If this property is absent, or if the Wrapper is unable to write at the specified location (e.g because of a permission issue),
then the messages will be logged to a default log file named "wrapper.log"
in the working directory.
Failing that, output to the log file will be disabled and logging will only continue in the console, syslog or EventLog.
Starting from version 3.5.30, the Wrapper has the ability to resume logging
into the log file when it becomes available again.
The following diagram represents the fall back and resume mechanisms:
Setting the property to a blank value will cause file logging to be disabled.
In versions 3.5.31 to 3.5.34, the Wrapper contains a bug which causes to use the default log file instead of disabling file logging when a blank value is specified.
A better practice to disable output to the log file, and which works with all versions of the Wrapper above 2.2.5,
is to set wrapper.logfile.loglevel to NONE.
Log File Name generated by Tokens:
The specified log file name may be able to contain one or both of the tokens;
ROLLNUM and YYYYMMDD.
The ROLLNUM token is used when the log file is rolled.
If the format is "wrapper.log.ROLLNUM",
the "ROLLNUM" token is replaced with an integer,
and then the roll numbers will be appended to the end of the file name "wrapper.log".
The larger roll number values, the older files.
The most recent rolled log file will always have a roll number of "1",
which is "wrapper.log.1".
The second recent one will be "wrapper.log.2".
property has a rolling mode,
if a ROLLNUM token is not included in the specified log file,
".ROLLNUM" will be appended at the end by default.
Whenever either token does not apply to a given file name format,
it will be stripped from the generated file name. When a token part is stripped,
the preceding character will also be stripped if it is a ".", "-", or "_".