com.android.utils

Class FileUtils

java.lang.Object

com.android.utils.FileUtils

public final class FileUtils
extends java.lang.Object

Method Summary

Modifier and Type	Method and Description
static void	cleanOutputDir(java.io.File path) Makes sure path is an empty directory.
static void	copyDirectory(java.io.File from, java.io.File to) Copies a directory from one path to another.
static void	copyDirectoryContentToDirectory(java.io.File from, java.io.File to) Makes a copy of the directory's content, in the specified location, while maintaining the directory structure.
static void	copyDirectoryToDirectory(java.io.File from, java.io.File to) Makes a copy of the given directory in the specified destination directory.
static void	copyFile(java.io.File from, java.io.File to) Copies a regular file from one path to another, preserving file attributes.
static void	copyFileToDirectory(java.io.File from, java.io.File to) Makes a copy of the given file in the specified directory, preserving the name and file attributes.
static void	createFile(java.io.File file, java.lang.String content) Creates a new text file with the given content.
static java.nio.file.FileSystem	createZipFilesystem(java.nio.file.Path archive) Creates a new FileSystem for a given ZIP file.
static void	delete(java.io.File file) Deletes an existing file or an existing empty directory.
static void	deleteDirectoryContents(java.io.File directory) Recursively deletes a directory content (including the sub directories) but not itself.
static void	deleteIfExists(java.io.File file) Deletes a file or an empty directory if it exists.
static void	deletePath(java.io.File path) Recursively deletes a path.
static void	deleteRecursivelyIfExists(java.io.File file) Deletes a file or a directory if it exists.
static java.util.List<java.io.File>	find(java.io.File base, java.util.regex.Pattern pattern) Find a list of files in a directory, using a specified path pattern.
static com.google.common.base.Optional<java.io.File>	find(java.io.File base, java.lang.String name) Find a file with the specified name in a given directory .
static com.google.common.collect.FluentIterable<java.io.File>	getAllFiles(java.io.File dir)
static java.lang.String	getDirectoryNameForJar(java.io.File inputFile) Chooses a directory name, based on a JAR file name, considering exploded-aar and classes.jar.
static java.lang.String	getNamesAsCommaSeparatedList(java.lang.Iterable<java.io.File> files)
static boolean	isFileInDirectory(java.io.File file, java.io.File directory) Returns true if a file/directory is in a given directory or in a subdirectory of the given directory, and false otherwise.
static boolean	isSameFile(java.io.File file1, java.io.File file2) Returns true if the two files refer to the same physical file, and false otherwise.
static java.io.File	join(java.io.File dir, java.lang.Iterable<java.lang.String> paths) Joins a list of path segments to a given File object.
static java.io.File	join(java.io.File dir, java.lang.String... paths) Joins a list of path segments to a given File object.
static java.lang.String	join(java.lang.Iterable<java.lang.String> paths) Joins a set of segment into a string, separating each segments with a host-specific path separator.
static java.lang.String	join(java.lang.String... paths) Joins a set of segment into a string, separating each segments with a host-specific path separator.
static java.lang.String	joinFilePaths(java.lang.Iterable<java.io.File> files) Join multiple file paths as String.
static java.lang.String	loadFileWithUnixLineSeparators(java.io.File file) Loads a text file forcing the line separator to be of Unix style '\n' rather than being Windows style '\r\n'.
static java.io.File	mkdirs(java.io.File folder) Creates a directory, if it doesn't exist.
static boolean	parentDirExists(java.io.File file) Returns true if the parent directory of the given file/directory exists, and false otherwise.
static java.lang.String	relativePath(java.io.File file, java.io.File dir) Computes the relative of a file or directory with respect to a directory.
static java.lang.String	relativePossiblyNonExistingPath(java.io.File file, java.io.File dir) Computes the relative of a file or directory with respect to a directory.
static void	renameTo(java.io.File file, java.io.File to)
static java.lang.String	sha1(java.io.File file)
static java.lang.String	toExportableSystemDependentPath(java.io.File file) Returns an absolute path that can be open by system APIs for all platforms.
static java.lang.String	toSystemDependentPath(java.lang.String path) Converts a /-based path into a path using the system dependent separator.
static java.lang.String	toSystemIndependentPath(java.lang.String path) Converts a system-dependent path into a /-based path.
static void	writeToFile(java.io.File file, java.lang.String content) Creates a new text file or replaces content of an existing file.

Methods inherited from class java.lang.Object

clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

Method Detail

deletePath

public static void deletePath(@NonNull
                              java.io.File path)
                       throws java.io.IOException

Recursively deletes a path.

Parameters:

path - the path delete, may exist or not

Throws:

java.io.IOException - failed to delete the file / directory

deleteDirectoryContents

public static void deleteDirectoryContents(@NonNull
                                           java.io.File directory)
                                    throws java.io.IOException

Recursively deletes a directory content (including the sub directories) but not itself.

Parameters:

directory - the directory, that must exist and be a valid directory

Throws:

java.io.IOException - failed to delete the file / directory

cleanOutputDir

public static void cleanOutputDir(@NonNull
                                  java.io.File path)
                           throws java.io.IOException

Makes sure path is an empty directory. If path is a directory, its contents are removed recursively, leaving an empty directory. If path is not a directory, it is removed and a directory created with the given path. If path does not exist, a directory is created with the given path.

Parameters:

path - the path, that may exist or not and may be a file or directory

Throws:

java.io.IOException - failed to delete directory contents, failed to delete path or failed to create a directory at path

copyFile

public static void copyFile(@NonNull
                            java.io.File from,
                            @NonNull
                            java.io.File to)
                     throws java.io.IOException

Copies a regular file from one path to another, preserving file attributes. If the destination file exists, it gets overwritten.

Throws:

java.io.IOException

copyDirectory

public static void copyDirectory(@NonNull
                                 java.io.File from,
                                 @NonNull
                                 java.io.File to)
                          throws java.io.IOException

Copies a directory from one path to another. If the destination directory exists, the file contents are merged and files from the source directory overwrite files in the destination.

Throws:

java.io.IOException

copyFileToDirectory

public static void copyFileToDirectory(@NonNull
                                       java.io.File from,
                                       @NonNull
                                       java.io.File to)
                                throws java.io.IOException

Makes a copy of the given file in the specified directory, preserving the name and file attributes.

Throws:

java.io.IOException

copyDirectoryToDirectory

public static void copyDirectoryToDirectory(@NonNull
                                            java.io.File from,
                                            @NonNull
                                            java.io.File to)
                                     throws java.io.IOException

Makes a copy of the given directory in the specified destination directory.

Throws:

java.io.IOException

See Also:

copyDirectory(File, File)

copyDirectoryContentToDirectory

public static void copyDirectoryContentToDirectory(@NonNull
                                                   java.io.File from,
                                                   @NonNull
                                                   java.io.File to)
                                            throws java.io.IOException

Makes a copy of the directory's content, in the specified location, while maintaining the directory structure. So the entire directory tree from the source will be copied.

Parameters:

from - directory from which the content is copied

to - destination directory, will be created if does not exist

Throws:

java.io.IOException

mkdirs

@NonNull
public static java.io.File mkdirs(@NonNull
                                           java.io.File folder)

Creates a directory, if it doesn't exist.

Parameters:

folder - the directory to create, may already exist

Returns:

folder

delete

public static void delete(@NonNull
                          java.io.File file)
                   throws java.io.IOException

Deletes an existing file or an existing empty directory.

Parameters:

file - the file or directory to delete. The file/directory must exist, if the directory exists, it must be empty.

Throws:

java.io.IOException

deleteIfExists

public static void deleteIfExists(@NonNull
                                  java.io.File file)
                           throws java.io.IOException

Deletes a file or an empty directory if it exists.

Parameters:

file - the file or directory to delete. The file/directory may not exist; if the directory exists, it must be empty.

Throws:

java.io.IOException

deleteRecursivelyIfExists

public static void deleteRecursivelyIfExists(@NonNull
                                             java.io.File file)
                                      throws java.io.IOException

Deletes a file or a directory if it exists. If the directory is not empty, its contents will be deleted recursively.

Parameters:

file - the file or directory to delete. The file/directory may not exist; if the directory exists, it may be non-empty.

Throws:

java.io.IOException

renameTo

public static void renameTo(@NonNull
                            java.io.File file,
                            @NonNull
                            java.io.File to)
                     throws java.io.IOException

Throws:

java.io.IOException

join

@NonNull
public static java.io.File join(@NonNull
                                         java.io.File dir,
                                         @NonNull
                                         java.lang.String... paths)

Joins a list of path segments to a given File object.

Parameters:

dir - the file object.

paths - the segments.

Returns:

a new File object.

join

@NonNull
public static java.io.File join(@NonNull
                                         java.io.File dir,
                                         @NonNull
                                         java.lang.Iterable<java.lang.String> paths)

Joins a list of path segments to a given File object.

Parameters:

dir - the file object.

paths - the segments.

Returns:

a new File object.

join

@NonNull
public static java.lang.String join(@NonNull
                                             java.lang.String... paths)

Joins a set of segment into a string, separating each segments with a host-specific path separator.

Parameters:

paths - the segments.

Returns:

a string with the segments.

join

@NonNull
public static java.lang.String join(@NonNull
                                             java.lang.Iterable<java.lang.String> paths)

Joins a set of segment into a string, separating each segments with a host-specific path separator.

Parameters:

paths - the segments.

Returns:

a string with the segments.

loadFileWithUnixLineSeparators

@NonNull
public static java.lang.String loadFileWithUnixLineSeparators(@NonNull
                                                                       java.io.File file)
                                                                throws java.io.IOException

Loads a text file forcing the line separator to be of Unix style '\n' rather than being Windows style '\r\n'.

Throws:

java.io.IOException

relativePath

@NonNull
public static java.lang.String relativePath(@NonNull
                                                     java.io.File file,
                                                     @NonNull
                                                     java.io.File dir)

Computes the relative of a file or directory with respect to a directory.

Parameters:

file - the file or directory, which must exist in the filesystem

dir - the directory to compute the path relative to

Returns:

the relative path from dir to file; if file is a directory the path comes appended with the file separator (see documentation on relativize on java's URI class)

relativePossiblyNonExistingPath

@NonNull
public static java.lang.String relativePossiblyNonExistingPath(@NonNull
                                                                        java.io.File file,
                                                                        @NonNull
                                                                        java.io.File dir)

Computes the relative of a file or directory with respect to a directory. For example, if the file's absolute path is /a/b/c and the directory is /a, this method returns b/c.

Parameters:

file - the path that may not correspond to any existing path in the filesystem

dir - the directory to compute the path relative to

Returns:

the relative path from dir to file; if file is a directory the path comes appended with the file separator (see documentation on relativize on java's URI class)

toSystemDependentPath

@NonNull
public static java.lang.String toSystemDependentPath(@NonNull
                                                              java.lang.String path)

Converts a /-based path into a path using the system dependent separator.

Parameters:

path - the system independent path to convert

Returns:

the system dependent path

toSystemIndependentPath

@NonNull
public static java.lang.String toSystemIndependentPath(@NonNull
                                                                java.lang.String path)

Converts a system-dependent path into a /-based path.

Parameters:

path - the system dependent path

Returns:

the system independent path

toExportableSystemDependentPath

@NonNull
public static java.lang.String toExportableSystemDependentPath(@NonNull
                                                                        java.io.File file)

Returns an absolute path that can be open by system APIs for all platforms.

Parameters:

file - The file whose path needs to be converted.

Returns:

On non-Windows platforms, the absolute path of the file. On Windows, the absolute path preceded by "\\?\". This ensures that Windows API calls can open the path even if it is more than 260 characters long.

sha1

@NonNull
public static java.lang.String sha1(@NonNull
                                             java.io.File file)
                                      throws java.io.IOException

Throws:

java.io.IOException

getAllFiles

@NonNull
public static com.google.common.collect.FluentIterable<java.io.File> getAllFiles(@NonNull
                                                                                          java.io.File dir)

getNamesAsCommaSeparatedList

@NonNull
public static java.lang.String getNamesAsCommaSeparatedList(@NonNull
                                                                     java.lang.Iterable<java.io.File> files)

getDirectoryNameForJar

@NonNull
public static java.lang.String getDirectoryNameForJar(@NonNull
                                                               java.io.File inputFile)

Chooses a directory name, based on a JAR file name, considering exploded-aar and classes.jar.

createFile

public static void createFile(@NonNull
                              java.io.File file,
                              @NonNull
                              java.lang.String content)
                       throws java.io.IOException

Creates a new text file with the given content. The file should not exist when this method is called.

Parameters:

file - the file to write to

content - the new content of the file

Throws:

java.io.IOException

writeToFile

public static void writeToFile(@NonNull
                               java.io.File file,
                               @NonNull
                               java.lang.String content)
                        throws java.io.IOException

Creates a new text file or replaces content of an existing file.

Parameters:

file - the file to write to

content - the new content of the file

Throws:

java.io.IOException

find

public static java.util.List<java.io.File> find(@NonNull
                                                java.io.File base,
                                                @NonNull
                                                java.util.regex.Pattern pattern)

Find a list of files in a directory, using a specified path pattern.

find

public static com.google.common.base.Optional<java.io.File> find(@NonNull
                                                                 java.io.File base,
                                                                 @NonNull
                                                                 java.lang.String name)

Find a file with the specified name in a given directory .

joinFilePaths

@NonNull
public static java.lang.String joinFilePaths(@NonNull
                                                      java.lang.Iterable<java.io.File> files)

Join multiple file paths as String.

parentDirExists

public static boolean parentDirExists(@NonNull
                                      java.io.File file)

Returns true if the parent directory of the given file/directory exists, and false otherwise. Note that this method resolves the real path of the given file/directory first via File.getCanonicalFile().

isFileInDirectory

public static boolean isFileInDirectory(@NonNull
                                        java.io.File file,
                                        @NonNull
                                        java.io.File directory)

Returns true if a file/directory is in a given directory or in a subdirectory of the given directory, and false otherwise. Note that this method resolves the real paths of the given file/directory first via File.getCanonicalFile().

isSameFile

public static boolean isSameFile(@NonNull
                                 java.io.File file1,
                                 @NonNull
                                 java.io.File file2)

Returns true if the two files refer to the same physical file, and false otherwise. This is the correct way to compare physical files, instead of comparing using File.equals(Object) directly.

Unlike Files.isSameFile(Path, Path), this method does not require the files to exist.

Internally, this method delegates to Files.isSameFile(Path, Path) if the files exist.

If either of the files does not exist, this method instead compares the canonical files of the two files, since Files.isSameFile(Path, Path) in some cases require that the files exist and therefore cannot be used. The downside of using File.getCanonicalFile() is that it may not handle hard links and symbolic links correctly as with Files.isSameFile(Path, Path).

createZipFilesystem

@NonNull
public static java.nio.file.FileSystem createZipFilesystem(@NonNull
                                                                    java.nio.file.Path archive)
                                                             throws java.io.IOException

Creates a new FileSystem for a given ZIP file.

Note that NIO filesystems are unique per URI, so the returned FileSystem should be closed as soon as possible.

Throws:

java.io.IOException