Log::Log4perl::DateFormat is a low-level helper class for the
advanced date formatting functions in Log::Log4perl::Layout::PatternLayout.
Unless youre writing your own Layout class like
Log::Log4perl::Layout::PatternLayout, theres probably not much use
for you to read this.
Log::Log4perl::DateFormat is a formatter which allows dates to be
formatted according to the log4j spec on
which allows the following placeholders to be recognized and processed:
Symbol Meaning Presentation Example
------ ------- ------------ -------
G era designator (Text) AD
e epoch seconds (Number) 1315011604
y year (Number) 1996
M month in year (Text & Number) July & 07
d day in month (Number) 10
h hour in am/pm (1~12) (Number) 12
H hour in day (0~23) (Number) 0
m minute in hour (Number) 30
s second in minute (Number) 55
S millisecond (Number) 978
E day in week (Text) Tuesday
D day in year (Number) 189
F day of week in month (Number) 2 (2nd Wed in July)
w week in year (Number) 27
W week in month (Number) 2
a am/pm marker (Text) PM
k hour in day (1~24) (Number) 24
K hour in am/pm (0~11) (Number) 0
z time zone (Text) Pacific Standard Time
Z RFC 822 time zone (Text) -0800
escape for text (Delimiter)
single quote (Literal)
For example, if you want to format the current Unix time in
"MM/dd HH:mm" format, all you have to do is this:
my $format = Log::Log4perl::DateFormat->new("MM/dd HH:mm");
my $time = time();
print $format->format($time), "\n";
While the new() method is expensive, because it parses the format
strings and sets up all kinds of structures behind the scenes,
followup calls to format() are fast, because DateFormat will
just call localtime() and sprintf() once to return the formatted
So, typically, you would initialize the formatter once and then reuse
it over and over again to display all kinds of time values.
Also, for your convenience,
the following predefined formats are available, just as outlined in the
Format Equivalent Example
ABSOLUTE "HH:mm:ss,SSS" "15:49:37,459"
DATE "dd MMM yyyy HH:mm:ss,SSS" "06 Nov 1994 15:49:37,459"
ISO8601 "yyyy-MM-dd HH:mm:ss,SSS" "1999-11-27 15:49:37,459"
APACHE "[EEE MMM dd HH:mm:ss yyyy]" "[Wed Mar 16 15:49:37 2005]"
So, instead of passing
you could just as well say
and get the same result later on.
Please contribute patches to the project on Github:
Send bug reports or requests for enhancements to the authors via our
MAILING LIST (questions, bug reports, suggestions/patches):
Authors (please contact them via the list above, not directly):
Mike Schilli <firstname.lastname@example.org>,
Kevin Goess <email@example.com>
Contributors (in alphabetical order):
Ateeq Altaf, Cory Bennett, Jens Berthold, Jeremy Bopp, Hutton
Davidson, Chris R. Donnelly, Matisse Enzer, Hugh Esco, Anthony
Foiani, James FitzGibbon, Carl Franks, Dennis Gregorovic, Andy
Grundman, Paul Harrington, Alexander Hartmaier David Hull,
Robert Jacobson, Jason Kohles, Jeff Macdonald, Markus Peter,
Brett Rann, Peter Rabbitson, Erik Selberg, Aaron Straup Cope,
Lars Thegler, David Viner, Mac Yang.