TimeBasedRollingPolicy Class Reference

Inherits RollingPolicyBase, and TriggeringPolicy.

List of all members.


Detailed Description

TimeBasedRollingPolicy is both easy to configure and quite powerful.

In order to use TimeBasedRollingPolicy, the FileNamePattern option must be set. It basically specifies the name of the rolled log files. The value FileNamePattern should consist of the name of the file, plus a suitably placed d conversion specifier. The d conversion specifier may contain a date and time pattern as specified by the log4cxx::helpers::SimpleDateFormat class. If the date and time pattern is ommitted, then the default pattern of "yyyy-MM-dd" is assumed. The following examples should clarify the point.

FileNamePattern value Rollover schedule Example
/wombat/folder/foo.d Daily rollover (at midnight). Due to the omission of the optional time and date pattern for the d token specifier, the default pattern of "yyyy-MM-dd" is assumed, which corresponds to daily rollover. During November 23rd, 2004, logging output will go to the file /wombat/foo.2004-11-23. At midnight and for the rest of the 24th, logging output will be directed to /wombat/foo.2004-11-24.
/wombat/foo.d{yyyy-MM}.log Rollover at the beginning of each month. During the month of October 2004, logging output will go to /wombat/foo.2004-10.log. After midnight of October 31st and for the rest of November, logging output will be directed to /wombat/foo.2004-11.log.

Automatic file compression

TimeBasedRollingPolicy supports automatic file compression. This feature is enabled if the value of the FileNamePattern option ends with .gz or .zip.

FileNamePattern value Rollover schedule Example
/wombat/foo.d.gz Daily rollover (at midnight) with automatic GZIP compression of the arcived files. During November 23rd, 2004, logging output will go to the file /wombat/foo.2004-11-23. However, at midnight that file will be compressed to become /wombat/foo.2004-11-23.gz. For the 24th of November, logging output will be directed to /wombat/folder/foo.2004-11-24 until its rolled over at the beginning of the next day.

Decoupling the location of the active log file and the archived log files

The active file is defined as the log file for the current period whereas archived files are thos files which have been rolled over in previous periods.

By setting the ActiveFileName option you can decouple the location of the active log file and the location of the archived log files.

FileNamePattern value ActiveFileName Rollover schedule Example
/wombat/foo.log.d /wombat/foo.log Daily rollover.

During November 23rd, 2004, logging output will go to the file /wombat/foo.log. However, at midnight that file will archived as /wombat/foo.log.2004-11-23. For the 24th of November, logging output will be directed to /wombat/folder/foo.log until its archived as /wombat/foo.log.2004-11-24 at the beginning of the next day.

If configuring programatically, do not forget to call activateOptions method before using this policy. Moreover, activateOptions of TimeBasedRollingPolicy must be called before calling the activateOptions method of the owning RollingFileAppender.


Public Member Functions

 TimeBasedRollingPolicy ()
void addRef () const
void releaseRef () const
void activateOptions (log4cxx::helpers::Pool &)
 Activate the options that were previously set with calls to option setters.
RolloverDescriptionPtr initialize (const LogString &file, const bool append, log4cxx::helpers::Pool &pool)
 Initialize the policy and return any initial actions for rolling file appender.
RolloverDescriptionPtr rollover (const LogString &activeFile, log4cxx::helpers::Pool &pool)
 Prepare for a rollover.
virtual bool isTriggeringEvent (Appender *appender, const log4cxx::spi::LoggingEventPtr &event, const LogString &filename, size_t fileLength)
 Determines if a rollover may be appropriate at this time.

Protected Member Functions

log4cxx::pattern::PatternMap getFormatSpecifiers () const


Constructor & Destructor Documentation

TimeBasedRollingPolicy  ) 
 


Member Function Documentation

void activateOptions log4cxx::helpers::Pool  )  [virtual]
 

Activate the options that were previously set with calls to option setters.

This allows to defer activiation of the options until all options have been set. This is required for components which have related options that remain ambigous until all are set.

For example, the FileAppender has the File and Append options both of which are ambigous until the other is also set.

Implements RollingPolicyBase.

void addRef  )  const [virtual]
 

Reimplemented from RollingPolicyBase.

log4cxx::pattern::PatternMap getFormatSpecifiers  )  const [protected, virtual]
 

Implements RollingPolicyBase.

RolloverDescriptionPtr initialize const LogString file,
const bool  append,
log4cxx::helpers::Pool pool
[virtual]
 

Initialize the policy and return any initial actions for rolling file appender.

Parameters:
file current value of RollingFileAppender.getFile().
append current value of RollingFileAppender.getAppend().
pool pool for any required allocations.
Returns:
Description of the initialization, may be null to indicate no initialization needed.
Exceptions:
SecurityException if denied access to log files.

Implements RollingPolicy.

virtual bool isTriggeringEvent Appender appender,
const log4cxx::spi::LoggingEventPtr event,
const LogString filename,
size_t  fileLength
[virtual]
 

Determines if a rollover may be appropriate at this time.

If true is returned, RolloverPolicy.rollover will be called but it can determine that a rollover is not warranted.

Parameters:
appender A reference to the appender.
event A reference to the currently event.
filename The filename for the currently active log file.
fileLength Length of the file in bytes.
Returns:
true if a rollover should occur.

Implements TriggeringPolicy.

void releaseRef  )  const [virtual]
 

Reimplemented from RollingPolicyBase.

RolloverDescriptionPtr rollover const LogString activeFile,
log4cxx::helpers::Pool pool
[virtual]
 

Prepare for a rollover.

This method is called prior to closing the active log file, performs any necessary preliminary actions and describes actions needed after close of current log file.

Parameters:
activeFile file name for current active log file.
pool pool for any required allocations.
Returns:
Description of pending rollover, may be null to indicate no rollover at this time.
Exceptions:
SecurityException if denied access to log files.

Implements RollingPolicy.


The documentation for this class was generated from the following file: