FileUtils.java
/*
* Copyright (C) 2010, Google Inc.
* Copyright (C) 2010, Matthias Sohn <matthias.sohn@sap.com>
* Copyright (C) 2010, Jens Baumgart <jens.baumgart@sap.com> and others
*
* This program and the accompanying materials are made available under the
* terms of the Eclipse Distribution License v. 1.0 which is available at
* https://www.eclipse.org/org/documents/edl-v10.php.
*
* SPDX-License-Identifier: BSD-3-Clause
*/
package org.eclipse.jgit.util;
import static java.nio.charset.StandardCharsets.UTF_8;
import java.io.File;
import java.io.FileNotFoundException;
import java.io.IOException;
import java.nio.channels.FileChannel;
import java.nio.file.AtomicMoveNotSupportedException;
import java.nio.file.CopyOption;
import java.nio.file.DirectoryNotEmptyException;
import java.nio.file.Files;
import java.nio.file.InvalidPathException;
import java.nio.file.LinkOption;
import java.nio.file.NoSuchFileException;
import java.nio.file.Path;
import java.nio.file.StandardCopyOption;
import java.nio.file.StandardOpenOption;
import java.nio.file.attribute.BasicFileAttributeView;
import java.nio.file.attribute.BasicFileAttributes;
import java.nio.file.attribute.FileTime;
import java.nio.file.attribute.PosixFileAttributeView;
import java.nio.file.attribute.PosixFileAttributes;
import java.nio.file.attribute.PosixFilePermission;
import java.text.MessageFormat;
import java.text.Normalizer;
import java.text.Normalizer.Form;
import java.time.Instant;
import java.util.ArrayList;
import java.util.List;
import java.util.Locale;
import java.util.Random;
import java.util.regex.Pattern;
import java.util.stream.Stream;
import org.eclipse.jgit.internal.JGitText;
import org.eclipse.jgit.lib.Constants;
import org.eclipse.jgit.util.FS.Attributes;
import org.slf4j.Logger;
import org.slf4j.LoggerFactory;
/**
* File Utilities
*/
public class FileUtils {
private static final Logger LOG = LoggerFactory.getLogger(FileUtils.class);
private static final Random RNG = new Random();
/**
* Option to delete given {@code File}
*/
public static final int NONE = 0;
/**
* Option to recursively delete given {@code File}
*/
public static final int RECURSIVE = 1;
/**
* Option to retry deletion if not successful
*/
public static final int RETRY = 2;
/**
* Option to skip deletion if file doesn't exist
*/
public static final int SKIP_MISSING = 4;
/**
* Option not to throw exceptions when a deletion finally doesn't succeed.
* @since 2.0
*/
public static final int IGNORE_ERRORS = 8;
/**
* Option to only delete empty directories. This option can be combined with
* {@link #RECURSIVE}
*
* @since 3.0
*/
public static final int EMPTY_DIRECTORIES_ONLY = 16;
/**
* Safe conversion from {@link java.io.File} to {@link java.nio.file.Path}.
*
* @param f
* {@code File} to be converted to {@code Path}
* @return the path represented by the file
* @throws java.io.IOException
* in case the path represented by the file is not valid (
* {@link java.nio.file.InvalidPathException})
* @since 4.10
*/
public static Path toPath(File f) throws IOException {
try {
return f.toPath();
} catch (InvalidPathException ex) {
throw new IOException(ex);
}
}
/**
* Delete file or empty folder
*
* @param f
* {@code File} to be deleted
* @throws java.io.IOException
* if deletion of {@code f} fails. This may occur if {@code f}
* didn't exist when the method was called. This can therefore
* cause java.io.IOExceptions during race conditions when
* multiple concurrent threads all try to delete the same file.
*/
public static void delete(File f) throws IOException {
delete(f, NONE);
}
/**
* Delete file or folder
*
* @param f
* {@code File} to be deleted
* @param options
* deletion options, {@code RECURSIVE} for recursive deletion of
* a subtree, {@code RETRY} to retry when deletion failed.
* Retrying may help if the underlying file system doesn't allow
* deletion of files being read by another thread.
* @throws java.io.IOException
* if deletion of {@code f} fails. This may occur if {@code f}
* didn't exist when the method was called. This can therefore
* cause java.io.IOExceptions during race conditions when
* multiple concurrent threads all try to delete the same file.
* This exception is not thrown when IGNORE_ERRORS is set.
*/
public static void delete(File f, int options) throws IOException {
FS fs = FS.DETECTED;
if ((options & SKIP_MISSING) != 0 && !fs.exists(f))
return;
if ((options & RECURSIVE) != 0 && fs.isDirectory(f)) {
final File[] items = f.listFiles();
if (items != null) {
List<File> files = new ArrayList<>();
List<File> dirs = new ArrayList<>();
for (File c : items)
if (c.isFile())
files.add(c);
else
dirs.add(c);
// Try to delete files first, otherwise options
// EMPTY_DIRECTORIES_ONLY|RECURSIVE will delete empty
// directories before aborting, depending on order.
for (File file : files)
delete(file, options);
for (File d : dirs)
delete(d, options);
}
}
boolean delete = false;
if ((options & EMPTY_DIRECTORIES_ONLY) != 0) {
if (f.isDirectory()) {
delete = true;
} else if ((options & IGNORE_ERRORS) == 0) {
throw new IOException(MessageFormat.format(
JGitText.get().deleteFileFailed, f.getAbsolutePath()));
}
} else {
delete = true;
}
if (delete) {
IOException t = null;
Path p = f.toPath();
boolean tryAgain;
do {
tryAgain = false;
try {
Files.delete(p);
return;
} catch (NoSuchFileException | FileNotFoundException e) {
handleDeleteException(f, e, options,
SKIP_MISSING | IGNORE_ERRORS);
return;
} catch (DirectoryNotEmptyException e) {
handleDeleteException(f, e, options, IGNORE_ERRORS);
return;
} catch (IOException e) {
if (!f.canWrite()) {
tryAgain = f.setWritable(true);
}
if (!tryAgain) {
t = e;
}
}
} while (tryAgain);
if ((options & RETRY) != 0) {
for (int i = 1; i < 10; i++) {
try {
Thread.sleep(100);
} catch (InterruptedException ex) {
// ignore
}
try {
Files.deleteIfExists(p);
return;
} catch (IOException e) {
t = e;
}
}
}
handleDeleteException(f, t, options, IGNORE_ERRORS);
}
}
private static void handleDeleteException(File f, IOException e,
int allOptions, int checkOptions) throws IOException {
if (e != null && (allOptions & checkOptions) == 0) {
throw new IOException(MessageFormat.format(
JGitText.get().deleteFileFailed, f.getAbsolutePath()), e);
}
}
/**
* Rename a file or folder. If the rename fails and if we are running on a
* filesystem where it makes sense to repeat a failing rename then repeat
* the rename operation up to 9 times with 100ms sleep time between two
* calls. Furthermore if the destination exists and is directory hierarchy
* with only directories in it, the whole directory hierarchy will be
* deleted. If the target represents a non-empty directory structure, empty
* subdirectories within that structure may or may not be deleted even if
* the method fails. Furthermore if the destination exists and is a file
* then the file will be deleted and then the rename is retried.
* <p>
* This operation is <em>not</em> atomic.
*
* @see FS#retryFailedLockFileCommit()
* @param src
* the old {@code File}
* @param dst
* the new {@code File}
* @throws java.io.IOException
* if the rename has failed
* @since 3.0
*/
public static void rename(File src, File dst)
throws IOException {
rename(src, dst, StandardCopyOption.REPLACE_EXISTING);
}
/**
* Rename a file or folder using the passed
* {@link java.nio.file.CopyOption}s. If the rename fails and if we are
* running on a filesystem where it makes sense to repeat a failing rename
* then repeat the rename operation up to 9 times with 100ms sleep time
* between two calls. Furthermore if the destination exists and is a
* directory hierarchy with only directories in it, the whole directory
* hierarchy will be deleted. If the target represents a non-empty directory
* structure, empty subdirectories within that structure may or may not be
* deleted even if the method fails. Furthermore if the destination exists
* and is a file then the file will be replaced if
* {@link java.nio.file.StandardCopyOption#REPLACE_EXISTING} has been set.
* If {@link java.nio.file.StandardCopyOption#ATOMIC_MOVE} has been set the
* rename will be done atomically or fail with an
* {@link java.nio.file.AtomicMoveNotSupportedException}
*
* @param src
* the old file
* @param dst
* the new file
* @param options
* options to pass to
* {@link java.nio.file.Files#move(java.nio.file.Path, java.nio.file.Path, CopyOption...)}
* @throws java.nio.file.AtomicMoveNotSupportedException
* if file cannot be moved as an atomic file system operation
* @throws java.io.IOException
* @since 4.1
*/
public static void rename(final File src, final File dst,
CopyOption... options)
throws AtomicMoveNotSupportedException, IOException {
int attempts = FS.DETECTED.retryFailedLockFileCommit() ? 10 : 1;
while (--attempts >= 0) {
try {
Files.move(toPath(src), toPath(dst), options);
return;
} catch (AtomicMoveNotSupportedException e) {
throw e;
} catch (IOException e) {
try {
if (!dst.delete()) {
delete(dst, EMPTY_DIRECTORIES_ONLY | RECURSIVE);
}
// On *nix there is no try, you do or do not
Files.move(toPath(src), toPath(dst), options);
return;
} catch (IOException e2) {
// ignore and continue retry
}
}
try {
Thread.sleep(100);
} catch (InterruptedException e) {
throw new IOException(
MessageFormat.format(JGitText.get().renameFileFailed,
src.getAbsolutePath(), dst.getAbsolutePath()),
e);
}
}
throw new IOException(
MessageFormat.format(JGitText.get().renameFileFailed,
src.getAbsolutePath(), dst.getAbsolutePath()));
}
/**
* Creates the directory named by this abstract pathname.
*
* @param d
* directory to be created
* @throws java.io.IOException
* if creation of {@code d} fails. This may occur if {@code d}
* did exist when the method was called. This can therefore
* cause java.io.IOExceptions during race conditions when
* multiple concurrent threads all try to create the same
* directory.
*/
public static void mkdir(File d)
throws IOException {
mkdir(d, false);
}
/**
* Creates the directory named by this abstract pathname.
*
* @param d
* directory to be created
* @param skipExisting
* if {@code true} skip creation of the given directory if it
* already exists in the file system
* @throws java.io.IOException
* if creation of {@code d} fails. This may occur if {@code d}
* did exist when the method was called. This can therefore
* cause java.io.IOExceptions during race conditions when
* multiple concurrent threads all try to create the same
* directory.
*/
public static void mkdir(File d, boolean skipExisting)
throws IOException {
if (!d.mkdir()) {
if (skipExisting && d.isDirectory())
return;
throw new IOException(MessageFormat.format(
JGitText.get().mkDirFailed, d.getAbsolutePath()));
}
}
/**
* Creates the directory named by this abstract pathname, including any
* necessary but nonexistent parent directories. Note that if this operation
* fails it may have succeeded in creating some of the necessary parent
* directories.
*
* @param d
* directory to be created
* @throws java.io.IOException
* if creation of {@code d} fails. This may occur if {@code d}
* did exist when the method was called. This can therefore
* cause java.io.IOExceptions during race conditions when
* multiple concurrent threads all try to create the same
* directory.
*/
public static void mkdirs(File d) throws IOException {
mkdirs(d, false);
}
/**
* Creates the directory named by this abstract pathname, including any
* necessary but nonexistent parent directories. Note that if this operation
* fails it may have succeeded in creating some of the necessary parent
* directories.
*
* @param d
* directory to be created
* @param skipExisting
* if {@code true} skip creation of the given directory if it
* already exists in the file system
* @throws java.io.IOException
* if creation of {@code d} fails. This may occur if {@code d}
* did exist when the method was called. This can therefore
* cause java.io.IOExceptions during race conditions when
* multiple concurrent threads all try to create the same
* directory.
*/
public static void mkdirs(File d, boolean skipExisting)
throws IOException {
if (!d.mkdirs()) {
if (skipExisting && d.isDirectory())
return;
throw new IOException(MessageFormat.format(
JGitText.get().mkDirsFailed, d.getAbsolutePath()));
}
}
/**
* Atomically creates a new, empty file named by this abstract pathname if
* and only if a file with this name does not yet exist. The check for the
* existence of the file and the creation of the file if it does not exist
* are a single operation that is atomic with respect to all other
* filesystem activities that might affect the file.
* <p>
* Note: this method should not be used for file-locking, as the resulting
* protocol cannot be made to work reliably. The
* {@link java.nio.channels.FileLock} facility should be used instead.
*
* @param f
* the file to be created
* @throws java.io.IOException
* if the named file already exists or if an I/O error occurred
*/
public static void createNewFile(File f) throws IOException {
if (!f.createNewFile())
throw new IOException(MessageFormat.format(
JGitText.get().createNewFileFailed, f));
}
/**
* Create a symbolic link
*
* @param path
* the path of the symbolic link to create
* @param target
* the target of the symbolic link
* @return the path to the symbolic link
* @throws java.io.IOException
* @since 4.2
*/
public static Path createSymLink(File path, String target)
throws IOException {
Path nioPath = toPath(path);
if (Files.exists(nioPath, LinkOption.NOFOLLOW_LINKS)) {
BasicFileAttributes attrs = Files.readAttributes(nioPath,
BasicFileAttributes.class, LinkOption.NOFOLLOW_LINKS);
if (attrs.isRegularFile() || attrs.isSymbolicLink()) {
delete(path);
} else {
delete(path, EMPTY_DIRECTORIES_ONLY | RECURSIVE);
}
}
if (SystemReader.getInstance().isWindows()) {
target = target.replace('/', '\\');
}
Path nioTarget = toPath(new File(target));
return Files.createSymbolicLink(nioPath, nioTarget);
}
/**
* Read target path of the symlink.
*
* @param path
* a {@link java.io.File} object.
* @return target path of the symlink, or null if it is not a symbolic link
* @throws java.io.IOException
* @since 3.0
*/
public static String readSymLink(File path) throws IOException {
Path nioPath = toPath(path);
Path target = Files.readSymbolicLink(nioPath);
String targetString = target.toString();
if (SystemReader.getInstance().isWindows()) {
targetString = targetString.replace('\\', '/');
} else if (SystemReader.getInstance().isMacOS()) {
targetString = Normalizer.normalize(targetString, Form.NFC);
}
return targetString;
}
/**
* Create a temporary directory.
*
* @param prefix
* prefix string
* @param suffix
* suffix string
* @param dir
* The parent dir, can be null to use system default temp dir.
* @return the temp dir created.
* @throws java.io.IOException
* @since 3.4
*/
public static File createTempDir(String prefix, String suffix, File dir)
throws IOException {
final int RETRIES = 1; // When something bad happens, retry once.
for (int i = 0; i < RETRIES; i++) {
File tmp = File.createTempFile(prefix, suffix, dir);
if (!tmp.delete())
continue;
if (!tmp.mkdir())
continue;
return tmp;
}
throw new IOException(JGitText.get().cannotCreateTempDir);
}
/**
* Expresses <code>other</code> as a relative file path from
* <code>base</code>. File-separator and case sensitivity are based on the
* current file system.
*
* See also
* {@link org.eclipse.jgit.util.FileUtils#relativizePath(String, String, String, boolean)}.
*
* @param base
* Base path
* @param other
* Destination path
* @return Relative path from <code>base</code> to <code>other</code>
* @since 4.8
*/
public static String relativizeNativePath(String base, String other) {
return FS.DETECTED.relativize(base, other);
}
/**
* Expresses <code>other</code> as a relative file path from
* <code>base</code>. File-separator and case sensitivity are based on Git's
* internal representation of files (which matches Unix).
*
* See also
* {@link org.eclipse.jgit.util.FileUtils#relativizePath(String, String, String, boolean)}.
*
* @param base
* Base path
* @param other
* Destination path
* @return Relative path from <code>base</code> to <code>other</code>
* @since 4.8
*/
public static String relativizeGitPath(String base, String other) {
return relativizePath(base, other, "/", false); //$NON-NLS-1$
}
/**
* Expresses <code>other</code> as a relative file path from <code>base</code>
* <p>
* For example, if called with the two following paths :
*
* <pre>
* <code>base = "c:\\Users\\jdoe\\eclipse\\git\\project"</code>
* <code>other = "c:\\Users\\jdoe\\eclipse\\git\\another_project\\pom.xml"</code>
* </pre>
*
* This will return "..\\another_project\\pom.xml".
*
* <p>
* <b>Note</b> that this will return the empty String if <code>base</code>
* and <code>other</code> are equal.
* </p>
*
* @param base
* The path against which <code>other</code> should be
* relativized. This will be assumed to denote the path to a
* folder and not a file.
* @param other
* The path that will be made relative to <code>base</code>.
* @param dirSeparator
* A string that separates components of the path. In practice, this is "/" or "\\".
* @param caseSensitive
* Whether to consider differently-cased directory names as distinct
* @return A relative path that, when resolved against <code>base</code>,
* will yield the original <code>other</code>.
* @since 4.8
*/
public static String relativizePath(String base, String other, String dirSeparator, boolean caseSensitive) {
if (base.equals(other))
return ""; //$NON-NLS-1$
final String[] baseSegments = base.split(Pattern.quote(dirSeparator));
final String[] otherSegments = other.split(Pattern
.quote(dirSeparator));
int commonPrefix = 0;
while (commonPrefix < baseSegments.length
&& commonPrefix < otherSegments.length) {
if (caseSensitive
&& baseSegments[commonPrefix]
.equals(otherSegments[commonPrefix]))
commonPrefix++;
else if (!caseSensitive
&& baseSegments[commonPrefix]
.equalsIgnoreCase(otherSegments[commonPrefix]))
commonPrefix++;
else
break;
}
final StringBuilder builder = new StringBuilder();
for (int i = commonPrefix; i < baseSegments.length; i++)
builder.append("..").append(dirSeparator); //$NON-NLS-1$
for (int i = commonPrefix; i < otherSegments.length; i++) {
builder.append(otherSegments[i]);
if (i < otherSegments.length - 1)
builder.append(dirSeparator);
}
return builder.toString();
}
/**
* Determine if an IOException is a Stale NFS File Handle
*
* @param ioe
* an {@link java.io.IOException} object.
* @return a boolean true if the IOException is a Stale NFS FIle Handle
* @since 4.1
*/
public static boolean isStaleFileHandle(IOException ioe) {
String msg = ioe.getMessage();
return msg != null
&& msg.toLowerCase(Locale.ROOT)
.matches("stale .*file .*handle"); //$NON-NLS-1$
}
/**
* Determine if a throwable or a cause in its causal chain is a Stale NFS
* File Handle
*
* @param throwable
* a {@link java.lang.Throwable} object.
* @return a boolean true if the throwable or a cause in its causal chain is
* a Stale NFS File Handle
* @since 4.7
*/
public static boolean isStaleFileHandleInCausalChain(Throwable throwable) {
while (throwable != null) {
if (throwable instanceof IOException
&& isStaleFileHandle((IOException) throwable)) {
return true;
}
throwable = throwable.getCause();
}
return false;
}
/**
* @param file
* @return {@code true} if the passed file is a symbolic link
*/
static boolean isSymlink(File file) {
return Files.isSymbolicLink(file.toPath());
}
/**
* @param file
* @return lastModified attribute for given file, not following symbolic
* links
* @throws IOException
* @deprecated use {@link #lastModifiedInstant(Path)} instead which returns
* FileTime
*/
@Deprecated
static long lastModified(File file) throws IOException {
return Files.getLastModifiedTime(toPath(file), LinkOption.NOFOLLOW_LINKS)
.toMillis();
}
/**
* @param path
* @return lastModified attribute for given file, not following symbolic
* links
*/
static Instant lastModifiedInstant(Path path) {
try {
return Files.getLastModifiedTime(path, LinkOption.NOFOLLOW_LINKS)
.toInstant();
} catch (NoSuchFileException e) {
LOG.debug(
"Cannot read lastModifiedInstant since path {} does not exist", //$NON-NLS-1$
path);
return Instant.EPOCH;
} catch (IOException e) {
LOG.error(MessageFormat
.format(JGitText.get().readLastModifiedFailed, path), e);
return Instant.ofEpochMilli(path.toFile().lastModified());
}
}
/**
* Return all the attributes of a file, without following symbolic links.
*
* @param file
* @return {@link BasicFileAttributes} of the file
* @throws IOException in case of any I/O errors accessing the file
*
* @since 4.5.6
*/
static BasicFileAttributes fileAttributes(File file) throws IOException {
return Files.readAttributes(file.toPath(), BasicFileAttributes.class, LinkOption.NOFOLLOW_LINKS);
}
/**
* Set the last modified time of a file system object.
*
* @param file
* @param time
* @throws IOException
*/
@Deprecated
static void setLastModified(File file, long time) throws IOException {
Files.setLastModifiedTime(toPath(file), FileTime.fromMillis(time));
}
/**
* Set the last modified time of a file system object.
*
* @param path
* @param time
* @throws IOException
*/
static void setLastModified(Path path, Instant time)
throws IOException {
Files.setLastModifiedTime(path, FileTime.from(time));
}
/**
* @param file
* @return {@code true} if the given file exists, not following symbolic
* links
*/
static boolean exists(File file) {
return Files.exists(file.toPath(), LinkOption.NOFOLLOW_LINKS);
}
/**
* @param file
* @return {@code true} if the given file is hidden
* @throws IOException
*/
static boolean isHidden(File file) throws IOException {
return Files.isHidden(toPath(file));
}
/**
* Set a file hidden (on Windows)
*
* @param file
* a {@link java.io.File} object.
* @param hidden
* a boolean.
* @throws java.io.IOException
* @since 4.1
*/
public static void setHidden(File file, boolean hidden) throws IOException {
Files.setAttribute(toPath(file), "dos:hidden", Boolean.valueOf(hidden), //$NON-NLS-1$
LinkOption.NOFOLLOW_LINKS);
}
/**
* Get file length
*
* @param file
* a {@link java.io.File}.
* @return length of the given file
* @throws java.io.IOException
* @since 4.1
*/
public static long getLength(File file) throws IOException {
Path nioPath = toPath(file);
if (Files.isSymbolicLink(nioPath))
return Files.readSymbolicLink(nioPath).toString()
.getBytes(UTF_8).length;
return Files.size(nioPath);
}
/**
* @param file
* @return {@code true} if the given file is a directory, not following
* symbolic links
*/
static boolean isDirectory(File file) {
return Files.isDirectory(file.toPath(), LinkOption.NOFOLLOW_LINKS);
}
/**
* @param file
* @return {@code true} if the given file is a file, not following symbolic
* links
*/
static boolean isFile(File file) {
return Files.isRegularFile(file.toPath(), LinkOption.NOFOLLOW_LINKS);
}
/**
* Whether the path is a directory with files in it.
*
* @param dir
* directory path
* @return {@code true} if the given directory path contains files
* @throws IOException
* on any I/O errors accessing the path
*
* @since 5.11
*/
public static boolean hasFiles(Path dir) throws IOException {
try (Stream<Path> stream = Files.list(dir)) {
return stream.findAny().isPresent();
}
}
/**
* Whether the given file can be executed.
*
* @param file
* a {@link java.io.File} object.
* @return {@code true} if the given file can be executed.
* @since 4.1
*/
public static boolean canExecute(File file) {
if (!isFile(file)) {
return false;
}
return Files.isExecutable(file.toPath());
}
/**
* @param fs
* @param file
* @return non null attributes object
*/
static Attributes getFileAttributesBasic(FS fs, File file) {
try {
Path nioPath = toPath(file);
BasicFileAttributes readAttributes = nioPath
.getFileSystem()
.provider()
.getFileAttributeView(nioPath,
BasicFileAttributeView.class,
LinkOption.NOFOLLOW_LINKS).readAttributes();
Attributes attributes = new Attributes(fs, file,
true,
readAttributes.isDirectory(),
fs.supportsExecute() ? file.canExecute() : false,
readAttributes.isSymbolicLink(),
readAttributes.isRegularFile(), //
readAttributes.creationTime().toMillis(), //
readAttributes.lastModifiedTime().toInstant(),
readAttributes.isSymbolicLink() ? Constants
.encode(readSymLink(file)).length
: readAttributes.size());
return attributes;
} catch (IOException e) {
return new Attributes(file, fs);
}
}
/**
* Get file system attributes for the given file.
*
* @param fs
* a {@link org.eclipse.jgit.util.FS} object.
* @param file
* a {@link java.io.File}.
* @return file system attributes for the given file.
* @since 4.1
*/
public static Attributes getFileAttributesPosix(FS fs, File file) {
try {
Path nioPath = toPath(file);
PosixFileAttributes readAttributes = nioPath
.getFileSystem()
.provider()
.getFileAttributeView(nioPath,
PosixFileAttributeView.class,
LinkOption.NOFOLLOW_LINKS).readAttributes();
Attributes attributes = new Attributes(
fs,
file,
true, //
readAttributes.isDirectory(), //
readAttributes.permissions().contains(
PosixFilePermission.OWNER_EXECUTE),
readAttributes.isSymbolicLink(),
readAttributes.isRegularFile(), //
readAttributes.creationTime().toMillis(), //
readAttributes.lastModifiedTime().toInstant(),
readAttributes.size());
return attributes;
} catch (IOException e) {
return new Attributes(file, fs);
}
}
/**
* NFC normalize a file (on Mac), otherwise do nothing
*
* @param file
* a {@link java.io.File}.
* @return on Mac: NFC normalized {@link java.io.File}, otherwise the passed
* file
* @since 4.1
*/
public static File normalize(File file) {
if (SystemReader.getInstance().isMacOS()) {
// TODO: Would it be faster to check with isNormalized first
// assuming normalized paths are much more common
String normalized = Normalizer.normalize(file.getPath(),
Normalizer.Form.NFC);
return new File(normalized);
}
return file;
}
/**
* On Mac: get NFC normalized form of given name, otherwise the given name.
*
* @param name
* a {@link java.lang.String} object.
* @return on Mac: NFC normalized form of given name
* @since 4.1
*/
public static String normalize(String name) {
if (SystemReader.getInstance().isMacOS()) {
if (name == null)
return null;
return Normalizer.normalize(name, Normalizer.Form.NFC);
}
return name;
}
/**
* Best-effort variation of {@link java.io.File#getCanonicalFile()}
* returning the input file if the file cannot be canonicalized instead of
* throwing {@link java.io.IOException}.
*
* @param file
* to be canonicalized; may be {@code null}
* @return canonicalized file, or the unchanged input file if
* canonicalization failed or if {@code file == null}
* @throws java.lang.SecurityException
* if {@link java.io.File#getCanonicalFile()} throws one
* @since 4.2
*/
public static File canonicalize(File file) {
if (file == null) {
return null;
}
try {
return file.getCanonicalFile();
} catch (IOException e) {
return file;
}
}
/**
* Convert a path to String, replacing separators as necessary.
*
* @param file
* a {@link java.io.File}.
* @return file's path as a String
* @since 4.10
*/
public static String pathToString(File file) {
final String path = file.getPath();
if (SystemReader.getInstance().isWindows()) {
return path.replace('\\', '/');
}
return path;
}
/**
* Touch the given file
*
* @param f
* the file to touch
* @throws IOException
* @since 5.1.8
*/
public static void touch(Path f) throws IOException {
try (FileChannel fc = FileChannel.open(f, StandardOpenOption.CREATE,
StandardOpenOption.APPEND, StandardOpenOption.SYNC)) {
// touch
}
Files.setLastModifiedTime(f, FileTime.from(Instant.now()));
}
/**
* Compute a delay in a {@code min..max} interval with random jitter.
*
* @param last
* amount of delay waited before the last attempt. This is used
* to seed the next delay interval. Should be 0 if there was no
* prior delay.
* @param min
* shortest amount of allowable delay between attempts.
* @param max
* longest amount of allowable delay between attempts.
* @return new amount of delay to wait before the next attempt.
*
* @since 5.6
*/
public static long delay(long last, long min, long max) {
long r = Math.max(0, last * 3 - min);
if (r > 0) {
int c = (int) Math.min(r + 1, Integer.MAX_VALUE);
r = RNG.nextInt(c);
}
return Math.max(Math.min(min + r, max), min);
}
}