RFR: 8360070: AccessibleText.getBeforeIndex returns null for last character

[Abhishek Kumar]

On Tue, 24 Jun 2025 23:00:03 GMT, Sergey Bylokhov <serb at openjdk.org> wrote:

> > I think the check is to ensure the passed index parameter is to verify the boundary of text length.
> 
> Yes, but the index passed to the method is `an index within the text`, so it should be from 0 to length - 1. You can take a look at the opposite case when the index is outside the range, for example at the beginning of the text and getAfterIndex:
> 
> > result = at.getAfterIndex(AccessibleText.CHARACTER, -1);
> > verifyResult("T", result);
> 
> Is that expectation correct or not? I think we should first decide whether this is actually a bug or not.

I got your point now. The spec says that `index an index within the text` and that means the value should range from 0 to length - 1. And that means, `getBeforeIndex` won't be able to fetch the last character and `getAfterIndex` won't be able to fetch the first character.

So, if someone wants to retrieve the first or last character, they shouldn't rely on `getAfterIndex and getBeforeIndex` method respectively, rather use `getAtIndex` method to get the first and last character with index passed as 0 and length -1 respectively.

Right ?

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PR Comment: https://git.openjdk.org/jdk/pull/25941#issuecomment-3003204161