gov.lbl.dsd.p2pio.util
Class FileUtils

java.lang.Object
  gov.lbl.dsd.p2pio.util.FileUtils

public class FileUtils

extends Object

Field Summary

static int	ONE_GB The number of bytes in a gigabyte.
static int	ONE_KB The number of bytes in a kilobyte.
static int	ONE_MB The number of bytes in a megabyte.

Method Summary

static String	basename(String filename) Returns the filename portion of a file specification string.
static String	basename(String filename, String suffix) Returns the filename portion of a file specification string.
static String	byteCountToDisplaySize(int size) Returns a human-readable version of the file size (original is in bytes).
static String	catPath(String lookupPath, String path) Will concatenate 2 paths.
static void	cleanDirectory(File directory) Clean a directory without deleting it.
static void	cleanDirectory(String directory) Clean a directory without deleting it.
static boolean	contentEquals(File file1, File file2) Compare the contents of two files to determine if they are equal or not.
static void	copyFile(File source, File destination) Copy file from source to destination.
static void	copyFileToDirectory(File source, File destinationDirectory) Copy file from source to destination.
static void	copyFileToDirectory(String source, String destinationDirectory) Copy file from source to destination.
static void	copyURLToFile(URL source, File destination) Copies bytes from the URL source to a file destination.
static void	deleteDirectory(File directory) Recursively delete a directory.
static void	deleteDirectory(String directory) Recursively delete a directory.
static String	dirname(String filename) Returns the directory path portion of a file specification string.
static String	extension(String filename) Returns the extension portion of a file specification string.
static void	fileCopy(String inFileName, String outFileName) Copy a file.
static void	fileDelete(String fileName) Deletes a file.
static boolean	fileExists(String fileName) Check if a file exits.
static String	filename(String filename) Returns the filename portion of a file specification string.
static String	fileRead(String fileName) Reads the contents of a file.
static void	fileWrite(String fileName, String data) Writes data to a file.
static void	forceDelete(File file) Delete a file.
static void	forceDelete(String file) Delete a file.
static void	forceDeleteOnExit(File file) Schedule a file to be deleted when JVM exits.
static void	forceMkdir(File file) Make a directory.
static String	getExtension(String filename) Get extension from filename.
static File	getFile(String fileName) Creates a file handle.
static String[]	getFilesFromExtension(String directory, String[] extensions) Given a directory and an array of extensions...
static String	getPath(String filepath) Get path from filename.
static String	getPath(String filepath, char fileSeparatorChar) Get path from filename.
static void	mkdir(String dir) Simple way to make a directory
static String	normalize(String path) Normalize a path.
static String	removeExtension(String filename) Remove extension from filename.
static String	removePath(String filepath) Remove path from filename.
static String	removePath(String filepath, char fileSeparatorChar) Remove path from filename.
static File	resolveFile(File baseFile, String filename) Resolve a file filename to it's canonical form.
static long	sizeOfDirectory(File directory) Recursively count size of a directory.
static long	sizeOfDirectory(String directory) Recursively count size of a directory.
static File	toFile(URL url) Convert from a URL to a File.
static URL[]	toURLs(File[] files) Convert the array of Files into a list of URLs.
static boolean	waitFor(String fileName, int seconds) Waits for NFS to propagate a file creation, imposing a timeout.

Methods inherited from class java.lang.Object

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

Field Detail

ONE_KB

public static final int ONE_KB

The number of bytes in a kilobyte.

See Also:

Constant Field Values

ONE_MB

public static final int ONE_MB

The number of bytes in a megabyte.

See Also:

Constant Field Values

ONE_GB

public static final int ONE_GB

The number of bytes in a gigabyte.

See Also:

Constant Field Values

Method Detail

byteCountToDisplaySize

public static String byteCountToDisplaySize(int size)

Returns a human-readable version of the file size (original is in bytes).

Parameters:

size - The number of bytes.

Returns:

A human-readable display value (includes units).

dirname

public static String dirname(String filename)

Returns the directory path portion of a file specification string. Matches the equally named unix command.

Returns:

The directory portion excluding the ending file separator.

filename

public static String filename(String filename)

Returns the filename portion of a file specification string.

Returns:

The filename string with extension.

basename

public static String basename(String filename)

Returns the filename portion of a file specification string. Matches the equally named unix command.

Returns:

The filename string without extension.

basename

public static String basename(String filename,
                              String suffix)

Returns the filename portion of a file specification string. Matches the equally named unix command.

extension

public static String extension(String filename)

Returns the extension portion of a file specification string. This everything after the last dot '.' in the filename (NOT including the dot).

fileExists

public static boolean fileExists(String fileName)

Check if a file exits.

Parameters:

fileName - The name of the file to check.

Returns:

true if file exists.

fileRead

public static String fileRead(String fileName)
                       throws IOException

Reads the contents of a file.

Parameters:

fileName - The name of the file to read.

Returns:

The file contents or null if read failed.

Throws:

IOException

fileWrite

public static void fileWrite(String fileName,
                             String data)
                      throws Exception

Writes data to a file. The file will be created if it does not exist.

Parameters:

fileName - The name of the file to write.

data - The content to write to the file.

Throws:

Exception

fileCopy

public static void fileCopy(String inFileName,
                            String outFileName)
                     throws Exception

Copy a file. The new file will be created if it does not exist. This is an inefficient method, which just calls fileRead(String) and then fileWrite(String,String)

Parameters:

inFileName - the file to copy

outFileName - the file to copy to

Throws:

Exception - if fileRead or fileWrite throw it

fileDelete

public static void fileDelete(String fileName)

Deletes a file.

Parameters:

fileName - The name of the file to delete.

waitFor

public static boolean waitFor(String fileName,
                              int seconds)

Waits for NFS to propagate a file creation, imposing a timeout.

Parameters:

fileName - The name of the file.

seconds - The maximum time in seconds to wait.

Returns:

True if file exists.

getFile

public static File getFile(String fileName)

Creates a file handle.

Parameters:

fileName - The name of the file.

Returns:

A File instance.

getFilesFromExtension

public static String[] getFilesFromExtension(String directory,
                                             String[] extensions)

Given a directory and an array of extensions... return an array of compliant files. TODO Should an ignore list be passed in? TODO Should a recurse flag be passed in? The given extensions should be like "java" and not like ".java"

mkdir

public static void mkdir(String dir)

Simple way to make a directory

contentEquals

public static boolean contentEquals(File file1,
                                    File file2)
                             throws IOException

Compare the contents of two files to determine if they are equal or not.

Parameters:

file1 - the first file

file2 - the second file

Returns:

true if the content of the files are equal or they both don't exist, false otherwise

Throws:

IOException

toFile

public static File toFile(URL url)

Convert from a URL to a File.

Parameters:

url - File URL.

Returns:

The equivalent File object, or null if the URL's protocol is not file

toURLs

public static URL[] toURLs(File[] files)
                    throws IOException

Convert the array of Files into a list of URLs.

Parameters:

files - the array of files

Returns:

the array of URLs

Throws:

IOException - if an error occurs

removeExtension

public static String removeExtension(String filename)

Remove extension from filename. ie

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

Parameters:

filename - the filename

Returns:

the filename minus extension

getExtension

public static String getExtension(String filename)

Get extension from filename. ie

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

Parameters:

filename - the filename

Returns:

the extension of filename or "" if none

removePath

public static String removePath(String filepath)

Remove path from filename. Equivalent to the unix command basename ie.

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

Parameters:

filepath - the filepath

Returns:

the filename minus path

removePath

public static String removePath(String filepath,
                                char fileSeparatorChar)

Remove path from filename. ie.

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

Parameters:

filepath - the filepath

Returns:

the filename minus path

getPath

public static String getPath(String filepath)

Get path from filename. Roughly equivalent to the unix command dirname. ie.

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

Parameters:

filepath - the filepath

Returns:

the filename minus path

getPath

public static String getPath(String filepath,
                             char fileSeparatorChar)

Get path from filename. ie.

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

Parameters:

filepath - the filepath

Returns:

the filename minus path

copyFileToDirectory

public static void copyFileToDirectory(String source,
                                       String destinationDirectory)
                                throws IOException

Copy file from source to destination. If destinationDirectory does not exist, it (and any parent directories) will be created. If a file source in destinationDirectory exists, it will be overwritten.

Parameters:

source - An existing File to copy.

destinationDirectory - A directory to copy source into.

Throws:

FileNotFoundException - if source isn't a normal file.

IllegalArgumentException - if destinationDirectory isn't a directory.

IOException - if source does not exist, the file in destinationDirectory cannot be written to, or an IO error occurs during copying.

copyFileToDirectory

public static void copyFileToDirectory(File source,
                                       File destinationDirectory)
                                throws IOException

Copy file from source to destination. If destinationDirectory does not exist, it (and any parent directories) will be created. If a file source in destinationDirectory exists, it will be overwritten.

Parameters:

source - An existing File to copy.

destinationDirectory - A directory to copy source into.

Throws:

FileNotFoundException - if source isn't a normal file.

IllegalArgumentException - if destinationDirectory isn't a directory.

IOException - if source does not exist, the file in destinationDirectory cannot be written to, or an IO error occurs during copying.

copyFile

public static void copyFile(File source,
                            File destination)
                     throws IOException

Copy file from source to destination. The directories up to destination will be created if they don't already exist. destination will be overwritten if it already exists.

Parameters:

source - An existing non-directory File to copy bytes from.

destination - A non-directory File to write bytes to (possibly overwriting).

Throws:

IOException - if source does not exist, destination cannot be written to, or an IO error occurs during copying.

FileNotFoundException - if destination is a directory (use copyFileToDirectory(java.lang.String, java.lang.String)).

copyURLToFile

public static void copyURLToFile(URL source,
                                 File destination)
                          throws IOException

Copies bytes from the URL source to a file destination. The directories up to destination will be created if they don't already exist. destination will be overwritten if it already exists.

Parameters:

source - A URL to copy bytes from.

destination - A non-directory File to write bytes to (possibly overwriting).

Throws:

IOException - if

• source URL cannot be opened
• destination cannot be written to
• an IO error occurs during copying

normalize

public static String normalize(String path)

Normalize a path. Eliminates "/../" and "/./" in a string. Returns null if the ..'s went past the root. Eg:

 /foo//               -->     /foo/
 /foo/./              -->     /foo/
 /foo/../bar          -->     /bar
 /foo/../bar/         -->     /bar/
 /foo/../bar/../baz   -->     /baz
 //foo//./bar         -->     /foo/bar
 /../                 -->     null
 

Parameters:

path - the path to normalize

Returns:

the normalized String, or null if too many ..'s.

catPath

public static String catPath(String lookupPath,
                             String path)

Will concatenate 2 paths. Paths with .. will be properly handled.

Eg.,
/a/b/c + d = /a/b/d
/a/b/c + ../d = /a/d

Thieved from Tomcat sources...

Returns:

The concatenated paths, or null if error occurs

resolveFile

public static File resolveFile(File baseFile,
                               String filename)

Resolve a file filename to it's canonical form. If filename is relative (doesn't start with /), it will be resolved relative to baseFile, otherwise it is treated as a normal root-relative path.

Parameters:

baseFile - Where to resolve filename from, if filename is relative.

filename - Absolute or relative file path to resolve.

Returns:

The canonical File of filename.

forceDelete

public static void forceDelete(String file)
                        throws IOException

Delete a file. If file is directory delete it and all sub-directories.

Throws:

IOException

forceDelete

public static void forceDelete(File file)
                        throws IOException

Delete a file. If file is directory delete it and all sub-directories.

Throws:

IOException

forceDeleteOnExit

public static void forceDeleteOnExit(File file)
                              throws IOException

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

Throws:

IOException

forceMkdir

public static void forceMkdir(File file)
                       throws IOException

Make a directory. If there already exists a file with specified name or the directory is unable to be created then an exception is thrown.

Throws:

IOException

deleteDirectory

public static void deleteDirectory(String directory)
                            throws IOException

Recursively delete a directory.

Throws:

IOException

deleteDirectory

public static void deleteDirectory(File directory)
                            throws IOException

Recursively delete a directory.

Throws:

IOException

cleanDirectory

public static void cleanDirectory(String directory)
                           throws IOException

Clean a directory without deleting it.

Throws:

IOException

cleanDirectory

public static void cleanDirectory(File directory)
                           throws IOException

Clean a directory without deleting it.

Throws:

IOException

sizeOfDirectory

public static long sizeOfDirectory(String directory)

Recursively count size of a directory.

Returns:

size of directory in bytes.

sizeOfDirectory

public static long sizeOfDirectory(File directory)

Recursively count size of a directory.

Returns:

size of directory in bytes.