Question

I am trying to learn the trick on how to run the code which prints a lot of stuff when the debug flag is on.

How is that done in java.

A very naive way I can think of is have the debug flag in all the methods i write

and write something like

 if (this.debug == true){
 System.out.println("blah blah");
  }

But there should be much more elegant way rather than having all these ifs in code?

Also, is there a way I can get the line number of certain execution in code:

For example if there is an exception

            try:

/* line number 22 */

 catch Exception e{
         //print that exception occured in above line number??
    }

Probably very lame questions.
THanks

Answer 1

Use logging framework that will do it for you – for example : log4j, slf4j

For example:

log.debug("some text");

now in logging configuration properties file choose to enable disabled debug logging statements

See

• log4j manual
• slf4j