How to input 2 numbers to the program?

Question

Dear all,
I am learning converting from http://java.sun.com/docs/books/tutorial/java/data/converting.html. I use netbean, and I copy and paste the code from the web. I choose "run file" in netbean. I know I need to input two numbers to run this program, However, I don't know how to do it in netbean
Moreover, what exactly "public static void main(String[] args) " mean? especially (String[] args)
* Main.java
* Created on June 14, 2007, 10:50 AM
* To change this template, choose Tools | Template Manager
* and open the template in the editor.
package converting;
* @author Marco
public class Main {
    /** Creates a new instance of Main */
    public Main() {
     * @param args the command line arguments
    public static void main(String[] args) {
        // TODO code application logic here
            if (args.length == 2) {
               //convert strings to numbers
            float a = (Float.valueOf(args[0]) ).floatValue(); 
            float b = (Float.valueOf(args[1]) ).floatValue();
            //do some arithmetic
            System.out.println("a + b = " + (a + b) );
            System.out.println("a - b = " + (a - b) );
            System.out.println("a * b = " + (a * b) );
            System.out.println("a / b = " + (a / b) );
            System.out.println("a % b = " + (a % b) );
        } else {
           System.out.println("This program requires two command-line arguments.");

Answer 1

args[] is a String array so when you do:
// calling MyClass with 3 parameters
java MyClass arg1 arg2 arg3you can retreive the parameters with for loop
if(args.length < 3){
  System.out.println("use: java [options] <yourClass> param1 param2 param3");
  System.exit(0);
}else{
  for(String str:args){
    System.out.println(str);
...