is {@code null}
*/
public static long sizeOfDir(final File directory) {
checkDir(directory);
return sizeOfDir0(directory);
}
private static long sizeOfDir0(final File directory) {
final File[] files = directory.listFiles();
if (files == null) { // null if security restricted
return 0L;
}
long size = 0;
for (final File file : files) {
try {
if (!isSymlink(file)) {
size += sizeOf0(file); // internal method
if (size < 0) {
break;
}
}
}
catch (final IOException ioe) {
// Ignore exceptions caught when asking if a File is a symlink.
}
}
return size;
}
private static long sizeOf0(File file) {
if (file.isDirectory()) {
return sizeOfDir0(file);
}
else {
return file.length(); // will be 0 if file does not exist
}
}
/**
* Counts the size of a directory recursively (sum of the length of all files).
*
* @param directory directory to inspect, must not be {@code null}
* @return size of directory in bytes, 0 if directory is security restricted.
* @throws NullPointerException if the directory is {@code null}
*/
public static BigInteger sizeOfDirAsBigInteger(final File directory) {
checkDir(directory);
return sizeOfDirBig0(directory);
}
private static BigInteger sizeOfDirBig0(final File directory) {
final File[] files = directory.listFiles();
if (files == null) { // null if security restricted
return BigInteger.ZERO;
}
BigInteger size = BigInteger.ZERO;
for (final File file : files) {
try {
if (!isSymlink(file)) {
size = size.add(sizeOfBig0(file));
}
}
catch (final IOException ioe) {
// Ignore exceptions caught when asking if a File is a symlink.
}
}
return size;
}
private static BigInteger sizeOfBig0(final File fileOrDir) {
if (fileOrDir.isDirectory()) {
return sizeOfDirBig0(fileOrDir);
}
else {
return BigInteger.valueOf(fileOrDir.length());
}
}
/**
* Checks that the given {@code File} exists and is a directory.
*
* @param directory The {@code File} to check.
* @throws IllegalArgumentException if the given {@code File} does not exist or is not a
* directory.
*/
private static void checkDir(final File directory) {
if (!directory.exists()) {
throw new IllegalArgumentException(directory + " does not exist");
}
if (!directory.isDirectory()) {
throw new IllegalArgumentException(directory + " is not a directory");
}
}
// -----------------------------------------------------------------------
/**
* Tests if the specified File is newer than the reference File.
*
* @param file the File of which the modification date must be compared, must not
* be {@code null}
* @param reference the File of which the modification date is used, must not be
* {@code null}
* @return true if the File exists and has been modified more recently than the
* reference File
* @throws IllegalArgumentException if the file is {@code null}
* @throws IllegalArgumentException if the reference file is {@code null} or doesn't exist
*/
public static boolean isFileNewer(final File file, final File reference) {
if (reference == null) {
throw new IllegalArgumentException("No specified reference file");
}
if (!reference.exists()) {
throw new IllegalArgumentException("The reference file '" + reference + "' doesn't exist");
}
return isFileNewer(file, reference.lastModified());
}
/**
* Tests if the specified File is newer than the specified Date.
*
* @param file the File of which the modification date must be compared, must not
* be {@code null}
* @param date the date reference, must not be {@code null}
* @return true if the File exists and has been modified after the given
* Date.
* @throws IllegalArgumentException if the file is {@code null}
* @throws IllegalArgumentException if the date is {@code null}
*/
public static boolean isFileNewer(final File file, final Date date) {
if (date == null) {
throw new IllegalArgumentException("No specified date");
}
return isFileNewer(file, date.getTime());
}
/**
* Tests if the specified File is newer than the specified time reference.
*
* @param file the File of which the modification date must be compared, must not
* be {@code null}
* @param timeMillis the time reference measured in milliseconds since the epoch (00:00:00 GMT,
* January 1, 1970)
* @return true if the File exists and has been modified after the given time
* reference.
* @throws IllegalArgumentException if the file is {@code null}
*/
public static boolean isFileNewer(final File file, final long timeMillis) {
if (file == null) {
throw new IllegalArgumentException("No specified file");
}
if (!file.exists()) {
return false;
}
return file.lastModified() > timeMillis;
}
// -----------------------------------------------------------------------
/**
* Tests if the specified File is older than the reference File.
*
* @param file the File of which the modification date must be compared, must not
* be {@code null}
* @param reference the File of which the modification date is used, must not be
* {@code null}
* @return true if the File exists and has been modified before the reference
* File
* @throws IllegalArgumentException if the file is {@code null}
* @throws IllegalArgumentException if the reference file is {@code null} or doesn't exist
*/
public static boolean isFileOlder(final File file, final File reference) {
if (reference == null) {
throw new IllegalArgumentException("No specified reference file");
}
if (!reference.exists()) {
throw new IllegalArgumentException("The reference file '" + reference + "' doesn't exist");
}
return isFileOlder(file, reference.lastModified());
}
/**
* Tests if the specified File is older than the specified Date.
*
* @param file the File of which the modification date must be compared, must not
* be {@code null}
* @param date the date reference, must not be {@code null}
* @return true if the File exists and has been modified before the given
* Date.
* @throws IllegalArgumentException if the file is {@code null}
* @throws IllegalArgumentException if the date is {@code null}
*/
public static boolean isFileOlder(final File file, final Date date) {
if (date == null) {
throw new IllegalArgumentException("No specified date");
}
return isFileOlder(file, date.getTime());
}
/**
* Tests if the specified File is older than the specified time reference.
*
* @param file the File of which the modification date must be compared, must not
* be {@code null}
* @param timeMillis the time reference measured in milliseconds since the epoch (00:00:00 GMT,
* January 1, 1970)
* @return true if the File exists and has been modified before the given time
* reference.
* @throws IllegalArgumentException if the file is {@code null}
*/
public static boolean isFileOlder(final File file, final long timeMillis) {
if (file == null) {
throw new IllegalArgumentException("No specified file");
}
if (!file.exists()) {
return false;
}
return file.lastModified() < timeMillis;
}
// -----------------------------------------------------------------------
/**
* Computes the checksum of a file using the CRC32 checksum routine. The value of the checksum
* is returned.
*
* @param file the file to checksum, must not be {@code null}
* @return the checksum value
* @throws NullPointerException if the file or checksum is {@code null}
* @throws IllegalArgumentException if the file is a directory
* @throws IOException if an IO error occurs reading the file
*/
public static long checksumCRC32(final File file) throws IOException {
final CRC32 crc = new CRC32();
checksum(file, crc);
return crc.getValue();
}
/**
* Computes the checksum of a file using the specified checksum object. Multiple files may be
* checked using one Checksum instance if desired simply by reusing the same
* checksum object. For example:
*
*
* long csum = FileUtils.checksum(file, new CRC32()).getValue();
*
*
* @param file the file to checksum, must not be {@code null}
* @param checksum the checksum object to be used, must not be {@code null}
* @return the checksum specified, updated with the content of the file
* @throws NullPointerException if the file or checksum is {@code null}
* @throws IllegalArgumentException if the file is a directory
* @throws IOException if an IO error occurs reading the file
*/
public static Checksum checksum(final File file, final Checksum checksum) throws IOException {
if (file.isDirectory()) {
throw new IllegalArgumentException("Checksums can't be computed on directories");
}
InputStream in = null;
try {
in = new CheckedInputStream(new FileInputStream(file), checksum);
Streams.copy(in, Streams.nullOutputStream());
}
finally {
Streams.safeClose(in);
}
return checksum;
}
/**
* Moves a directory.
*
* When the destination directory is on another file system, do a "copy and delete".
*
* @param srcDir the directory to be moved
* @param destDir the destination directory
* @throws NullPointerException if source or destination is {@code null}
* @throws FileExistsException if the destination directory exists
* @throws IOException if source or destination is invalid
* @throws IOException if an IO error occurs moving the file
*/
public static void moveDir(final File srcDir, final File destDir) throws IOException {
if (srcDir == null) {
throw new NullPointerException("Source must not be null");
}
if (destDir == null) {
throw new NullPointerException("Destination must not be null");
}
if (!srcDir.exists()) {
throw new FileNotFoundException("Source '" + srcDir + "' does not exist");
}
if (!srcDir.isDirectory()) {
throw new IOException("Source '" + srcDir + "' is not a directory");
}
if (destDir.exists()) {
throw new FileExistsException("Destination '" + destDir + "' already exists");
}
final boolean rename = srcDir.renameTo(destDir);
if (!rename) {
if (destDir.getCanonicalPath().startsWith(srcDir.getCanonicalPath() + File.separator)) {
throw new IOException("Cannot move directory: " + srcDir + " to a subdirectory of itself: " + destDir);
}
copyDir(srcDir, destDir);
deleteDir(srcDir);
if (srcDir.exists()) {
throw new IOException("Failed to delete original directory '" + srcDir + "' after copy to '" + destDir
+ "'");
}
}
}
/**
* Moves a directory to another directory.
*
* @param src the file to be moved
* @param destDir the destination file
* @param createDestDir If {@code true} create the destination directory, otherwise if
* {@code false} throw an IOException
* @throws NullPointerException if source or destination is {@code null}
* @throws FileExistsException if the directory exists in the destination directory
* @throws IOException if source or destination is invalid
* @throws IOException if an IO error occurs moving the file
*/
public static void moveDirToDir(final File src, final File destDir, final boolean createDestDir)
throws IOException {
if (src == null) {
throw new NullPointerException("Source must not be null");
}
if (destDir == null) {
throw new NullPointerException("Destination directory must not be null");
}
if (!destDir.exists() && createDestDir) {
destDir.mkdirs();
}
if (!destDir.exists()) {
throw new FileNotFoundException("Destination directory '" + destDir + "' does not exist [createDestDir="
+ createDestDir + "]");
}
if (!destDir.isDirectory()) {
throw new IOException("Destination '" + destDir + "' is not a directory");
}
moveDir(src, new File(destDir, src.getName()));
}
/**
* Moves a file.
*
* When the destination file is on another file system, do a "copy and delete".
*
* @param srcFile the file to be moved
* @param destFile the destination file
* @throws NullPointerException if source or destination is {@code null}
* @throws FileExistsException if the destination file exists
* @throws IOException if source or destination is invalid
* @throws IOException if an IO error occurs moving the file
*/
public static void moveFile(final File srcFile, final File destFile) throws IOException {
if (srcFile == null) {
throw new NullPointerException("Source must not be null");
}
if (destFile == null) {
throw new NullPointerException("Destination must not be null");
}
if (!srcFile.exists()) {
throw new FileNotFoundException("Source '" + srcFile + "' does not exist");
}
if (srcFile.isDirectory()) {
throw new IOException("Source '" + srcFile + "' is a directory");
}
if (destFile.exists()) {
throw new FileExistsException("Destination '" + destFile + "' already exists");
}
if (destFile.isDirectory()) {
throw new IOException("Destination '" + destFile + "' is a directory");
}
final boolean rename = srcFile.renameTo(destFile);
if (!rename) {
copyFile(srcFile, destFile);
if (!srcFile.delete()) {
Files.safeDelete(destFile);
throw new IOException("Failed to delete original file '" + srcFile + "' after copy to '" + destFile
+ "'");
}
}
}
/**
* Moves a file to a directory.
*
* @param srcFile the file to be moved
* @param destDir the destination file
* @param createDestDir If {@code true} create the destination directory, otherwise if
* {@code false} throw an IOException
* @throws NullPointerException if source or destination is {@code null}
* @throws FileExistsException if the destination file exists
* @throws IOException if source or destination is invalid
* @throws IOException if an IO error occurs moving the file
*/
public static void moveFileToDiry(final File srcFile, final File destDir, final boolean createDestDir)
throws IOException {
if (srcFile == null) {
throw new NullPointerException("Source must not be null");
}
if (destDir == null) {
throw new NullPointerException("Destination directory must not be null");
}
if (!destDir.exists() && createDestDir) {
destDir.mkdirs();
}
if (!destDir.exists()) {
throw new FileNotFoundException("Destination directory '" + destDir + "' does not exist [createDestDir="
+ createDestDir + "]");
}
if (!destDir.isDirectory()) {
throw new IOException("Destination '" + destDir + "' is not a directory");
}
moveFile(srcFile, new File(destDir, srcFile.getName()));
}
/**
* Moves a file or directory to the destination directory.
*
* When the destination is on another file system, do a "copy and delete".
*
* @param src the file or directory to be moved
* @param destDir the destination directory
* @param createDestDir If {@code true} create the destination directory, otherwise if
* {@code false} throw an IOException
* @throws NullPointerException if source or destination is {@code null}
* @throws FileExistsException if the directory or file exists in the destination directory
* @throws IOException if source or destination is invalid
* @throws IOException if an IO error occurs moving the file
*/
public static void moveToDir(final File src, final File destDir, final boolean createDestDir)
throws IOException {
if (src == null) {
throw new NullPointerException("Source must not be null");
}
if (destDir == null) {
throw new NullPointerException("Destination must not be null");
}
if (!src.exists()) {
throw new FileNotFoundException("Source '" + src + "' does not exist");
}
if (src.isDirectory()) {
moveDirToDir(src, destDir, createDestDir);
}
else {
moveFileToDiry(src, destDir, createDestDir);
}
}
/**
* Determines whether the specified file is a Symbolic Link rather than an actual file.
*
* Will not return true if there is a Symbolic Link anywhere in the path, only if the specific
* file is.
*
* Note: the current implementation always returns {@code false} if the system is
* detected as Windows using {@link FileNames#isSystemWindows()}
*
* @param file the file to check
* @return true if the file is a Symbolic Link
* @throws IOException if an IO error occurs while checking the file
*/
public static boolean isSymlink(final String file) throws IOException {
return null != file && isSymlink(new File(file));
}
/**
* Determines whether the specified file is a Symbolic Link rather than an actual file.
*
* Will not return true if there is a Symbolic Link anywhere in the path, only if the specific
* file is.
*
* Note: the current implementation always returns {@code false} if the system is
* detected as Windows using {@link FileNames#isSystemWindows()}
*
* @param file the file to check
* @return true if the file is a Symbolic Link
* @throws IOException if an IO error occurs while checking the file
*/
public static boolean isSymlink(final File file) throws IOException {
if (file == null) {
throw new NullPointerException("File must not be null");
}
if (FileNames.isSystemWindows()) {
return false;
}
File fileInCanonicalDir = null;
if (file.getParent() == null) {
fileInCanonicalDir = file;
}
else {
final File canonicalDir = file.getParentFile().getCanonicalFile();
fileInCanonicalDir = new File(canonicalDir, file.getName());
}
if (fileInCanonicalDir.getCanonicalFile().equals(fileInCanonicalDir.getAbsoluteFile())) {
return false;
}
else {
return true;
}
}
}