RFR: 8330462: StringIndexOutOfBoundException when typing anything into TextField [v9]

[Andy Goryachev]

On Fri, 19 Apr 2024 18:32:06 GMT, Oliver Kopp <duke at openjdk.org> wrote:

>> modules/javafx.graphics/src/main/java/com/sun/glass/ui/win/WinTextRangeProvider.java line 378:
>> 
>>> 376:         if (text == null) return null;
>>> 377:         validateRange(text);
>>> 378:         int endOffset = getValidStringIndex(start, maxLength, end);
>> 
>> If I presume the arguments are (start, length, maxLength), the last two arguments on this line only need to be swapped.  They seem to be correct on LL 394, 498.
>
> `maxLength` is the parameter of the `GetText` method. The caller asks for the text, but only with `maxLength` length. Therefore, `start + maxLength`. `end` is the real end of the current string. After `end` there are no characters. Ensured by `validateRange`.
> 
> I can add a comment. I love to add comments, but I learned at https://github.com/openjdk/jdk/pull/10704 that only higher-level comments are desired...

I think the comment in https://github.com/openjdk/jdk/pull/10704 referred to an external project, so it was deemed as unrelated.

but this method, I feel, is rather convoluted.  why do we need to catch exceptions (malloc!) when we should be able to implement the required functionality with a few `if`s.

So I really have two comments: a) the code looks way too complex and b) if an average developer (like me) cannot figure out what it does within 10 seconds, a good comment would help.

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PR Review Comment: https://git.openjdk.org/jfx/pull/1442#discussion_r1572773987