Class DailyRollingFileAppender
- All Implemented Interfaces:
Appender
,OptionHandler
FileAppender
so that the
underlying file is rolled over at a user chosen frequency.
DailyRollingFileAppender has been observed to exhibit
synchronization issues and data loss. The log4j extras
companion includes alternatives which should be considered
for new deployments and which are discussed in the documentation
for org.apache.log4j.rolling.RollingFileAppender.
The rolling schedule is specified by the DatePattern
option. This pattern should follow the SimpleDateFormat
conventions. In particular, you must escape literal text
within a pair of single quotes. A formatted version of the date
pattern is used as the suffix for the rolled file name.
For example, if the File option is set to
/foo/bar.log
and the DatePattern set to
'.'yyyy-MM-dd
, on 2001-02-16 at midnight, the logging
file /foo/bar.log
will be copied to
/foo/bar.log.2001-02-16
and logging for 2001-02-17
will continue in /foo/bar.log
until it rolls over
the next day.
Is is possible to specify monthly, weekly, half-daily, daily, hourly, or minutely rollover schedules.
DatePattern | Rollover schedule | Example |
---|---|---|
'.'yyyy-MM
| Rollover at the beginning of each month | At midnight of May 31st, 2002 /foo/bar.log will be
copied to /foo/bar.log.2002-05 . Logging for the month
of June will be output to /foo/bar.log until it is
also rolled over the next month.
|
'.'yyyy-ww
| Rollover at the first day of each week. The first day of the week depends on the locale. | Assuming the first day of the week is Sunday, on Saturday
midnight, June 9th 2002, the file /foo/bar.log will be
copied to /foo/bar.log.2002-23. Logging for the 24th week
of 2002 will be output to /foo/bar.log until it is
rolled over the next week.
|
'.'yyyy-MM-dd
| Rollover at midnight each day. | At midnight, on March 8th, 2002, /foo/bar.log will
be copied to /foo/bar.log.2002-03-08 . Logging for the
9th day of March will be output to /foo/bar.log until
it is rolled over the next day.
|
'.'yyyy-MM-dd-a
| Rollover at midnight and midday of each day. | At noon, on March 9th, 2002, /foo/bar.log will be
copied to /foo/bar.log.2002-03-09-AM . Logging for the
afternoon of the 9th will be output to /foo/bar.log
until it is rolled over at midnight.
|
'.'yyyy-MM-dd-HH
| Rollover at the top of every hour. | At approximately 11:00.000 o'clock on March 9th, 2002,
/foo/bar.log will be copied to
/foo/bar.log.2002-03-09-10 . Logging for the 11th hour
of the 9th of March will be output to /foo/bar.log
until it is rolled over at the beginning of the next hour.
|
'.'yyyy-MM-dd-HH-mm
| Rollover at the beginning of every minute. | At approximately 11:23,000, on March 9th, 2001,
/foo/bar.log will be copied to
/foo/bar.log.2001-03-09-10-22 . Logging for the minute
of 11:23 (9th of March) will be output to
/foo/bar.log until it is rolled over the next minute.
|
Do not use the colon ":" character in anywhere in the DatePattern option. The text before the colon is interpeted as the protocol specificaion of a URL which is probably not what you want.
- Author:
- Eirik Lygre, Ceki Gülcü
-
Field Summary
Fields inherited from class org.apache.log4j.FileAppender
bufferedIO, bufferSize, fileAppend, fileName
Fields inherited from class org.apache.log4j.WriterAppender
encoding, immediateFlush, qw
Fields inherited from class org.apache.log4j.AppenderSkeleton
closed, errorHandler, headFilter, layout, name, tailFilter, threshold
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Constructor Summary
ConstructorsConstructorDescriptionThe default constructor does nothing.DailyRollingFileAppender
(Layout layout, String filename, String datePattern) Instantiate aDailyRollingFileAppender
and open the file designated byfilename
. -
Method Summary
Modifier and TypeMethodDescriptionvoid
If the value of File is notnull
, thenFileAppender.setFile(java.lang.String)
is called with the values of File and Append properties.Returns the value of the DatePattern option.void
setDatePattern
(String pattern) The DatePattern takes a string in the same format as expected bySimpleDateFormat
.protected void
subAppend
(LoggingEvent event) This method differentiates DailyRollingFileAppender from its super class.Methods inherited from class org.apache.log4j.FileAppender
closeFile, getAppend, getBufferedIO, getBufferSize, getFile, reset, setAppend, setBufferedIO, setBufferSize, setFile, setFile, setQWForFiles
Methods inherited from class org.apache.log4j.WriterAppender
append, checkEntryConditions, close, closeWriter, createWriter, getEncoding, getImmediateFlush, requiresLayout, setEncoding, setErrorHandler, setImmediateFlush, setWriter, shouldFlush, writeFooter, writeHeader
Methods inherited from class org.apache.log4j.AppenderSkeleton
addFilter, clearFilters, doAppend, finalize, getErrorHandler, getFilter, getFirstFilter, getLayout, getName, getThreshold, isAsSevereAsThreshold, setLayout, setName, setThreshold
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Constructor Details
-
DailyRollingFileAppender
public DailyRollingFileAppender()The default constructor does nothing. -
DailyRollingFileAppender
public DailyRollingFileAppender(Layout layout, String filename, String datePattern) throws IOException Instantiate aDailyRollingFileAppender
and open the file designated byfilename
. The opened filename will become the ouput destination for this appender.- Throws:
IOException
-
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Method Details
-
setDatePattern
The DatePattern takes a string in the same format as expected bySimpleDateFormat
. This options determines the rollover schedule. -
getDatePattern
Returns the value of the DatePattern option. -
activateOptions
public void activateOptions()Description copied from class:FileAppender
If the value of File is notnull
, thenFileAppender.setFile(java.lang.String)
is called with the values of File and Append properties.- Specified by:
activateOptions
in interfaceOptionHandler
- Overrides:
activateOptions
in classFileAppender
-
subAppend
This method differentiates DailyRollingFileAppender from its super class.Before actually logging, this method will check whether it is time to do a rollover. If it is, it will schedule the next rollover time and then rollover.
- Overrides:
subAppend
in classWriterAppender
-