On Fri, 2 Dec 2022 12:44:18 GMT, Sergey Tsypanov <[email protected]> wrote:
> I found out that this code
>
> public class Main {
> public static void main(String[] args) {
> String s = "Hello world!";
> char[] chars = s.toCharArray();
> int point = Character.codePointAt(chars, -1, 1);
> }
> }
>
> throws `ArrayIndexOutOfBoundsException` instead of JavaDoc-specified
> `IndexOutOfBoundsException`:
>
> Exception in thread "main" java.lang.ArrayIndexOutOfBoundsException: Index -1
> out of bounds for length 12
> at java.base/java.lang.Character.codePointAtImpl(Character.java:9254)
> at java.base/java.lang.Character.codePointAt(Character.java:9249)
> at org.example.Main.main(Main.java:7)
>
> and the method doesn't check whether `index` parameter is negative:
>
> public static int codePointAt(char[] a, int index, int limit) {
> if (index >= limit || limit < 0 || limit > a.length) {
> throw new IndexOutOfBoundsException();
> }
> return codePointAtImpl(a, index, limit);
> }
>
> I suggest to check the `index` parameter explicitly instead of relying on
> AIOOBE thrown from accessing the array with negative index.
Please add a test to `test/jdk/java/lang/Character/Supplementary.java`
-------------
PR: https://git.openjdk.org/jdk/pull/11480
