String.lastIndexOf confused by unpaired trailing surrogate

[Xueming Shen]

6937112: String.lastIndexOf confused by unpaired trailing surrogate

Kinda guess that it might bring us some performance benefit to separate 
the supplementary handling
code out into its own method (to help the not that smart hotspot:-)?), 
but doubt it is really something
worth doing. At  least you dont have to have the redundant 
value/offset=this.value/offset.

Seems like you started to attach the "final" keyword to all 
"constants"...guess it's a hint to help smart
vm for further optimization. Is the hotspot doing something special in 
simple case like below?

-Sherman

Martin Buchholz wrote:
> For a change, here's an actual plain old "incorrect result" bug fix
> for String.lastIndexOf
>
> Sherman, please file a bug and review.
>
> http://cr.openjdk.java.net/~martin/webrevs/openjdk7/lastIndexOf/
>
> Also includes our usual performance-oriented fiddling.
>
> public class LastIndexOf {
>     public static void main(String[] args) {
>         int ch = 0x10042;
>         char[] bug = new char[3];
>         Character.toChars(ch, bug, 0);
>         bug[2] = bug[0];
>         System.out.println(new String(bug).lastIndexOf(ch));
>         bug[2] = '!';
>         System.out.println(new String(bug).lastIndexOf(ch));
>     }
> }
> ==> javac -source 1.6 -Xlint:all LastIndexOf.java
> ==> java -esa -ea LastIndexOf
> -1
> 0
>