org.eclipse.jgit.util.FileUtils Maven / Gradle / Ivy
/*
* Copyright (C) 2010, Google Inc.
* Copyright (C) 2010, Matthias Sohn
* Copyright (C) 2010, Jens Baumgart
* and other copyright owners as documented in the project's IP log.
*
* This program and the accompanying materials are made available
* under the terms of the Eclipse Distribution License v1.0 which
* accompanies this distribution, is reproduced below, and is
* available at http://www.eclipse.org/org/documents/edl-v10.php
*
* All rights reserved.
*
* Redistribution and use in source and binary forms, with or
* without modification, are permitted provided that the following
* conditions are met:
*
* - Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
*
* - Redistributions in binary form must reproduce the above
* copyright notice, this list of conditions and the following
* disclaimer in the documentation and/or other materials provided
* with the distribution.
*
* - Neither the name of the Eclipse Foundation, Inc. nor the
* names of its contributors may be used to endorse or promote
* products derived from this software without specific prior
* written permission.
*
* THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND
* CONTRIBUTORS "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES,
* INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
* OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
* ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR
* CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
* SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
* NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
* LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER
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* ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF
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package org.eclipse.jgit.util;
import java.io.File;
import java.io.IOException;
import java.nio.channels.FileLock;
import java.text.MessageFormat;
import java.util.ArrayList;
import java.util.List;
import org.eclipse.jgit.internal.JGitText;
/**
* File Utilities
*/
public class FileUtils {
/**
* 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;
/**
* Delete file or empty folder
*
* @param f
* {@code File} to be deleted
* @throws 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 IOExceptions during race conditions when multiple
* concurrent threads all try to delete the same file.
*/
public static void delete(final 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 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 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(final 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 files = new ArrayList();
List 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 && !f.delete()) {
if ((options & RETRY) != 0 && fs.exists(f)) {
for (int i = 1; i < 10; i++) {
try {
Thread.sleep(100);
} catch (InterruptedException e) {
// ignore
}
if (f.delete())
return;
}
}
if ((options & IGNORE_ERRORS) == 0)
throw new IOException(MessageFormat.format(
JGitText.get().deleteFileFailed, f.getAbsolutePath()));
}
}
/**
* 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.
*
* This operation is not atomic.
*
* @see FS#retryFailedLockFileCommit()
* @param src
* the old {@code File}
* @param dst
* the new {@code File}
* @throws IOException
* if the rename has failed
* @since 3.0
*/
public static void rename(final File src, final File dst)
throws IOException {
int attempts = FS.DETECTED.retryFailedLockFileCommit() ? 10 : 1;
while (--attempts >= 0) {
if (src.renameTo(dst))
return;
try {
if (!dst.delete())
delete(dst, EMPTY_DIRECTORIES_ONLY | RECURSIVE);
// On *nix there is no try, you do or do not
if (src.renameTo(dst))
return;
} catch (IOException e) {
// ignore and continue retry
}
try {
Thread.sleep(100);
} catch (InterruptedException e) {
throw new IOException(MessageFormat.format(
JGitText.get().renameFileFailed, src.getAbsolutePath(),
dst.getAbsolutePath()));
}
}
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 IOException
* if creation of {@code d} fails. This may occur if {@code d}
* did exist when the method was called. This can therefore
* cause IOExceptions during race conditions when multiple
* concurrent threads all try to create the same directory.
*/
public static void mkdir(final 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 IOException
* if creation of {@code d} fails. This may occur if {@code d}
* did exist when the method was called. This can therefore
* cause IOExceptions during race conditions when multiple
* concurrent threads all try to create the same directory.
*/
public static void mkdir(final 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 IOException
* if creation of {@code d} fails. This may occur if {@code d}
* did exist when the method was called. This can therefore
* cause IOExceptions during race conditions when multiple
* concurrent threads all try to create the same directory.
*/
public static void mkdirs(final 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 IOException
* if creation of {@code d} fails. This may occur if {@code d}
* did exist when the method was called. This can therefore
* cause IOExceptions during race conditions when multiple
* concurrent threads all try to create the same directory.
*/
public static void mkdirs(final 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.
*
* Note: this method should not be used for file-locking, as the resulting
* protocol cannot be made to work reliably. The {@link FileLock} facility
* should be used instead.
*
* @param f
* the file to be created
* @throws 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
* @param target
* @throws IOException
* @since 3.0
*/
public static void createSymLink(File path, String target)
throws IOException {
FS.DETECTED.createSymLink(path, target);
}
/**
* @param path
* @return the target of the symbolic link, or null if it is not a symbolic
* link
* @throws IOException
* @since 3.0
*/
public static String readSymLink(File path) throws IOException {
return FS.DETECTED.readSymLink(path);
}
/**
* Create a temporary directory.
*
* @param prefix
* @param suffix
* @param dir
* The parent dir, can be null to use system default temp dir.
* @return the temp dir created.
* @throws IOException
* @since 3.4
*/
public static File createTempDir(String prefix, String suffix, File dir)
throws IOException {
final int RETRY = 1; // When something bad happens, retry once.
for (int i = 0; i < RETRY; i++) {
File tmp = File.createTempFile(prefix, suffix, dir);
if (!tmp.delete())
continue;
if (!tmp.mkdir())
continue;
return tmp;
}
throw new IOException(JGitText.get().cannotCreateTempDir);
}
}