com.aspectran.core.util

Class FilenameUtils

java.lang.Object

com.aspectran.core.util.FilenameUtils

public class FilenameUtils
extends Object

Utility methods for General filename and filepath manipulation.

This class defines six components within a filename (example C:\dev\project\file.txt):

• the prefix - C:\
• the path - dev\project\
• the full path - C:\dev\project\
• the name - file.txt
• the base name - file
• the extension - txt

Constructor Summary

Constructors

Constructor and Description
FilenameUtils()

Method Summary

Modifier and Type	Method and Description
static File	generateSafetyUniqueFile(File file) Creates and returns a safe file name on the system without duplication in the specified directory.
static String	getBaseName(String filename) Gets the base name, minus the full path and extension, from a full filename.
static String	getExtension(String filename) Gets the extension of a filename.
static String	getFullPath(String filename) Gets the path from a full filename.
static String	getFullPathWithEndSeprator(String filename) Gets the path with end separator from a full filename.
static String	getName(String filename) Gets the name minus the path from a full filename.
static int	indexOfExtension(String filename) Returns the index of the last extension separator character, which is a dot.
static int	indexOfLastSeparator(String filename) Returns the index of the last directory separator character.
static boolean	isValidFileExtension(String filename, String allowedFileExtensions, String deniedFileExtensions) Checks whether the extension of the filename is valid.
static String	removeExtension(String filename) Removes the extension from a filename.
static File	seekUniqueFile(File srcFile) Returns a file name that does not overlap in the specified directory.
static File	seekUniqueFile(File srcFile, char extSeparator) Returns a file name that does not overlap in the specified directory.

Methods inherited from class java.lang.Object

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

Constructor Detail

FilenameUtils

public FilenameUtils()

Method Detail

getName

public static String getName(String filename)

Gets the name minus the path from a full filename.

This method will handle a file in either Unix or Windows format. The text after the last forward or backslash is returned.

 a/b/c.txt --> c.txt
 a.txt     --> a.txt
 a/b/c     --> c
 a/b/c/    --> ""
 

The output will be the same irrespective of the machine that the code is running on.

Parameters:

filename - the filename to query, null returns null

Returns:

the name of the file without the path, or an empty string if none exists

getBaseName

public static String getBaseName(String filename)

Gets the base name, minus the full path and extension, from a full filename.

This method will handle a file in either Unix or Windows format. The text after the last forward or backslash and before the last dot is returned.

 a/b/c.txt --> c
 a.txt     --> a
 a/b/c     --> c
 a/b/c/    --> ""
 

The output will be the same irrespective of the machine that the code is running on.

Parameters:

filename - the filename to query, null returns null

Returns:

the name of the file without the path, or an empty string if none exists

getExtension

public static String getExtension(String filename)

Gets the extension of a filename.

This method returns the textual part of the filename after the last dot. There must be no directory separator after the dot.

 foo.txt      --> "txt"
 a/b/c.jpg    --> "jpg"
 a/b.txt/c    --> ""
 a/b/c        --> ""
 

The output will be the same irrespective of the machine that the code is running on.

Parameters:

filename - the filename to retrieve the extension of.

Returns:

the extension of the file or an empty string if none exists.

removeExtension

public static String removeExtension(String filename)

Removes the extension from a filename.

This method returns the textual part of the filename before the last dot. There must be no directory separator after the dot.

 foo.txt    --> foo
 a\b\c.jpg  --> a\b\c
 a\b\c      --> a\b\c
 a.b\c      --> a.b\c
 

The output will be the same irrespective of the machine that the code is running on.

Parameters:

filename - the filename to query, null returns null

Returns:

the filename minus the extension

indexOfLastSeparator

public static int indexOfLastSeparator(String filename)

Returns the index of the last directory separator character.

This method will handle a file in either Unix or Windows format. The position of the last forward or backslash is returned.

The output will be the same irrespective of the machine that the code is running on.

Parameters:

filename - the filename to find the last path separator in, null returns -1

Returns:

the index of the last separator character, or -1 if there is no such character

indexOfExtension

public static int indexOfExtension(String filename)

Returns the index of the last extension separator character, which is a dot.

This method also checks that there is no directory separator after the last dot. To do this it uses indexOfLastSeparator(String) which will handle a file in either Unix or Windows format.

The output will be the same irrespective of the machine that the code is running on.

Parameters:

filename - the filename to find the last path separator in, null returns -1

Returns:

the index of the last separator character, or -1 if there is no such character

getFullPath

public static String getFullPath(String filename)

Gets the path from a full filename.

Parameters:

filename - a full filename

Returns:

the path

getFullPathWithEndSeprator

public static String getFullPathWithEndSeprator(String filename)

Gets the path with end separator from a full filename.

Parameters:

filename - a full filename

Returns:

the path

isValidFileExtension

public static boolean isValidFileExtension(String filename,
                                           String allowedFileExtensions,
                                           String deniedFileExtensions)

Checks whether the extension of the filename is valid. The extension check is case-sensitive on all platforms.

Parameters:

filename - he filename to query, null returns false

allowedFileExtensions - the allowed file extensions

deniedFileExtensions - the denied file extensions

Returns:

true, if is valid file extention

seekUniqueFile

public static File seekUniqueFile(File srcFile)
                           throws IOException

Returns a file name that does not overlap in the specified directory. If a duplicate file name exists, it is returned by appending a number after the file name.

Parameters:

srcFile - the file to seek

Returns:

an unique file

Throws:

IOException - if failed to obtain an unique file

seekUniqueFile

public static File seekUniqueFile(File srcFile,
                                  char extSeparator)
                           throws IOException

Returns a file name that does not overlap in the specified directory. If a duplicate file name exists, it is returned by appending a number after the file name.

Parameters:

srcFile - the file to seek

extSeparator - the extension separator

Returns:

an unique file

Throws:

IOException - if failed to obtain an unique file

generateSafetyUniqueFile

public static File generateSafetyUniqueFile(File file)
                                     throws IOException

Creates and returns a safe file name on the system without duplication in the specified directory. If a duplicate file name exists, it is returned by appending a number after the file name. File extensions are separated by '_' character.

 ex) 1111111111_txt
 

Parameters:

file - the file to seek

Returns:

an unique file

Throws:

IOException - if failed to obtain an unique file