Replace new FileInputStream with Files.newInputStream()

[arturobernalg]

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[sebbASF]

What are the benefits of this change?
Any disadvantages?

[arturobernalg]

What are the benefits of this change? Any disadvantages?

It integrates seamlessly with the Path class, offers more flexible open options, and works well with try-with-resources for automatic resource management. In short, it’s a more robust, future-proof approach compared to the legacy FileInputStream.

[sebbASF]

AFAICT, it returns an InputStream rather than a FileInputStream. This means that some methods are not directly available. For example getFD, getChannel.
It does not look like this matters here, but it means the change is not entirely positive

[garydgregory]

This looks like an OK internal change from IO to NIO.

If you need a Channel from an input stream, just call java.nio.channels.Channels.newChannel(InputStream).

[jochenw]

I'm fine with changing, or leaving this, as it is.

A more deserving change would be, IMO, to introduce try-with-resources here.

[garydgregory]

The changes in this PR are not fully baked IMO. I pushed changes that use better NIO APIs, for example to read and write a file in one shot without having to create streams.