Tools

What Is Log4j, Why Log4j Came Into Picture

For logging log4j is the best even today, let us see little history behind this 

While developing Java/J2EE applications, for debugging an application that is to know the status of a java application at its execution time, in general we use system.out.println statements in the application right…

But we have some disadvantages while using SOPL (system.out.println) statements.

• Generally SOPL statements are printed on console, so there are temporary messages and when ever the console is closed then automatically the messages are removed from the console
• It is not possible to store the SOPL messages in a permanent place and these are singlethreaded model, means these will prints only one by one message on the console screen
• In order to overcome the problems  of  SOPL statements Log4j came into picture, with Log4j we can store the flow details of  our Java/J2EE in a file or databases
• This is a Open Source tool given by Apache, for only java projects, to record or write the status of an application at various places
• Working with log4j is nothing but working with classes & interfaces given in org.apache.log4j.*
• Log4j is a common tool, used for small to large scale Java/J2EE projects
• In Log4j we use log statements rather SOPL statements in the code to know the status of a project while it is executing
• In real time, after a project is released and it is installed in a client location then we call the location as on-site right, when executing the program at on-site location, if we got any problems occurred then these problems must report to the off showered engineers,  in this time we used to mail these Log files only so that they can check the problems easily