HADOOP-18424. Fix org.apache.hadoop.io.ArrayWritable

[cndaimin]

When we store an array of string with "new ArrayWritable(String[] strings)", the "valueClass" will be "Text" while the actual value type is "UTF8". This will cause an error on deserialization of ArrayWritable.

[hadoop-yetus]

🎊 +1 overall

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			_ trunk Compile Tests _
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+1 💚	unit	18m 31s		hadoop-common in the patch passed.
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[ayushtkn]

UTF8 is deprecated and the class itself say "replaced by Text", so this fix makes sense to me.

But this code getting changed is from 2009, not sure if there are any legacy reasons for that?

Any pointers @omalley / @steveloughran

[steveloughran]

no idea. ask owen.

[steveloughran]

don't think we should be using wikipedia text even if it's interesting. just use something from our own docs

[github-actions]

We're closing this stale PR because it has been open for 100 days with no activity. This isn't a judgement on the merit of the PR in any way. It's just a way of keeping the PR queue manageable.
If you feel like this was a mistake, or you would like to continue working on it, please feel free to re-open it and ask for a committer to remove the stale tag and review again.
Thanks all for your contribution.