org.apache.commons.io.output

类 LockableFileWriter

java.lang.Object

java.io.Writer

org.apache.commons.io.output.LockableFileWriter

所有已实现的接口:

Closeable, Flushable, Appendable, AutoCloseable

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.

N.B. the lock file is deleted when close() is called - or if the main file cannot be opened initially. In the (unlikely) event that the lockfile cannot be deleted, this is not reported, and subsequent requests using the same lockfile will fail.

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.

字段概要

从类继承的字段 java.io.Writer

lock

构造器概要

构造器

构造器和说明
LockableFileWriter(File file) Constructs a LockableFileWriter.
LockableFileWriter(File file, boolean append) Constructs a LockableFileWriter.
LockableFileWriter(File file, boolean append, String lockDir) 已过时。 2.5 use LockableFileWriter(File, Charset, boolean, String) instead
LockableFileWriter(File file, Charset encoding) Constructs a LockableFileWriter with a file encoding.
LockableFileWriter(File file, Charset encoding, boolean append, String lockDir) Constructs a LockableFileWriter with a file encoding.
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.

方法概要

限定符和类型	方法和说明
void	close() Closes the file writer and deletes the lockfile (if possible).
void	flush() Flush the stream.
void	write(char[] chr) Write the characters from an array.
void	write(char[] chr, int st, int end) Write the specified characters from an array.
void	write(int idx) Write a character.
void	write(String str) Write the characters from a string.
void	write(String str, int st, int end) Write the specified characters from a string.

从类继承的方法 java.io.Writer

append, append, append

从类继承的方法 java.lang.Object

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

构造器详细资料

LockableFileWriter

public LockableFileWriter(String fileName)
                   throws IOException

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

参数:

fileName - the file to write to, not null

抛出:

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.

参数:

fileName - file to write to, not null

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

抛出:

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.

参数:

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

抛出:

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.

参数:

file - the file to write to, not null

抛出:

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.

参数:

file - the file to write to, not null

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

抛出:

NullPointerException - if the file is null

IOException - in case of an I/O error

LockableFileWriter

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

已过时。 2.5 use LockableFileWriter(File, Charset, boolean, String) instead

Constructs a LockableFileWriter.

参数:

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

抛出:

NullPointerException - if the file is null

IOException - in case of an I/O error

LockableFileWriter

public LockableFileWriter(File file,
                          Charset encoding)
                   throws IOException

Constructs a LockableFileWriter with a file encoding.

参数:

file - the file to write to, not null

encoding - the encoding to use, null means platform default

抛出:

NullPointerException - if the file is null

IOException - in case of an I/O error

从以下版本开始:

2.3

LockableFileWriter

public LockableFileWriter(File file,
                          String encoding)
                   throws IOException

Constructs a LockableFileWriter with a file encoding.

参数:

file - the file to write to, not null

encoding - the encoding to use, null means platform default

抛出:

NullPointerException - if the file is null

IOException - in case of an I/O error

UnsupportedCharsetException - thrown instead of UnsupportedEncodingException in version 2.2 if the encoding is not supported.

LockableFileWriter

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

Constructs a LockableFileWriter with a file encoding.

参数:

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

抛出:

NullPointerException - if the file is null

IOException - in case of an I/O error

从以下版本开始:

2.3

LockableFileWriter

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

Constructs a LockableFileWriter with a file encoding.

参数:

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

抛出:

NullPointerException - if the file is null

IOException - in case of an I/O error

UnsupportedCharsetException - thrown instead of UnsupportedEncodingException in version 2.2 if the encoding is not supported.

方法详细资料

close

public void close()
           throws IOException

Closes the file writer and deletes the lockfile (if possible).

指定者:

close 在接口中 Closeable

指定者:

close 在接口中 AutoCloseable

指定者:

close 在类中 Writer

抛出:

IOException - if an I/O error occurs

write

public void write(int idx)
           throws IOException

Write a character.

覆盖:

write 在类中 Writer

参数:

idx - the character to write

抛出:

IOException - if an I/O error occurs

write

public void write(char[] chr)
           throws IOException

Write the characters from an array.

覆盖:

write 在类中 Writer

参数:

chr - the characters to write

抛出:

IOException - if an I/O error occurs

write

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

Write the specified characters from an array.

指定者:

write 在类中 Writer

参数:

chr - the characters to write

st - The start offset

end - The number of characters to write

抛出:

IOException - if an I/O error occurs

write

public void write(String str)
           throws IOException

Write the characters from a string.

覆盖:

write 在类中 Writer

参数:

str - the string to write

抛出:

IOException - if an I/O error occurs

write

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

Write the specified characters from a string.

覆盖:

write 在类中 Writer

参数:

str - the string to write

st - The start offset

end - The number of characters to write

抛出:

IOException - if an I/O error occurs

flush

public void flush()
           throws IOException

Flush the stream.

指定者:

flush 在接口中 Flushable

指定者:

flush 在类中 Writer

抛出:

IOException - if an I/O error occurs