RFR: 7904021: Parsing group files(TEST.GROUPS) on non-UTF-8 encoding platforms fails with java.nio.charset.MalformedInputException

[Christian Stein]

On Thu, 5 Jun 2025 04:35:14 GMT, Pasam Soujanya <duke at openjdk.org> wrote:

> Parsing group files(TEST.GROUPS) on non-UTF-8 encoding platforms fails with java.nio.charset.MalformedInputException.
> 
> Error:
> Error: Cannot read group files for /test/jdk: java.nio.charset.MalformedInputException: Input length = 1
> ---------
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> ### Error
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> ### Integration blocker
>  ⚠️ Title mismatch between PR and JBS for issue [CODETOOLS-7904021](https://bugs.openjdk.org/browse/CODETOOLS-7904021)
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Looking at the former implementation, without NIO API usage, the file read by those methods were assumed to be encoded in `ISO 8859-1`. Defaulting to `UTF-8` was a breaking change, although storing files in `UTF-8` nowadays is a common pattern.

Using `Charset.defaultCharset()` as proposed in the pull request introduces yet another behaviour. Maybe better? Another solution would be to revert to use the original `ISO 8859-1`. 🤔

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PR Comment: https://git.openjdk.org/jtreg/pull/267#issuecomment-2956997051