I am new to Java. I use NetBeans 7.1 IDE on Windows Vista. I try my first Hello World Program:

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package javaapplication1;

* @author Bilal Gharib
public class JavaApplication1 {

* @param args the command line arguments
public static void main(String[] args) {
System.out.println("Hello World!");

When I run the program, nothing happens!
I also tried to build the jar file; although it was built successfully, yet when I try to run it, again nothing happens.

I am completely new to Java.

Thanks to any help.