org.openimaj.io

Class FileUtils

java.lang.Object

org.openimaj.io.FileUtils

public class FileUtils
extends Object

Utility methods for dealing with files on the filesystem

Author:

Jonathon Hare (jsh2@ecs.soton.ac.uk), Sina Samangooei (ss@ecs.soton.ac.uk), David Dupplaw (dpd@ecs.soton.ac.uk)

Constructor Summary

Constructors

Constructor and Description
FileUtils()

Method Summary

Modifier and Type	Method and Description
static File	copyStreamToFile(InputStream stream, File output) Helper function for writing a text stream to a file.
static File	copyStreamToFileBinary(InputStream stream, File output) Helper function for writing a binary stream to a file.
static int	countLines(File filename) Count the number of newlines in the given file
static boolean	deleteRecursive(File dir) Recursively delete a directory
static void	downloadURL(URL url, File file) Download the contents of the given URL to the given file
static File[]	findRecursive(File start, FilenameFilter filenameFilter) Using File.listFiles(FilenameFilter) find a file in the directory recursively (i.e.
static boolean	isJarResource(String resourceURL) Returns whether the given resource is a jar resource.
static boolean	isJarResource(URL resource) Returns whether the given resource is a jar resource.
static BufferedReader	read(File file) Utility method for quickly create a BufferedReader for a given file.
static String	readall(File file) Utility method for reading a whole file into a single string.
static String	readall(InputStream stream) Utility method for reading a whole file into a single string.
static String	readall(InputStream stream, String encoding) Utility method for reading a whole file into a single string.
static String[]	readlines(File file)
static String[]	readlines(File file, String encoding)
static String[]	readlines(InputStream stream)
static String[]	readlines(InputStream stream, String encoding)
static File	unpackJarFile(URL resource) Given a JAR Resource, this method will unpack the file to a temporary file and return the temporary file location.
static File	unpackJarFile(URL resource, boolean deleteOnExit) Given a JAR Resource, this method will unpack the file to a temporary file and return the temporary file location.
static void	unpackJarFile(URL resource, File destination, boolean deleteOnExit) Given a JAR resource, this method will unpack the file to the given destination.

Methods inherited from class java.lang.Object

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

Constructor Detail

FileUtils

public FileUtils()

Method Detail

deleteRecursive

public static boolean deleteRecursive(File dir)

Recursively delete a directory

Parameters:

dir -

Returns:

true if success; false otherwise

downloadURL

public static void downloadURL(URL url,
                               File file)
                        throws IOException

Download the contents of the given URL to the given file

Parameters:

url - The URL to download from

file - The target file

Throws:

IOException - if an error occurs

read

public static BufferedReader read(File file)
                           throws IOException

Utility method for quickly create a BufferedReader for a given file.

Parameters:

file - The file

Returns:

the corresponding reader

Throws:

IOException - if an error occurs

readall

public static String readall(InputStream stream)
                      throws IOException

Utility method for reading a whole file into a single string.

Parameters:

stream - The stream

Returns:

the corresponding reader

Throws:

IOException - if an error occurs

readall

public static String readall(InputStream stream,
                             String encoding)
                      throws IOException

Utility method for reading a whole file into a single string.

Parameters:

stream - The stream

encoding - the charset of InputStreamReader

Returns:

the corresponding reader

Throws:

IOException - if an error occurs

readall

public static String readall(File file)
                      throws IOException

Utility method for reading a whole file into a single string.

Parameters:

file - The file

Returns:

the corresponding reader

Throws:

IOException - if an error occurs

copyStreamToFile

public static File copyStreamToFile(InputStream stream,
                                    File output)
                             throws IOException

Helper function for writing a text stream to a file.

Parameters:

stream - the stream will be consumed

output - file

Returns:

a temporary file with the stream context written

Throws:

IOException

copyStreamToFileBinary

public static File copyStreamToFileBinary(InputStream stream,
                                          File output)
                                   throws IOException

Helper function for writing a binary stream to a file. The stream and the file are both closed on completion.

Parameters:

stream - The stream to be consumed.

output - The file to output to

Returns:

The output file

Throws:

IOException

unpackJarFile

public static File unpackJarFile(URL resource)
                          throws IOException

Given a JAR Resource, this method will unpack the file to a temporary file and return the temporary file location. This temporary file will be deleted on the application exit. If the given resource is not a JAR resource, the method will return null.

Parameters:

resource - The resource to unpack

Returns:

The temporary file location

Throws:

IOException - If the temporary file could not be created.

unpackJarFile

public static File unpackJarFile(URL resource,
                                 boolean deleteOnExit)
                          throws IOException

Given a JAR Resource, this method will unpack the file to a temporary file and return the temporary file location. If the given resource is not a JAR resource, the method will return null.

Parameters:

resource - The resource to unpack

deleteOnExit - Whether to delete the temporary file on exit

Returns:

The temporary file location

Throws:

IOException - If the temporary file could not be created.

unpackJarFile

public static void unpackJarFile(URL resource,
                                 File destination,
                                 boolean deleteOnExit)

Given a JAR resource, this method will unpack the file to the given destination. If the given resource is not a JAR resource, this method will do nothing.

Parameters:

resource - The resource to unpack.

destination - The destination file

deleteOnExit - Whether to delete the unpacked file on exit.

isJarResource

public static boolean isJarResource(URL resource)

Returns whether the given resource is a jar resource.

Parameters:

resource - The resource to test.

Returns:

TRUE if the resource is a JAR resource

isJarResource

public static boolean isJarResource(String resourceURL)

Returns whether the given resource is a jar resource.

Parameters:

resourceURL - The resource to test.

Returns:

TRUE if the resource is in a jar.

countLines

public static int countLines(File filename)

Count the number of newlines in the given file

Parameters:

filename - The file

Returns:

the number of newline characters

findRecursive

public static File[] findRecursive(File start,
                                   FilenameFilter filenameFilter)

Using File.listFiles(FilenameFilter) find a file in the directory recursively (i.e. following directories down).

Parameters:

start -

filenameFilter -

Returns:

list of files matching the filter

readlines

public static String[] readlines(File file)
                          throws IOException

Parameters:

file - the file to read from

Returns:

the lines in the file

Throws:

IOException

readlines

public static String[] readlines(File file,
                                 String encoding)
                          throws IOException

Parameters:

file - the file to read from

encoding -

Returns:

the lines in the file

Throws:

IOException

readlines

public static String[] readlines(InputStream stream)
                          throws IOException

Parameters:

stream - the file to read from

Returns:

the lines in the file

Throws:

IOException

readlines

public static String[] readlines(InputStream stream,
                                 String encoding)
                          throws IOException

Parameters:

stream - the file to read from

encoding - the inputstream encoding

Returns:

the lines in the file

Throws:

IOException