8058779: Faster implementation of String.replace(CharSequence, CharSequence)

[Ulf Zibis]

Am 31.05.2015 um 08:38 schrieb Peter Levart:
> Hi,
>
> Yes, this one is much easier to grasp.
>
> As I understand the check is to avoid overflow in calculation of StringBuilder initial capacity 
> (newLenHint). If overflow happened, newLenHint would be negative and StringBuilder construction 
> would fail with NegativeArraySizeException. But the calculation of newLenHint:
>
>     int newLenHint = value.length - targLen + replValue.length;
>
> ...considering the following:
>
>     value.length >= 0
>     targLength >= 0
>     replValue.length >= 0
>     targLength <= value.length
>
> in case of overflow, it can only produce a negative value. So the check could simply be:
>
>     if (newLenHint < 0) {
>         throw new OutOfMemoryError();
>     }

Hm, what has this situation to do with Out-Of-Memory ?

In other words, IMHO NegativeArraySizeException is much better here and additionally saves performance.
Additionally you could propagate it to InvalidArgumentException.

-Ulf