Using Multiple Loggers for SimpleFormatter AND XML

[nico]

I posted this over at javaranch but didn't get a reply. It concerns
Logging XML and simple formats:

It seems that if I create two Logger objects, one using
SimpleFormatting for the FileHandler, and the other using
XMLFormatting for the FileHandler, and try to write to the same file
(with appending set to true) it creates two separate files:

logtest.log (Simple formatting)
logtest.log.1 (xml formatting)

However, it seems that the .log and .log.1 are always in the order of
the Logger that I use (so if I put the xml first and the simple
formatting second it will be .log for xml and .log.1 for simple). I'm
thinking that it's probably a good idea to just have the simple
default to .log and xml to .xml. Is it even possible to use both
simple and xml formmated logging on the same file?

I'm planning on letting the end-user have the option to set log style
as a context init paramater and suppose I'd like to also allow them to
provide the path/name as well. I could let them give a name and then
manually append .xml or .log based on the log style but that would be
ugly! ie mylog.log would get turned into mylog.log.xml!

My system: uname -a
Linux toshiba 2.6.22-14-generic i686 GNU/Linux

Here's the code I used to test this:

code:


import java.io.*;
import java.util.logging.*;

public class LogTest {
public static void main(String[] args) {

/* Log using Simple Formatting */
Logger log = Logger.getLogger("LogTester");
try{
FileHandler fileHandler = new FileHandler("logtest.log",
true);
fileHandler.setFormatter(new SimpleFormatter());
log.addHandler(fileHandler);
log.info("This is an info message logged simple");
log.warning("This is warning message logged simple");
}
catch (IOException e){}

/*Log using XML formmatting */
Logger log2 = Logger.getLogger("LogTester");
try{
FileHandler xmlHandler= new FileHandler("logtest.log",true);
xmlHandler.setFormatter(new XMLFormatter());
log2.addHandler(xmlHandler);
log2.info("This is info message logged as xml");
log2.warning("This is warning message logged as xml");
}
catch (IOException e){}
}
}

 

[Arne Vajhøj]

I posted this over at javaranch but didn't get a reply. It concerns
Logging XML and simple formats:

It seems that if I create two Logger objects, one using
SimpleFormatting for the FileHandler, and the other using
XMLFormatting for the FileHandler, and try to write to the same file
(with appending set to true) it creates two separate files:

logtest.log (Simple formatting)
logtest.log.1 (xml formatting)

However, it seems that the .log and .log.1 are always in the order of
the Logger that I use (so if I put the xml first and the simple
formatting second it will be .log for xml and .log.1 for simple). I'm
thinking that it's probably a good idea to just have the simple
default to .log and xml to .xml. Is it even possible to use both
simple and xml formmated logging on the same file?

I'm planning on letting the end-user have the option to set log style
as a context init paramater and suppose I'd like to also allow them to
provide the path/name as well. I could let them give a name and then
manually append .xml or .log based on the log style but that would be
ugly! ie mylog.log would get turned into mylog.log.xml!

It makes a lot of sense to me that log4j does not allow you to
mix simple formatting and XML formatting in the same file.

The result would be almost impossible to parse.

I can not see why appending the approriate file extension
should be bad. And it should ofcourse just be mylog.xml.

But something else. I don't know your app and your users. But
in many situations the system administrators would prefer
instead of specifying simple or xml in web.xml and doing
programatically configuration that the log4j configuration
was an external file where they could specify formatter,
filename, rotating and all that stuff.

Arne

 

[nico]

It makes a lot of sense to me that log4j does not allow you to
mix simple formatting and XML formatting in the same file.

The result would be almost impossible to parse.

I can not see why appending the approriate file extension
should be bad. And it should ofcourse just be mylog.xml.

But something else. I don't know your app and your users. But
in many situations the system administrators would prefer
instead of specifying simple or xml in web.xml and doing
programatically configuration that the log4j configuration
was an external file where they could specify formatter,
filename, rotating and all that stuff.

Arne

Thanks for your reply Arne. I'm actually not using log4j, I'm using
the java.util.logging package that's included in the jdk since 1.4
(although I appreciate that log4j was first and may have better
features to some).

 

[Arne Vajhøj]

Thanks for your reply Arne. I'm actually not using log4j, I'm using
the java.util.logging package that's included in the jdk since 1.4
(although I appreciate that log4j was first and may have better
features to some).

My mistake.

But I don't think it change much for my main points.

Arne