Summary: Ctors | Methods | Inherited Methods | [Expand All]

public class

FileHandler

extends StreamHandler

java.lang.Object
↳	java.util.logging.Handler
	↳	java.util.logging.StreamHandler
		↳	java.util.logging.FileHandler

Class Overview

A Handler writes description of logging event into a specified file or a rotating set of files.

If a set of files are used, when a given amount of data has been written to one file, this file is closed, and another file is opened. The name of these files are generated by given name pattern, see below for details.

By default the IO buffering mechanism is enabled, but when each log record is complete, it is flushed out.

XMLFormatter is default formatter for FileHandler.

MemoryHandler will read following LogManager properties for initialization, if given properties are not defined or has invalid values, default value will be used.

java.util.logging.FileHandler.level specifies the level for this Handler, defaults to Level.ALL.
java.util.logging.FileHandler.filter specifies the Filter class name, defaults to no Filter.
java.util.logging.FileHandler.formatter specifies the Formatter class, defaults to java.util.logging.XMLFormatter.
java.util.logging.FileHandler.encoding specifies the character set encoding name, defaults to the default platform encoding.
java.util.logging.FileHandler.limit specifies an maximum bytes to write to any one file, defaults to zero, which means no limit.
java.util.logging.FileHandler.count specifies how many output files to rotate, defaults to 1.
java.util.logging.FileHandler.pattern specifies name pattern for the output files. See below for details. Defaults to "%h/java%u.log".
java.util.logging.FileHandler.append specifies whether this FileHandler should append onto existing files, defaults to false.

Name pattern is a string that may includes some special sub-strings, which will be replaced to generate output files:

"/" represents the local pathname separator
"%t" represents the system temporary directory
"%h" represents the home directory of current user, which is specified by "user.home" system property
"%g" represents the generation number to distinguish rotated logs
"%u" represents a unique number to resolve conflicts
"%%" represents percent sign character '%'

Normally, the generation numbers are not larger than given file count and follow the sequence 0, 1, 2.... If the file count is larger than one, but the generation field("%g") has not been specified in the pattern, then the generation number after a dot will be added to the end of the file name,

The "%u" unique field is used to avoid conflicts and set to 0 at first. If one FileHandler tries to open the filename which is currently in use by another process, it will repeatedly increment the unique number field and try again. If the "%u" component has not been included in the file name pattern and some contention on a file does occur then a unique numerical value will be added to the end of the filename in question immediately to the right of a dot. The unique IDs for avoiding conflicts is only guaranteed to work reliably when using a local disk file system.

Summary

Public Constructors
	FileHandler() Construct a `FileHandler` using `LogManager` properties or their default value
	FileHandler(String pattern) Construct a `FileHandler`, the given name pattern is used as output filename, the file limit is set to zero(no limit), and the file count is set to one, other configuration using `LogManager` properties or their default value This handler write to only one file and no amount limit.
	FileHandler(String pattern, boolean append) Construct a `FileHandler`, the given name pattern is used as output filename, the file limit is set to zero(i.e.
	FileHandler(String pattern, int limit, int count) Construct a `FileHandler`, the given name pattern is used as output filename, the file limit is set to given limit argument, and the file count is set to given count argument, other configuration using `LogManager` properties or their default value This handler is configured to write to a rotating set of count files, when the limit of bytes has been written to one output file, another file will be opened instead.
	FileHandler(String pattern, int limit, int count, boolean append) Construct a `FileHandler`, the given name pattern is used as output filename, the file limit is set to given limit argument, the file count is set to given count argument, and the append mode is set to given append argument, other configuration using `LogManager` properties or their default value This handler is configured to write to a rotating set of count files, when the limit of bytes has been written to one output file, another file will be opened instead.

Public Methods
void	close() Flush and close all opened files.
void	publish(LogRecord record) Publish a `LogRecord`

[Expand]

Inherited Methods

From class java.util.logging.StreamHandler

From class java.util.logging.Handler

abstract void	close() Closes this handler.
abstract void	flush() Flushes any buffered output.
String	getEncoding() Gets the character encoding used by this handler.
ErrorManager	getErrorManager() Gets the error manager used by this handler to report errors during logging.
Filter	getFilter() Gets the filter used by this handler.
Formatter	getFormatter() Gets the formatter used by this handler to format the logging messages.
Level	getLevel() Gets the logging level of this handler.
boolean	isLoggable(LogRecord record) Determines whether the supplied log record need to be logged.
abstract void	publish(LogRecord record) Accepts an actual logging request.
void	reportError(String msg, Exception ex, int code) Report an error to the error manager associated with this handler.
void	setEncoding(String encoding) Sets the character encoding used by this handler.
void	setErrorManager(ErrorManager em) Sets the error manager for this handler.
void	setFilter(Filter newFilter) Sets the filter to be used by this handler.
void	setFormatter(Formatter newFormatter) Sets the formatter to be used by this handler.
void	setLevel(Level newLevel) Sets the logging level of this handler.

From class java.lang.Object

Object	clone() Returns a new instance of the same class as the receiver, whose slots have been filled in with the values in the slots of the receiver.
boolean	equals(Object o) Compares the argument to the receiver, and returns true if they represent the same object using a class specific comparison.
void	finalize() Called by the virtual machine when there are no longer any (non-weak) references to the receiver.
final Class<? extends Object>	getClass() Returns the unique instance of java.lang.Class which represents the class of the receiver.
int	hashCode() Returns an integer hash code for the receiver.
final void	notify() Causes one thread which is `wait` ing on the receiver to be made ready to run.
final void	notifyAll() Causes all threads which are `wait` ing on the receiver to be made ready to run.
String	toString() Returns a string containing a concise, human-readable description of the receiver.
final void	wait(long time, int frac) Causes the thread which sent this message to be made not ready to run either pending some change in the receiver (as indicated by `notify` or `notifyAll`) or the expiration of the timeout.
final void	wait(long time) Causes the thread which sent this message to be made not ready to run either pending some change in the receiver (as indicated by `notify` or `notifyAll`) or the expiration of the timeout.
final void	wait() Causes the thread which sent this message to be made not ready to run pending some change in the receiver (as indicated by `notify` or `notifyAll`).

Public Constructors

public FileHandler ()

Construct a FileHandler using LogManager properties or their default value

Throws

IOException	if any IO exception happened
SecurityException	if security manager exists and it determines that caller does not have the required permissions to control this handler, required permissions include `LogPermission("control")` and other permission like `FilePermission("write")`, etc.

public FileHandler (String pattern)

Construct a FileHandler, the given name pattern is used as output filename, the file limit is set to zero(no limit), and the file count is set to one, other configuration using LogManager properties or their default value This handler write to only one file and no amount limit.

Parameters

pattern	the name pattern of output file

Throws

IOException	if any IO exception happened
SecurityException	if security manager exists and it determines that caller does not have the required permissions to control this handler, required permissions include `LogPermission("control")` and other permission like `FilePermission("write")`, etc.
NullPointerException	if the pattern is `null`.
IllegalArgumentException	if the pattern is empty.

public FileHandler (String pattern, boolean append)

Construct a FileHandler, the given name pattern is used as output filename, the file limit is set to zero(i.e. no limit applies), the file count is initialized to one, and the value of append becomes the new instance's append mode. Other configuration is done using LogManager properties. This handler write to only one file and no amount limit.

Parameters

pattern	the name pattern of output file
append	the append mode

Throws

IOException	if any IO exception happened
SecurityException	if security manager exists and it determines that caller does not have the required permissions to control this handler, required permissions include `LogPermission("control")` and other permission like `FilePermission("write")`, etc.
NullPointerException	if the pattern is `null`.
IllegalArgumentException	if the pattern is empty.

public FileHandler (String pattern, int limit, int count)

Construct a FileHandler, the given name pattern is used as output filename, the file limit is set to given limit argument, and the file count is set to given count argument, other configuration using LogManager properties or their default value This handler is configured to write to a rotating set of count files, when the limit of bytes has been written to one output file, another file will be opened instead.

Parameters

pattern	the name pattern of output file
limit	the data amount limit in bytes of one output file, cannot less than one
count	the maximum number of files can be used, cannot less than one

Throws

IOException	if any IO exception happened
SecurityException	if security manager exists and it determines that caller does not have the required permissions to control this handler, required permissions include `LogPermission("control")` and other permission like `FilePermission("write")`, etc.
NullPointerException	if pattern is `null`.
IllegalArgumentException	if count<1, or limit<0

public FileHandler (String pattern, int limit, int count, boolean append)

Construct a FileHandler, the given name pattern is used as output filename, the file limit is set to given limit argument, the file count is set to given count argument, and the append mode is set to given append argument, other configuration using LogManager properties or their default value This handler is configured to write to a rotating set of count files, when the limit of bytes has been written to one output file, another file will be opened instead.

Parameters

pattern	the name pattern of output file
limit	the data amount limit in bytes of one output file, cannot less than one
count	the maximum number of files can be used, cannot less than one
append	the append mode

Throws

IOException	if any IO exception happened
SecurityException	if security manager exists and it determines that caller does not have the required permissions to control this handler, required permissions include `LogPermission("control")` and other permission like `FilePermission("write")`, etc.
NullPointerException	if pattern is `null`.
IllegalArgumentException	if count<1, or limit<0

Public Methods

public void close ()

Flush and close all opened files.

Throws

SecurityException	if security manager exists and it determines that caller does not have the required permissions to control this handler, required permissions include `LogPermission("control")` and other permission like `FilePermission("write")`, etc.

public void publish (LogRecord record)

Publish a LogRecord

Parameters

record	the log record to be published

Feb	MAR	Apr
	30
2008	2009	2010

Interfaces

Classes

FileHandler

Class Overview

Summary

Public Constructors

public FileHandler ()

Throws

public FileHandler (String pattern)

Parameters

Throws

public FileHandler (String pattern, boolean append)

Parameters

Throws

public FileHandler (String pattern, int limit, int count)

Parameters

Throws

public FileHandler (String pattern, int limit, int count, boolean append)

Parameters

Throws

Public Methods

public void close ()

Throws

public void publish (LogRecord record)

Parameters