RFR: 8356420: Provide examples on wrapping System.in [v3]

[Chen Liang]

On Fri, 9 May 2025 21:29:09 GMT, Naoto Sato <naoto at openjdk.org> wrote:

>> With the introduction of `stdin.encoding` ([JDK-8350703](https://bugs.openjdk.org/browse/JDK-8350703)), some guidance for users to decode `System.in` would be desirable. Adding examples in the field description would help.
>
> Naoto Sato has updated the pull request incrementally with one additional commit since the last revision:
> 
>   Reflects another review comment

Oops, I meant the wrong constructor - the `FileReader(FileDescriptor fd)` one that does not have a charset overload.

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PR Comment: https://git.openjdk.org/jdk/pull/25155#issuecomment-2870021180