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Posted to log4j-user@logging.apache.org by Modha Kumar <mk...@sentius.com> on 2002/02/15 20:36:18 UTC
Newbie Questions....
Hi All
I just dowloaded Log4j and started working on some samples, I have these questions.
1. There are 2 jars in distribution Log4j.jar and Log4j-core.jar do we need both of these. What is the necessity for 2 jars ?
2. I downloaded Log4j version 1.1.3 eventhough documentation says that there is a Logger class org.apache.log4j.Logger
I did not find one in either of jars. There is a Category class which I was able to use. What version of jar has Logger ?
3. Documentation says
" Log4j makes it easy to name loggers by software component. This can be accomplished by statically
instantiating a logger in each class, with the logger name equal to the fully qualified name of the class. "
should I put
static Category logger = Category.getInstance(MyClass.class.getName());
at the top of every class and have configuration read like this in say constructor
PropertyConfigurator.configure("d:/dev-web/src/log4j.conf");
Then it will log to all appenders in log4j.conf
Documentation : " it is possible to configure a logger and then to retrieve the same instance somewhere else in the code without passing around references"
does it mean this logger is available in same class , .... I am clueless on usage
"Can anybody comment why one should require so many loggers one for each class"
I can understand if one module logs to a particular file, why is this logger at class level.
4.I tried to use sort1.lcf which I got from samples
log4j.rootCategory=, A1
log4j.appender.A1=org.apache.log4j.ConsoleAppender
log4j.appender.A1.layout=org.apache.log4j.PatternLayout
log4j.appender.A1.layout.ConversionPattern=%-4r %-5p [%t] %37c %3x - %m%n
put this line at top
static Category logger = Category.getInstance(HTTPToXML.class.getName());
I have just one class in my package which extends extends org.xml.sax.helpers.DefaultHandler i put 2 debug statements
logger.debug("Entering application.");
logger.debug("Exiting application.");
I get this as output...
0 DEBUG [main] com.sentius.webhandler.HTTPToXML - Entering application.
63 DEBUG [main] com.sentius.webhandler.HTTPToXML - Exiting application.
78 DEBUG [main] com.sentius.webhandler.HTTPToXML - Entering application.
78 DEBUG [main] com.sentius.webhandler.HTTPToXML - Exiting application.
I read about appender additivity since there is just one class in my package I dont know where the duplicates are comming from.
Intrestingly output looks like my method ran twice but this is just a main method calling init() method a normal java standalone
app.
Any comments....
Replies will be greatly appreciated.
Thanks
Modha/-
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Re: Newbie Questions....
Posted by bryan hansen <bh...@yahoo.com>.
Well, I was going to say that you could go to this
link:
http://www.vipan.com/htdocs/log4jhelp.html
but it appears to be down right now...I hope they get
it back up because it was really useful. Loggers are
part of the 1.2 release, so for 1.1.3 you should use
Categories...
HTH
Bryan
--- Modha Kumar <mk...@sentius.com> wrote:
> Hi All
> I just dowloaded Log4j and started working on some
> samples, I have these questions.
>
> 1. There are 2 jars in distribution Log4j.jar and
> Log4j-core.jar do we need both of these. What is the
> necessity for 2 jars ?
>
> 2. I downloaded Log4j version 1.1.3 eventhough
> documentation says that there is a Logger class
> org.apache.log4j.Logger
> I did not find one in either of jars. There is a
> Category class which I was able to use. What version
> of jar has Logger ?
>
> 3. Documentation says
> " Log4j makes it easy to name loggers by software
> component. This can be accomplished by statically
> instantiating a logger in each class, with the
> logger name equal to the fully qualified name of the
> class. "
>
> should I put
> static Category logger =
> Category.getInstance(MyClass.class.getName());
> at the top of every class and have configuration
> read like this in say constructor
>
>
PropertyConfigurator.configure("d:/dev-web/src/log4j.conf");
> Then it will log to all appenders in log4j.conf
>
> Documentation : " it is possible to configure a
> logger and then to retrieve the same instance
> somewhere else in the code without passing around
> references"
>
> does it mean this logger is available in same class
> , .... I am clueless on usage
>
> "Can anybody comment why one should require so many
> loggers one for each class"
> I can understand if one module logs to a particular
> file, why is this logger at class level.
>
> 4.I tried to use sort1.lcf which I got from samples
>
> log4j.rootCategory=, A1
> log4j.appender.A1=org.apache.log4j.ConsoleAppender
>
log4j.appender.A1.layout=org.apache.log4j.PatternLayout
> log4j.appender.A1.layout.ConversionPattern=%-4r %-5p
> [%t] %37c %3x - %m%n
>
> put this line at top
> static Category logger =
> Category.getInstance(HTTPToXML.class.getName());
>
> I have just one class in my package which extends
> extends org.xml.sax.helpers.DefaultHandler i put 2
> debug statements
> logger.debug("Entering application.");
> logger.debug("Exiting application.");
>
> I get this as output...
> 0 DEBUG [main]
> com.sentius.webhandler.HTTPToXML - Entering
> application.
> 63 DEBUG [main]
> com.sentius.webhandler.HTTPToXML - Exiting
> application.
> 78 DEBUG [main]
> com.sentius.webhandler.HTTPToXML - Entering
> application.
> 78 DEBUG [main]
> com.sentius.webhandler.HTTPToXML - Exiting
> application.
>
> I read about appender additivity since there is just
> one class in my package I dont know where the
> duplicates are comming from.
> Intrestingly output looks like my method ran twice
> but this is just a main method calling init() method
> a normal java standalone
> app.
> Any comments....
>
> Replies will be greatly appreciated.
>
> Thanks
> Modha/-
>
>
>
>
> --
> To unsubscribe, e-mail:
> <ma...@jakarta.apache.org>
> For additional commands, e-mail:
> <ma...@jakarta.apache.org>
>
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