Home Tutorials Log4j A simple example of log4j

Related Tutorials


 
 

Share on Google+Share on Google+

A simple example of log4j

Advertisement
This Example shows you how to create a log in a program.

A simple example of log4j

     

This Example shows you how to create a log in a program.

Description of the code:
  1. Logger.getLogger(): Logger class is used for handling the majority of log operations and getLogger method is used for return a logger according to the value of the parameter. If the logger already exists, then the existing instance will be returned. If the logger is not already exist, then create a new instance.
      
  2. Logger.debug(): This method is used to check that the specified category is DEBUG enabled or not, if yes then it converts the massage passed as a string argument to a string by using appropriate object renderer of class ObjectRenderer.
      
  3. Logger.info(): This method is used to check that the specified category is INFO enabled or not, if yes then it converts the massage passed as a string argument to a string by using appropriate object renderer of class ObjectRenderer.
      
  4. Logger.warn(): This method is used to check that the specified category is WARN enabled or not, if yes then it converts the massage passed as a string argument to a string by using appropriate object renderer of class ObjectRenderer.
      
  5. Logger.error(): This method is used to check that the specified category is ERROR enabled or not, if yes then it converts the massage passed as a string argument to a string by using appropriate object renderer of class ObjectRenderer.
      
  6. Logger.fatal(): This method is used to check that the specified category is FATAL enabled or not, if yes then it converts the massage passed as a string argument to a string by using appropriate object renderer of class ObjectRenderer.

LogExample.java


import org.apache.log4j.Logger;

public class LogExample {

  public LogExample() {
  }
  static Logger log = Logger.getLogger(LogExample.class);

  public static void main(String argsp[]) {

  log.debug("Here is some DEBUG");
  log.info("Here is some INFO");
  log.warn("Here is some WARN");
  log.error("Here is some ERROR");
  log.fatal("Here is some FATAL");
  }
}

log4j.properties


log4j.rootLogger=debug, stdout
log4j.appender.stdout=org.apache.log4j.ConsoleAppender
log4j.appender.stdout.Target=System.out
log4j.appender.stdout.layout=org.apache.log4j.PatternLayout
log4j.appender.stdout.layout.ConversionPattern=[%5p%d{mm:ss
(
%F:%M:%L)%n%m%n%n


Output:
[DEBUG55:17 (LogExample.java:main:11)
Here is some DEBUG

INFO55:17 (LogExample.java:main:12)
Here is some INFO

WARN55:17 (LogExample.java:main:13)
Here is some WARN

[ERROR55:17 (LogExample.java:main:14)
Here is some ERROR

[FATAL55:17 (LogExample.java:main:15)
Here is some FATAL

Download code

     

Advertisement

If you enjoyed this post then why not add us on Google+? Add us to your Circles



Liked it!  Share this Tutorial


Follow us on Twitter, or add us on Facebook or Google Plus to keep you updated with the recent trends of Java and other open source platforms.

Posted on: September 10, 2008

Related Tutorials

Discuss: A simple example of log4j  

Post your Comment


Your Name (*) :
Your Email :
Subject (*):
Your Comment (*):
  Reload Image
 
 
Comments:1
ME@1970
June 17, 2011
Thank you

This is just the simple example I was looking for. I placed the log4j.properties in the root source folder of Eclipse and this example ran fine! Thanks.
DMCA.com