Dynamic java logging properties file

Question

Hello,
I am looking for a dynamic way to set a property in a java logging properties file.
For example something like this:
java.util.logging.FileHandler.pattern = ${log.dir}/logfile%u.log
..where log.dir is a system property. But this does not work. Any other way to do it?
Thanks in advance,
Rohnny

Answer 1

This pattern doesn't work ? here is the content of my
logging.properties file.
java.util.logging.FileHandler.pattern = LOGFILE.log
java.util.logging.FileHandler.limit = 50000
java.util.logging.FileHandler.count = 1
java.util.logging.FileHandler.formatter =
java.util.logging.SimpleFormatter
FIRST_LOGGER.Handler = java.util.logging.FileHandler
FIRST_LOGGER.level = ALL
SECOND_LOGGER.Handler =
java.util.logging.FileHandler
SECOND_LOGGER.level = ALLIt seems like you're not thoroughly reading the spec on this stuff.
I don't think ".Handler" is even a valid property on a logger.
Loggers aren't typically initialized with a complex configuration out of a configuration file...unless you write your own custom format. For instance, FileHandler is a class, so when you define java.util.logging.FileHandler.pattern in the config file, you're defining it for every default instance of FileHandler...so naturally both your loggers that use FileHandlers will write to the same file.
I've never done this before, but here's what I came up with after reading the spec:
1) define 1 subclass of FileHandler for each file you want to write to... let's call them FileHandlerA and FileHandlerB. All they have to do is extend FileHandler, nothing else.
2) define the patterns for each subclass in the config file. You can also define any other properties you want for each handler, such as .level, .limit, .count, etc.
mypackage.myhandlers.FileHandlerA.pattern = LogFile-A.log
mypackage.myhandlers.FileHandlerB.pattern = LogFile-B.log
// ... more config here
3) define the loggers in the config file and specify the handlers to use on each:
FIRST_LOGGER.handlers = mypackage.myhandlers.FileHandlerA
SECOND_LOGGER.handlers = mypackage.myhandlers.FileHandlerB
4) create your Loggers in your code:
Logger firstLog = Logger.getLogger("FIRST_LOGGER");
Logger secondLog = Logger.getLogger("SECOND_LOGGER");
Good luck.