org.apache.commons.io.output
Class LockableFileWriter

java.lang.Object
  java.io.Writer
      org.apache.commons.io.output.LockableFileWriter

public class LockableFileWriter

extends Writer

FileWriter that will create and honor lock files to allow simple cross thread file lock handling.

This class provides a simple alternative to FileWriter that will use a lock file to prevent duplicate writes.

By default, the file will be overwritten, but this may be changed to append. The lock directory may be specified, but defaults to the system property java.io.tmpdir. The encoding may also be specified, and defaults to the platform default.

Version:

$Id: LockableFileWriter.java 385293 2006-03-12 15:11:19Z scolebourne $

Field Summary

Fields inherited from class java.io.Writer

lock

Constructor Summary

LockableFileWriter(File file)
Constructs a LockableFileWriter.

LockableFileWriter(File file, boolean append)
Constructs a LockableFileWriter.

LockableFileWriter(File file, boolean append, String lockDir)
Constructs a LockableFileWriter.

LockableFileWriter(File file, String encoding)
Constructs a LockableFileWriter with a file encoding.

LockableFileWriter(File file, String encoding, boolean append, String lockDir)
Constructs a LockableFileWriter with a file encoding.

LockableFileWriter(String fileName)
Constructs a LockableFileWriter.

LockableFileWriter(String fileName, boolean append)
Constructs a LockableFileWriter.

LockableFileWriter(String fileName, boolean append, String lockDir)
Constructs a LockableFileWriter.

Method Summary

void	close() Closes the file writer.
void	flush()
void	write(char[] chr)
void	write(char[] chr, int st, int end)
void	write(int idx)
void	write(String str)
void	write(String str, int st, int end)

Methods inherited from class java.lang.Object

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

Constructor Detail

LockableFileWriter

public LockableFileWriter(String fileName)
                   throws IOException

Constructs a LockableFileWriter. If the file exists, it is overwritten.

Parameters:

fileName - the file to write to, not null

Throws:

NullPointerException - if the file is null

IOException - in case of an I/O error

LockableFileWriter

public LockableFileWriter(String fileName,
                          boolean append)
                   throws IOException

Constructs a LockableFileWriter.

Parameters:

fileName - file to write to, not null

append - true if content should be appended, false to overwrite

Throws:

NullPointerException - if the file is null

IOException - in case of an I/O error

LockableFileWriter

public LockableFileWriter(String fileName,
                          boolean append,
                          String lockDir)
                   throws IOException

Constructs a LockableFileWriter.

Parameters:

fileName - the file to write to, not null

append - true if content should be appended, false to overwrite

lockDir - the directory in which the lock file should be held

Throws:

NullPointerException - if the file is null

IOException - in case of an I/O error

LockableFileWriter

public LockableFileWriter(File file)
                   throws IOException

Constructs a LockableFileWriter. If the file exists, it is overwritten.

Parameters:

file - the file to write to, not null

Throws:

NullPointerException - if the file is null

IOException - in case of an I/O error

LockableFileWriter

public LockableFileWriter(File file,
                          boolean append)
                   throws IOException

Constructs a LockableFileWriter.

Parameters:

file - the file to write to, not null

append - true if content should be appended, false to overwrite

Throws:

NullPointerException - if the file is null

IOException - in case of an I/O error

LockableFileWriter

public LockableFileWriter(File file,
                          boolean append,
                          String lockDir)
                   throws IOException

Constructs a LockableFileWriter.

Parameters:

file - the file to write to, not null

append - true if content should be appended, false to overwrite

lockDir - the directory in which the lock file should be held

Throws:

NullPointerException - if the file is null

IOException - in case of an I/O error

LockableFileWriter

public LockableFileWriter(File file,
                          String encoding)
                   throws IOException

Constructs a LockableFileWriter with a file encoding.

Parameters:

file - the file to write to, not null

encoding - the encoding to use, null means platform default

Throws:

NullPointerException - if the file is null

IOException - in case of an I/O error

LockableFileWriter

public LockableFileWriter(File file,
                          String encoding,
                          boolean append,
                          String lockDir)
                   throws IOException

Constructs a LockableFileWriter with a file encoding.

Parameters:

file - the file to write to, not null

encoding - the encoding to use, null means platform default

append - true if content should be appended, false to overwrite

lockDir - the directory in which the lock file should be held

Throws:

NullPointerException - if the file is null

IOException - in case of an I/O error

Method Detail

close

public void close()
           throws IOException

Closes the file writer.

Throws:

IOException - if an I/O error occurs

write

public void write(int idx)
           throws IOException

Throws:

IOException

See Also:

Writer.write(int)

write

public void write(char[] chr)
           throws IOException

Throws:

IOException

See Also:

Writer.write(char[])

write

public void write(char[] chr,
                  int st,
                  int end)
           throws IOException

Throws:

IOException

See Also:

Writer.write(char[], int, int)

write

public void write(String str)
           throws IOException

Throws:

IOException

See Also:

Writer.write(String)

write

public void write(String str,
                  int st,
                  int end)
           throws IOException

Throws:

IOException

See Also:

Writer.write(String, int, int)

flush

public void flush()
           throws IOException

Throws:

IOException

See Also:

Writer.flush()