fix: validate message batch input

[gaoxiaolei-s59]

What is the purpose of the change

Fixes #10458

MessageBatch.generateFromList used Java assert statements to validate null and empty input. That made invalid input behavior depend on assertion settings, producing AssertionError when assertions are enabled or later NullPointerException when they are disabled.

This PR replaces the assertions with explicit IllegalArgumentException validation.

Brief changelog

• Validate null and empty message collections explicitly in MessageBatch.generateFromList
• Add unit coverage for null and empty message collection inputs

Verifying this change

• mvn -pl common -Dtest=MessageBatchTest -Dspotbugs.skip=true test

Note

A full mvn -pl common -Dtest=MessageBatchTest test run failed before surefire in this local environment because SpotBugs hit java.lang.UnsupportedOperationException: The Security Manager is deprecated and will be removed in a future release on the current JDK. The targeted test command above was used to verify the change.

[oss-sentinel-ai]

Review: Approved ✅

PR: #10459 — fix: validate message batch input
Type: Bug fix (2 files, +13/-2)

Assessment

Clean implementation that fixes #10458 by replacing assert statements with explicit validation.

Changes

• MessageBatch.java: Replaced assert messages != null and assert messages.size() > 0 with explicit IllegalArgumentException validation
• MessageBatchTest.java: Added two test cases covering null and empty message collections

Verdict

✅ Minimal, well-tested fix that ensures consistent behavior regardless of JVM assertion settings.

---

🤖 Automated review by oss-sentinel-ai

[codecov-commenter]

Codecov Report

✅ All modified and coverable lines are covered by tests.
✅ Project coverage is 47.99%. Comparing base (2319d2f) to head (b79e957).
⚠️ Report is 2 commits behind head on develop.

Additional details and impacted files

@@              Coverage Diff              @@
##             develop   #10459      +/-   ##
=============================================
- Coverage      48.11%   47.99%   -0.13%     
+ Complexity     13329    13291      -38     
=============================================
  Files           1377     1377              
  Lines         100632   100631       -1     
  Branches       12995    12994       -1     
=============================================
- Hits           48422    48293     -129     
- Misses         46289    46403     +114     
- Partials        5921     5935      +14     

☔ View full report in Codecov by Harness.
📢 Have feedback on the report? Share it here.

🚀 New features to boost your workflow:

• ❄️ Test Analytics: Detect flaky tests, report on failures, and find test suite problems.