Numerical Command-Line Arguments in Java

Hi I am new to Java and am a little confused about setting up command-line arguments. From what I have read, the arguments are put in the args array of the main method.
So accessing or using them would use args[n] right?
But the args is a string array (String[] args). Therefore what would I need to do if I wanted to treat the arguments as numbers and not strings? E.g. I wanted to apply mathematical functions to the arguments.
I believe to do this I would need a Integer.parseInt( string ).
This is what I have tried:
public static void main(String[] args) {
          int firstArg = Integer.parseInt(args[1]);
          System.out.println(firstArg);
where argument 1 is "23".
This compiles but I get a Exception in thread "main" java.lang.ArrayIndexOutOfBoundsException: 1
     at the "int firstArg = Integer.parseInt(args[1]);" line.
Can someone tell me what I am doing wrong and a small over view on command line arguments would also be welcome :D.
Thanks

Oh yeah.. I need to tattoo args[0] to my forehead. Thanks its now working.
Edited by: Sunny_B on Apr 20, 2008 1:21 PM

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