Log4E:FAQ
Table of contents |
Frequently Asked Questions
[1] How to do the initial setup of my logging framework
If you are already familiar with your logging framework you might want to skip this section.
This chapter gives you a slight idea how to make the initial setup of your logger. This
is NOT supported by Log4E at the moment and was not the intended use at the beginning of
this project.
Log4E does not ship any logging framework which means that you have to download and install it for yourself!
Examples are available for Log4j, Commons Logging, JDK 1.4 Logging (again: you have to do this for yourself).
Log4j
-
1. Download Log4j at http://logging.apache.org/
and copy the log4j.jar to your lib directory.
2. Create a new file 'log4j.properties' or 'log4j.xml' (case sensitive) and put it in your classpath. To be more concrete: Put in your source directory, the file will be copied by Eclipse automatically to your build directory.
For example:
.../MyEclipseProject/ .../MyEclipseProject/src/log4j.properties .../MyEclipseProject/src/com/mycompany/myapp/...
2a. Alternatively, you can use the method org.apache.log4j.PropertyConfigurator.configure("..../log4j.properties");
3. Edit the 'log4j.properties' to declare your own categories, log levels and appenders
(which means the output like standard out or a log file).
log4j.properties example:
####################################################################### # Categories and levels ####################################################################### log4j.rootCategory=ERROR, FileApp, ConApp log4j.category.de.jayefem=DEBUG ####################################################################### # Appenders ####################################################################### # ConApp is set to be a ConsoleAppender. log4j.appender.ConApp=org.apache.log4j.ConsoleAppender # ConApp uses PatternLayout. log4j.appender.ConApp.layout=org.apache.log4j.PatternLayout # Define Pattern log4j.appender.ConApp.layout.ConversionPattern=%d [%t] %-5p %c - %m%n # FileApp log4j.appender.FileApp=org.apache.log4j.RollingFileAppender log4j.appender.FileApp.File=D:/proj/Devel/Java/de.jayefem.log4e/log/log4e.log log4j.appender.FileApp.MaxFileSize=500KB # Keep one backup file log4j.appender.FileApp.MaxBackupIndex=1 log4j.appender.FileApp.layout=org.apache.log4j.PatternLayout log4j.appender.FileApp.layout.ConversionPattern=%d [%t] %-5p %c - %m%n
"de.jayefem", "ConApp", "FileApp" and the path to the logfile are selfdefined.
All other words are keywords of Log4j.
4. That's all. Have fun.
Note that there are much more possibilities to configure Log4j. Check http://logging.apache.org/ for more.
Jakarta Commons Logging
Jakarta Commons Logging Framework is a wrapper for all common logging frameworks.
If you want to use it, you have to install it AND the underlying logging framework.
To install the Commons Logging download it from http://jakarta.apache.org/commons/logging/
and put the commons-logging.jar in your lib directory.
The Commons Logging Frameworks uses Log4j by default. When Log4j isn't found in classpath
and JDK 1.4 or higher is being used, the JDK 1.4 logger will be used. If none of the
above applies, Commons Logging will fall back to the internal SimpleLog.
It is also possible to specify the logging framework directly:
1. Create a new file 'commons-logging.properties' and put it in your
classpath. To be more concrete: Put it in your source directory, the
file will be copied by Eclipse automatically to your build directory.
For example:
.../MyEclipseProject/ .../MyEclipseProject/src/commons-logging.properties .../MyEclipseProject/src/com/mycompany/myapp/...2. Edit the 'commons-logging.properties'.
commons-logging.properties example:
# #org.apache.commons.logging.LogFactory=org.apache.commons.logging.impl.LogFactoryImpl # SimpleLog #org.apache.commons.logging.Log = org.apache.commons.logging.impl.SimpleLog # JDK 1.4 logger #org.apache.commons.logging.Log=org.apache.commons.logging.impl.Jdk14Logger # Avalon Toolkit #org.apache.commons.logging.Log=org.apache.commons.logging.impl.LogKitLogger # Log4j org.apache.commons.logging.Log=org.apache.commons.logging.impl.Log4JLogger
As though it is not recommended to use Simplelog because it is not threadsafe, here's an example how to set it up:
1. Create a new file 'simplelog.properties' and put it in your
classpath. To be more concrete: Put it in your source directory, the
file will be copied by Eclipse automatically to your build directory.
For example:
.../MyEclipseProject/ .../MyEclipseProject/src/simplelog.properties .../MyEclipseProject/src/com/mycompany/myapp/...2. Edit the 'simplelog.properties' to declare your own categories and log levels.
simplelog.properties example:
# Default logging detail level for all instances of SimpleLog. Must be one of # ("trace", "debug", "info", "warn", "error", or "fatal"). If not specified, # defaults to "info". org.apache.commons.logging.simplelog.defaultlog=warn # Logging detail level for a SimpleLog instance named "xxxxx". Must be one of # ("trace", "debug", "info", "warn", "error", or "fatal"). If not specified, the # default logging detail level is used. org.apache.commons.logging.simplelog.log.de.jayefem.log4e=debug # Set to true if you want the Log instance name to be included in output # messages. Defaults to false. org.apache.commons.logging.simplelog.showlogname=false # Set to true if you want the last componet of the name to be included in # output messages. Defaults to true. org.apache.commons.logging.simplelog.showShortLogname=true # Set to true if you want the current date and time to be included in output # messages. Default is false. org.apache.commons.logging.simplelog.showdatetime=true
See http://jakarta.apache.org/commons/logging/ for more.
JDK 1.4 Logging
-
1. Use JDK 1.4 or higher :-)
2. Create a new file 'logging.properties'.
3. Invoke your application with:
java -Djava.util.logging.config.file=D:\your\path\to\logging.properties com.mycompany.myproject.MyClass
logging.properties example:
# handlers handlers=java.util.logging.FileHandler, java.util.logging.ConsoleHandler # general level .level=INFO # file handler java.util.logging.FileHandler.pattern = %h/java%u.log java.util.logging.FileHandler.limit = 50000 java.util.logging.FileHandler.count = 1 java.util.logging.FileHandler.formatter = java.util.logging.XMLFormatter # console handler java.util.logging.ConsoleHandler.level = FINEST java.util.logging.ConsoleHandler.formatter = java.util.logging.SimpleFormatter test.de.jayefem.log4e.logkits.JDK1_4_Logging.level = FINEST
Since I am not an expert of JDK 1.4 logging there might be better ways to configure the
logging framework. Suggestions are welcome.
See http://java.sun.com/j2se/1.4.2/docs/api/java/util/logging/package-summary.html for more information.
[2] How to start Eclipse with JDK 1.5?
Start it with paramter '-vm'. E.g. on Windows: eclipse.exe -vm C:\j2re1.5.0_01\bin\javaw.exe
[3] How to export/import the Log4E configuration?
the template definitions are saved in:
<path_to>\workspace\.metadata\.plugins\de.jayefem.log4e\log4e-profiles.xml
the preferences are saved in:
<path_to>\workspace\.metadata\.plugins\org.eclipse.core.runtime\.settings\de.jayefem.log4e.prefs
<path_to> is the path where your workspace is stored. See "File->Switch Workspace..." to find out where your current workspace is.
Import:
- Shut down Eclipse
- Check if "log4e-profiles.xml" already exists. If so, you have to merge the exported file with the existing file for yourself.
- Copy "log4e-profiles.xml" and "de.jayefem.log4e.prefs" to the appropiate workspace folders