Package nl.rrd.wool.utils

Class FileUtils

java.lang.Object

nl.rrd.wool.utils.FileUtils

public class FileUtils
extends Object

This class contains utility methods related to the file system.

Constructor Summary

Constructors

Constructor	Description
FileUtils()

Method Summary

Modifier and Type	Method	Description
static void	clearDirectory(File dir)	Deletes the content of the specified directory.
static void	copyFile(File source, File dest)	Copies the specified source file to the specified destination file.
static void	copyFile(File source, File dest, long start, long len)	Copies bytes from the specified source file to the specified destination file.
static File	createTempFile(File dir, String prefix, String ext)	Creates a temporary file in the specified directory.
static void	deleteTree(File dir)	Deletes the specified directory including all its contents.
static void	downloadFile(URL source, File dest)
static void	mkdir(File dir)	Creates the specified directory and all non-existing parent directories.
static byte[]	readFileBytes(File file)	Reads the content of the specified file as a byte array.
static byte[]	readFileBytes(InputStream input)	Reads the content of the specified file as a byte array.
static byte[]	readFileBytes(URL url)	Reads the content of the specified file as a byte array.
static String	readFileString(File file)	Reads the content of the specified file as a string.
static String	readFileString(InputStream input)	Reads the content of the specified file as a string.
static String	readFileString(Reader reader)	Reads the content of the specified file as a string.
static String	readFileString(URL url)	Reads the content of the specified file as a string.
static void	truncate(File file, long len)	Truncates the specified file so it won't be longer than the specified length.
static void	writeFileString(File file, String content)	Writes a string to a file with encoding UTF-8.
static void	writeFileString(OutputStream output, String content)	Writes a string to an output stream with encoding UTF-8.

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

mkdir

public static void mkdir(File dir)
                  throws IOException

Creates the specified directory and all non-existing parent directories.

Parameters:

dir - the directory

Throws:

IOException - if the directory can't be created

truncate

public static void truncate(File file,
                            long len)
                     throws IOException

Truncates the specified file so it won't be longer than the specified length. This method will copy the file to a temporary file and then copy back at most "len" bytes.

Parameters:

file - the file

len - the length

Throws:

IOException - if a reading/writing error occurs

createTempFile

public static File createTempFile(File dir,
                                  String prefix,
                                  String ext)
                           throws IOException

Creates a temporary file in the specified directory. The file name will be formatted as "prefix.number.ext", where number is a sequence of eight hexadecimal digits. This method will use a file name that doesn't already exist and it atomically creates an empty file with that name.

Parameters:

dir - the directory

prefix - the prefix

ext - the extension

Returns:

the file

Throws:

IOException - if a writing error occurs

copyFile

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

Copies the specified source file to the specified destination file.

Parameters:

source - the source file

dest - the destination file

Throws:

IOException - if a read/write error occurs

copyFile

public static void copyFile(File source,
                            File dest,
                            long start,
                            long len)
                     throws IOException

Copies bytes from the specified source file to the specified destination file.

Parameters:

source - the source file

dest - the destination file

start - the index of the first byte to copy

len - the number of bytes to copy

Throws:

IOException - if a read/write error occurs

downloadFile

public static void downloadFile(URL source,
                                File dest)
                         throws IOException

Throws:

IOException

deleteTree

public static void deleteTree(File dir)
                       throws IOException

Deletes the specified directory including all its contents. If dir is a file, it will just delete that file.

Parameters:

dir - the directory or file

Throws:

IOException - if a file or directory can't be deleted

clearDirectory

public static void clearDirectory(File dir)
                           throws IOException

Deletes the content of the specified directory. If the directory doesn't exist, this method has no effect.

Parameters:

dir - the directory

Throws:

IOException - if the specified path is not a directory or if a file or directory can't be deleted

readFileBytes

public static byte[] readFileBytes(File file)
                            throws IOException

Reads the content of the specified file as a byte array.

Parameters:

file - the file

Returns:

the content

Throws:

IOException - if a reading error occurs

readFileBytes

public static byte[] readFileBytes(URL url)
                            throws IOException

Reads the content of the specified file as a byte array.

Parameters:

url - the URL for the file

Returns:

the content

Throws:

IOException - if a reading error occurs

readFileBytes

public static byte[] readFileBytes(InputStream input)
                            throws IOException

Reads the content of the specified file as a byte array.

Parameters:

input - the input stream from the file

Returns:

the content

Throws:

IOException - if a reading error occurs

readFileString

public static String readFileString(File file)
                             throws IOException

Reads the content of the specified file as a string. It assumes character encoding UTF-8.

Parameters:

file - the file

Returns:

the content

Throws:

IOException - if a reading error occurs

readFileString

public static String readFileString(URL url)
                             throws IOException

Reads the content of the specified file as a string. It assumes character encoding UTF-8.

Parameters:

url - the URL for the file

Returns:

the content

Throws:

IOException - if a reading error occurs

readFileString

public static String readFileString(InputStream input)
                             throws IOException

Reads the content of the specified file as a string. It assumes character encoding UTF-8.

Parameters:

input - the input stream from the file

Returns:

the content

Throws:

IOException - if a reading error occurs

readFileString

public static String readFileString(Reader reader)
                             throws IOException

Reads the content of the specified file as a string.

Parameters:

reader - the reader from the file

Returns:

the content

Throws:

IOException - if a reading error occurs

writeFileString

public static void writeFileString(File file,
                                   String content)
                            throws IOException

Writes a string to a file with encoding UTF-8.

Parameters:

file - the file

content - the content string to write

Throws:

IOException - if a writing error occurs

writeFileString

public static void writeFileString(OutputStream output,
                                   String content)
                            throws IOException

Writes a string to an output stream with encoding UTF-8.

Parameters:

output - the output stream

content - the content string to write

Throws:

IOException - if a writing error occurs