Fix misleading Javadoc for Aggregation.nth(int)

[piotrrzysko]

Description

The comment stated "non-null element" but the method defaults to NullPolicy.INCLUDE, meaning NULL values can be returned.

Checklist

• I am familiar with the Contributing Guidelines.
• New or existing tests cover these changes.
• The documentation is up to date with these changes.

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[coderabbitai]

No actionable comments were generated in the recent review. 🎉

ℹ️ Recent review info

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Run ID: 765e8161-daed-4fdc-ac7a-5e8a57c80c44

📥 Commits

Reviewing files that changed from the base of the PR and between 9c2ccdc and b5cde3f.

📒 Files selected for processing (1)

• java/src/main/java/ai/rapids/cudf/Aggregation.java

✅ Files skipped from review due to trivial changes (1)

• java/src/main/java/ai/rapids/cudf/Aggregation.java

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📝 Walkthrough

Summary by CodeRabbit

• Documentation
  • Clarified that selecting the nth element includes NULLs by default and added guidance pointing to the alternative API to control NULL handling.
  • Documentation-only update; no runtime behavior or public API signatures were changed.

Walkthrough

This PR updates the Javadoc for Aggregation.nth(int) to state NULLs are included by default and directs callers to nth(int, NullPolicy) to control NULL handling.

Changes

nth Aggregation Documentation Update

Layer / File(s)	Summary
nth aggregation NULL handling documentation java/src/main/java/ai/rapids/cudf/Aggregation.java	Replaced the nth(int) Javadoc to explicitly state NULL values are included by default and to reference nth(int, NullPolicy) for controlling NULL handling.

🎯 1 (Trivial) | ⏱️ ~2 minutes

🚥 Pre-merge checks | ✅ 5

✅ Passed checks (5 passed)

Check name	Status	Explanation
Title check	✅ Passed	The title accurately describes the main change—fixing misleading Javadoc documentation for the Aggregation.nth(int) method.
Description check	✅ Passed	The description is directly related to the changeset, explaining that the Javadoc comment incorrectly stated 'non-null element' when the method defaults to NullPolicy.INCLUDE.
Docstring Coverage	✅ Passed	Docstring coverage is 100.00% which is sufficient. The required threshold is 80.00%.
Linked Issues check	✅ Passed	Check skipped because no linked issues were found for this pull request.
Out of Scope Changes check	✅ Passed	Check skipped because no linked issues were found for this pull request.

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[davidwendt]

/ok to test 262ae67

[piotrrzysko]

@davidwendt thanks for taking a look at this PR!

CI fails with:

verify-copyright-cudf....................................................Failed
- hook id: verify-copyright
- exit code: 1
- files were modified by this hook

In file java/src/main/java/ai/rapids/cudf/Aggregation.java:3:43:
  *  SPDX-FileCopyrightText: Copyright (c) 2020-2025, NVIDIA CORPORATION.
warning: copyright is out of date

In file java/src/main/java/ai/rapids/cudf/Aggregation.java:3:29:
- *  SPDX-FileCopyrightText: Copyright (c) 2020-2025, NVIDIA CORPORATION.
+ *  SPDX-FileCopyrightText: Copyright (c) 2020-2026, NVIDIA CORPORATION.

This seems unrelated to the PR. Should I fix it in this PR?

[davidwendt]

@davidwendt thanks for taking a look at this PR!

CI fails with:

verify-copyright-cudf....................................................Failed
....
This seems unrelated to the PR. Should I fix it in this PR?

@piotrrzysko Yes. If you modify a file you are expected to update the copyright year at the top of that file.
https://github.com/rapidsai/cudf/blob/main/cpp/doxygen/developer_guide/DOCUMENTATION.md#copyright-license

[paul-aiyedun]

@davidwendt thanks for taking a look at this PR!
CI fails with:

verify-copyright-cudf....................................................Failed
....
This seems unrelated to the PR. Should I fix it in this PR?

@piotrrzysko Yes. If you modify a file you are expected to update the copyright year at the top of that file. https://github.com/rapidsai/cudf/blob/main/cpp/doxygen/developer_guide/DOCUMENTATION.md#copyright-license

@piotrrzysko Please execute pre-commit run --all-files and that will apply updates like this automatically. See https://github.com/rapidsai/cudf/blob/HEAD/CONTRIBUTING.md#using-pre-commit-hooks for more details about using pre-commit.

[davidwendt]

/ok to test 9c2ccdc

[davidwendt]

Builds are failing. We just need to wait until they are working again.

[davidwendt]

/ok to test b5cde3f

[davidwendt]

/ok to test bb6f0b8

[revans2]

Thanks for fixing my mistake.

[davidwendt]

Now waiting on #22549 to merge this

[davidwendt]

/ok to test 351312f

[davidwendt]

This PR is cursed.

[davidwendt]

/merge