about Enhanced For loop

Hi,

how can i loop 5 times in enhanced for loop...i think this is a drawback of enhanced for loop...

for(int i=o;i<=5;i++){
}// in enhanced for loop,how can i do this?...

in enhanced for loop...you need array or collection for looping right?

...please can any one explain me on this

The enhanced for loop is not designed for looping a specific number of times - it is designed for looping once for each item in a Collection. If you want to loop a specific number of times, use the original for loop format.

in enhanced for loop...you need array or collection for looping right?

Yes. If you don't have one, you wouldn't use the new syntax. I'm not sure I would call it a drawback, its just different behaviour.

... and don't use the enhanced for loop if you modify the looped-through collection inside the for-loop's body. Internally, Java uses Iterators for performing the enhanced for-loops, so modifications will result in a ConcurrentModificationException ...

Cheers,
Guido

[Guido Sautter]: and don't use the enhanced for loop if you modify the looped-through collection inside the for-loop's body. Internally, Java uses Iterators for performing the enhanced for-loops, so modifications will result in a ConcurrentModificationException ...

Well, your modifications may (quite possibly) result in a CME. It's not guaranteed. Throwing a CME is not a general property of collections - it' s a property of several specific commonly-used collection classes, such as ArrayList, LinkedList, HashSet, and a few others. Even for those, it's never guaranteed that CME will be thrown. But probably it will. So the advice here is sound - it's just expressed a little more strongly than it should be, in my opinion.

Originally posted by Mike Simmons:
Well, your modifications may (quite possibly) result in a CME. It's not guaranteed. Throwing a CME is not a general property of collections - it' s a property of several specific commonly-used collection classes, such as ArrayList, LinkedList, HashSet, and a few others. Even for those, it's never guaranteed that CME will be thrown. But probably it will. So the advice here is sound - it's just expressed a little more strongly than it should be, in my opinion.

I know CME are not guaranteed, the JavaDoc of almost every class in the JCF states this, but you're going to have this sort of trouble in practice. Even though a CME might not be thrown in some circumstances, in would be a concurrecnt modification to alternate a Collection in an enhanced for-lopp running over that very Collection, if resulting in a CME or not ...
[ July 22, 2008: Message edited by: Guido Sautter ]

As I said: "but probably it will". We're in agreement at this point.

Thanks