edu.umass.cs.mallet.base.util

Class FileUtils

java.lang.Object

edu.umass.cs.mallet.base.util.FileUtils

public class FileUtils
extends Object

Contains static utilities for manipulating files. Created: Thu Nov 20 15:14:16 2003

Version:

$Id: FileUtils.java,v 1.2 2005/01/31 00:41:35 casutton Exp $

Author:

Charles Sutton

Method Summary

Modifier and Type	Method and Description
static String[]	readFile(File f) Reads every line from a given text file.
static Object	readGzippedObject(File f) Reads a serialized object from a file that has been compressed using gzip.
static Object	readObject(File f) Reads a Serialized object, which may or may not be zipped.
static Object	readUnzippedObject(File f) Reads a serialized object from a file.
static File	uniqueFile(File dir, String prefix, String extension) Creates a file, making sure that its name is unique.
static void	writeGzippedObject(File f, Serializable obj) Writes a serialized version of obj to a given file, compressing it using gzip.
static void	writeObject(File f, Serializable obj) Serializes an object to a file, masking out annoying exceptions.

Methods inherited from class java.lang.Object

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

Method Detail

writeObject

public static void writeObject(File f,
                               Serializable obj)

Serializes an object to a file, masking out annoying exceptions. Any IO exceptions are caught, and printed to standard error. Consider using writeGzippedObject(java.io.File, java.io.Serializable) instead, for that method will compress the serialized file, and it'll still be reaoable by readObject(java.io.File).

Parameters:

f - File to write to

obj - Object to serialize

See Also:

writeGzippedObject(java.io.File, java.io.Serializable)

readObject

public static Object readObject(File f)

Reads a Serialized object, which may or may not be zipped. Guesses from the file name whether to decompress or not.

Parameters:

f - File to read data from

Returns:

A deserialized object.

readUnzippedObject

public static Object readUnzippedObject(File f)

Reads a serialized object from a file. You probably want to use readObject(java.io.File) instead, because that method will automatically guess from the extension whether the file is compressed, and call this method if necessary.

Parameters:

f - File to read object from

See Also:

readObject(java.io.File)

readFile

public static String[] readFile(File f)
                         throws IOException

Reads every line from a given text file.

Parameters:

f - Input file.

Returns:

String[] Array containing each line in f.

Throws:

IOException

uniqueFile

public static File uniqueFile(File dir,
                              String prefix,
                              String extension)
                       throws IOException

Creates a file, making sure that its name is unique. The file will be created as if by new File(dir, prefix+i+extension), where i is an integer chosen such that the returned File does not exist.

Parameters:

dir - Directory to use for the returned file

prefix - Prefix of the file name (before the uniquifying integer)

extension - Suffix of the file name (after the uniquifying integer)

Throws:

IOException

writeGzippedObject

public static void writeGzippedObject(File f,
                                      Serializable obj)

Writes a serialized version of obj to a given file, compressing it using gzip.

Parameters:

f - File to write to

obj - Object to serialize

readGzippedObject

public static Object readGzippedObject(File f)

Reads a serialized object from a file that has been compressed using gzip. You probably want to use readObject(java.io.File) instead, because it will automatically guess from the extension whether the file is compressed, and call this method if necessary.

Parameters:

f - Compressed file to read object from

See Also:

readObject(java.io.File)