Javadoc: LockableFileWriter (Apache Commons IO 2.11.0 API)

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

All Implemented Interfaces:

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.

Note: The lock file is deleted when close() is called - or if the main file cannot be opened initially. In the (unlikely) event that the lock file cannot be deleted, an exception is thrown.

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.

Field Summary
- Fields inherited from class java.io.Writer
  lock

Constructor Summary

Constructors
Constructor and Description
`LockableFileWriter(File file)` Constructs a LockableFileWriter.
`LockableFileWriter(File file, boolean append)` Constructs a LockableFileWriter.
`LockableFileWriter(File file, boolean append, String lockDir)` Deprecated. 2.5 use `LockableFileWriter(File, Charset, boolean, String)` instead
`LockableFileWriter(File file, Charset charset)` Constructs a LockableFileWriter with a file encoding.
`LockableFileWriter(File file, Charset charset, boolean append, String lockDir)` Constructs a LockableFileWriter with a file encoding.
`LockableFileWriter(File file, String charsetName)` Constructs a LockableFileWriter with a file encoding.
`LockableFileWriter(File file, String charsetName, 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

All Methods Instance Methods Concrete Methods
Modifier and Type	Method and Description
`void`	`close()` Closes the file writer and deletes the lock file.
`void`	`flush()` Flushes the stream.
`void`	`write(char[] cbuf)` Writes the characters from an array.
`void`	`write(char[] cbuf, int off, int len)` Writes the specified characters from an array.
`void`	`write(int c)` Writes a character.
`void`	`write(String str)` Writes the characters from a string.
`void`	`write(String str, int off, int len)` Writes the specified characters from a string.

Methods inherited from class java.io.Writer
append, append, append

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
```
@Deprecated
public LockableFileWriter(File file,
                                      boolean append,
                                      String lockDir)
                               throws IOException
```
    Deprecated. 2.5 use LockableFileWriter(File, Charset, boolean, String) instead
    
    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,
                          Charset charset)
                   throws IOException
```
    Constructs a LockableFileWriter with a file encoding.
    
    Parameters:
    
    file - the file to write to, not null
    
    charset - the charset to use, null means platform default
    
    Throws:
    
    NullPointerException - if the file is null
    
    IOException - in case of an I/O error
    
    Since:
    
    2.3
  - LockableFileWriter
```
public LockableFileWriter(File file,
                          String charsetName)
                   throws IOException
```
    Constructs a LockableFileWriter with a file encoding.
    
    Parameters:
    
    file - the file to write to, not null
    
    charsetName - the name of the requested charset, null means platform default
    
    Throws:
    
    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 charset,
                          boolean append,
                          String lockDir)
                   throws IOException
```
    Constructs a LockableFileWriter with a file encoding.
    
    Parameters:
    
    file - the file to write to, not null
    
    charset - the name of the requested charset, 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
    
    Since:
    
    2.3
  - LockableFileWriter
```
public LockableFileWriter(File file,
                          String charsetName,
                          boolean append,
                          String lockDir)
                   throws IOException
```
    Constructs a LockableFileWriter with a file encoding.
    
    Parameters:
    
    file - the file to write to, not null
    
    charsetName - 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
    
    UnsupportedCharsetException - thrown instead of UnsupportedEncodingException in version 2.2 if the encoding is not supported.
- Method Detail
  - close
```
public void close()
           throws IOException
```
    Closes the file writer and deletes the lock file.
    
    Specified by:
    
    close in interface Closeable
    
    Specified by:
    
    close in interface AutoCloseable
    
    Specified by:
    
    close in class Writer
    
    Throws:
    
    IOException - if an I/O error occurs.
  - write
```
public void write(int c)
           throws IOException
```
    Writes a character.
    
    Overrides:
    
    write in class Writer
    
    Parameters:
    
    c - the character to write
    
    Throws:
    
    IOException - if an I/O error occurs.
  - write
```
public void write(char[] cbuf)
           throws IOException
```
    Writes the characters from an array.
    
    Overrides:
    
    write in class Writer
    
    Parameters:
    
    cbuf - the characters to write
    
    Throws:
    
    IOException - if an I/O error occurs.
  - write
```
public void write(char[] cbuf,
                  int off,
                  int len)
           throws IOException
```
    Writes the specified characters from an array.
    
    Specified by:
    
    write in class Writer
    
    Parameters:
    
    cbuf - the characters to write
    
    off - The start offset
    
    len - The number of characters to write
    
    Throws:
    
    IOException - if an I/O error occurs.
  - write
```
public void write(String str)
           throws IOException
```
    Writes the characters from a string.
    
    Overrides:
    
    write in class Writer
    
    Parameters:
    
    str - the string to write
    
    Throws:
    
    IOException - if an I/O error occurs.
  - write
```
public void write(String str,
                  int off,
                  int len)
           throws IOException
```
    Writes the specified characters from a string.
    
    Overrides:
    
    write in class Writer
    
    Parameters:
    
    str - the string to write
    
    off - The start offset
    
    len - The number of characters to write
    
    Throws:
    
    IOException - if an I/O error occurs.
  - flush
```
public void flush()
           throws IOException
```
    Flushes the stream.
    
    Specified by:
    
    flush in interface Flushable
    
    Specified by:
    
    flush in class Writer
    
    Throws:
    
    IOException - if an I/O error occurs.

Group Id	commons-io
Artifact Id	commons-io
Version	2.11.0
Last Release	2.11.0
Navigation	Index Tree Use Deprecated Help
Last Updated	2021-07-10

Class LockableFileWriter

Field Summary

Fields inherited from class java.io.Writer

Constructor Summary

Method Summary

Methods inherited from class java.io.Writer

Methods inherited from class java.lang.Object

Constructor Detail

LockableFileWriter

LockableFileWriter

LockableFileWriter

LockableFileWriter

LockableFileWriter

LockableFileWriter

LockableFileWriter

LockableFileWriter

LockableFileWriter

LockableFileWriter

Method Detail

close

write

write

write

write

write

flush