Package org.apache.tomcat.util.http.fileupload

Class FileUtils

java.lang.Object

org.apache.tomcat.util.http.fileupload.FileUtils

public class FileUtils
extends Object

General file manipulation utilities.

Facilities are provided in the following areas:

• writing to a file
• reading from a file
• make a directory including parent directories
• copying files and directories
• deleting files and directories
• converting to and from a URL
• listing files and directories by filter and extension
• comparing file content
• file last changed date
• calculating a checksum

Note that a specific charset should be specified whenever possible. Relying on the platform default means that the code is Locale-dependent. Only use the default if the files are known to always use the platform default.

Origin of code: Excalibur, Alexandria, Commons-Utils

Constructor Summary

Constructors

Constructor	Description
FileUtils()	Instances should NOT be constructed in standard programming.

Method Summary

Modifier and Type	Method	Description
static void	cleanDirectory(File directory)	Cleans a directory without deleting it.
static void	deleteDirectory(File directory)	Deletes a directory recursively.
static void	forceDelete(File file)	Deletes a file.
static void	forceDeleteOnExit(File file)	Schedules a file to be deleted when JVM exits.
static void	forceMkdir(File directory)	Makes a directory, including any necessary but nonexistent parent directories.
static void	forceMkdirParent(File file)	Makes any necessary but nonexistent parent directories for a given File.
static boolean	isSymlink(File file)	Determines whether the specified file is a Symbolic Link rather than an actual file.

Methods inherited from class java.lang.Object

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

Constructor Details

FileUtils

public FileUtils()

Instances should NOT be constructed in standard programming.

Method Details

deleteDirectory

public static void deleteDirectory(File directory)
                            throws IOException

Deletes a directory recursively.

Parameters:

directory - directory to delete

Throws:

IOException - in case deletion is unsuccessful

IllegalArgumentException - if directory does not exist or is not a directory

cleanDirectory

public static void cleanDirectory(File directory)
                           throws IOException

Cleans a directory without deleting it.

Parameters:

directory - directory to clean

Throws:

IOException - in case cleaning is unsuccessful

IllegalArgumentException - if directory does not exist or is not a directory

forceDelete

public static void forceDelete(File file)
                        throws IOException

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)

Parameters:

file - file or directory to delete, must not be null

Throws:

NullPointerException - if the directory is null

FileNotFoundException - if the file was not found

IOException - in case deletion is unsuccessful

forceDeleteOnExit

public static void forceDeleteOnExit(File file)
                              throws IOException

Schedules a file to be deleted when JVM exits. If file is directory delete it and all sub-directories.

Parameters:

file - file or directory to delete, must not be null

Throws:

NullPointerException - if the file is null

IOException - in case deletion is unsuccessful

forceMkdir

public static void forceMkdir(File directory)
                       throws IOException

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.

Parameters:

directory - directory to create, must not be null

Throws:

NullPointerException - if the directory is null

IOException - if the directory cannot be created or the file already exists but is not a directory

forceMkdirParent

public static void forceMkdirParent(File file)
                             throws IOException

Makes any necessary but nonexistent parent directories for a given File. If the parent directory cannot be created then an IOException is thrown.

Parameters:

file - file with parent to create, must not be null

Throws:

NullPointerException - if the file is null

IOException - if the parent directory cannot be created

Since:

IO 2.5

isSymlink

public static boolean isSymlink(File file)
                         throws IOException

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 false if the system is detected as Windows using File.separatorChar == '\\'

Parameters:

file - the file to check

Returns:

true if the file is a Symbolic Link

Throws:

IOException - if an IO error occurs while checking the file

Since:

IO 2.0