Presentation on Log4j

I had presented this some time back at my workplace. May be you'll find it useful.

Log4j Logging Mechanism

View SlideShare presentation or Upload your own. (tags: log4jjava)

Interesting Identifiers in Java

Ever seen a declaration like

_ _ = new _();

or call to a method like

System.out.println(_._());


Try this example, you'll see, these are valid java statements.
read on..

package test.identifiers;

/**
 * example that shows various legal identifiers
 * 
 * @author Kunal
 *
 */
public class LegalIdentifiers {

 int $1 = 1; // valid
 long _6 = 6L; // valid
 char t = '\t'; // of course valid, did u have any doubt ;)
 
 class t{
 } 
 t $;  // now here t is type & $ is object of type t

 class _{
  int _ = 0;
  int _(){ // method with name of constructor
   return _;
  }
 } 
 _ _ = new _(); // _ is an object of type _ (underscore)

 void display(){
  System.out.println(_._()); // interesting, isn't it?
 }
 // this is not a fill-in-the-blanks question
 // it actually compiles and runs :)

 // this means
 String String = "String";  // is valid
 // yes it is !!!
 // so you can have variable name same as class name
 
 public static void main(String[] args) {
  (new LegalIdentifiers()).display();
 }
}