Some GenericUDFs wrongly cast ObjectInspectors

[okumin]

What changes were proposed in this pull request?

We have some UDFs that don't correctly cast ObjectInspectors.

https://issues.apache.org/jira/browse/HIVE-27905

Why are the changes needed?

Because we'd like to show better error messages. It should be helpful for users, and administrators who are monitoring errors. The original message is too primitive.

0: jdbc:hive2://hive-hiveserver2:10000/defaul> select split(array('a,b,c'), ',');
Error: Error while compiling statement: FAILED: ClassCastException org.apache.hadoop.hive.serde2.objectinspector.StandardConstantListObjectInspector cannot be cast to org.apache.hadoop.hive.serde2.objectinspector.PrimitiveObjectInspector (state=42000,code=40000)

Does this PR introduce any user-facing change?

Yes. Error messages can change.

Is the change a dependency upgrade?

No.

How was this patch tested?

I added integration tests.

[ayushtkn]

this might be a problem in other places I believe, I see similar code in GenericUDFElt/GenericUDFLocate and many other places as well,
can we fix there as well?

[okumin]

@ayushtkn Thanks. Can I address all similar issues in this single ticket?

[ayushtkn]

Yep

[sonarqubecloud]

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[okumin]

@ayushtkn I changed the scope, checked all UDFs, and added validations to where we incorrectly cast ObjectInspectors. I checked them by my eyes and it is possible that I missed some other mistakes.
For your information, most UDFs don't raise ClassCastException. For example, GenericUDFElt has a validation before it uses ObjectInspector.

[ayushtkn]

LGTM

[okumin]

Thank you!