Unexpected ArrayIndexOutOf BoundsException.

[Catherine austin]

I following code compiled fine but at runtime it threw ArrayIndexOutOf Bounds Exception . I am unable to figure out what went wrong.Here's the code

public class z {
   public static void main(String args[]) { 
      Integer intObj=Integer.valueOf(args[args.length-1]);
      int i = intObj.intValue();

      if(args.length > 1) 
         System.out.println(i);
      if(args.length > 0)
         System.out.println(i - 1);
      else 
         System.out.println(i - 2);
   }
}

Thanks in advance

[Maneesh Godbole]

What args did you pass?
Can you post the stack trace?

[Luigi Plinge]

If you don't pass in any arguments then you're trying to access element -1 of the array, which will cause an exception.

Also, Integer.valueOf is unnecessary unless you're using some ancient version of Java (see autoboxing).

edit: never mind, I too was confusing this Integer.valueOf(String) method with Intger.valueOf(int) - the latter of which is a waste of space since the compiler in Java 5 or later does it for you.

[Campbell Ritchie]

It is probably worth using valueOf after all, because it permits caching of small values.

[Catherine austin]

Yeah , i got u. Thanks

[Campbell Ritchie]

Well done

[Rob Spoor]

Although this valueOf method converts a String into an Integer, I think that parseInt would be better because it bypasses the Integer object and immediately turns the String into an int.

[Campbell Ritchie]

I was mistaking it for the Integer.valueOf(int) method.

Agree that for turning a String to an int parseInt() is a lot better.