Stabilize JDK 10 Java CI

[shps951023]

Summary

• keep Maven and packaging on JDK 17 while running the JDK 10 compatibility test JVM in interpreter mode
• prefer WenQuanYi Micro Hei before GNU Unifont for non-subset JDK 10 CJK rendering
• upload Surefire and HotSpot diagnostics automatically if the JDK 10 job fails again

Root cause

The obsolete HotSpot 10 runtime is unstable in compiled mode across heterogeneous hosted-runner CPUs. Changing vendors, retrying, disabling container detection, and changing Surefire launch modes did not make compiled execution reliable. Diagnostic runs also exposed incomplete Simplified Chinese extraction when GNU Unifont was selected as the primary non-subset fallback.

Maven remains on JDK 17 so normal packaging and shade verification are unchanged. Only the JDK 10 test fork uses -Xint, which removes the unstable JIT path while still running the complete compatibility suite on Java 10.

Validation

• focused PageSize test in forked interpreter mode: 3 passed
• focused XLSX renderer tests: 4 passed
• local regression suite: 83 tests, 0 failures, 0 errors, 5 environment skips
• Java CI run 35948232104: all 18 matrix jobs passed
• rerun of 35948232104: all 18 matrix jobs passed
• general CI build and AI security scan passed
• git diff --check origin/main...HEAD

Summary by CodeRabbit

• Bug Fixes
  • Updated fallback font selection for CJK text when font subsetting is disabled. The renderer now checks WQY Micro Hei first, followed by Unifont and Noto Sans SC Variable, which may change the appearance of CJK text where earlier fallback fonts are unavailable. Other fallback choices and the selection order when font subsetting is enabled remain unchanged.

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ℹ️ Recent review info

⚙️ Run configuration

Configuration used: defaults

Review profile: CHILL

Plan: Advanced

Run ID: 0e9305d4-fcb4-4f6d-9454-7914658da117

📥 Commits

Reviewing files that changed from the base of the PR and between f154bc0 and 8340a44.

📒 Files selected for processing (2)

• .github/workflows/java-ci.yml
• minipdf-java/minipdf/src/main/java/io/github/minisoftware/minipdf/internal/xlsx/PoiXlsxRenderer.java

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📝 Walkthrough

Walkthrough

The pull request updates JDK 10 CI test execution and failure artifact collection. It also changes the search priority for CJK system fonts when font subsetting is disabled.

Changes

JDK 10 CI

Layer / File(s)	Summary
JDK 10 test execution and failure artifacts .github/workflows/java-ci.yml	The JDK 10 job runs Maven verification with updated JVM arguments. On failure, it uploads Surefire reports and JVM crash logs, with a three-day retention period.

CJK font search order

Layer / File(s)	Summary
Non-subset font priority minipdf-java/minipdf/src/main/java/io/github/minisoftware/minipdf/internal/xlsx/PoiXlsxRenderer.java	When font subsetting is disabled, wqy-microhei.ttc is checked before unifont.ttf and NotoSansSC-VF.ttf. The remaining candidates and the subsetting-enabled order are unchanged.

Priority: ⬇️ Low

Estimated code review effort: 2 (Simple) | ~10 minutes

Change: Bug fix

Merge Risk: ⚪ Minimal · up to 8340a

No concrete issue remains that should block merging. Font coverage on the JDK 10 runner remains unverified.

🚥 Pre-merge checks | ✅ 4 | ❌ 1

❌ Failed checks (1 warning)

Check name	Status	Explanation	Resolution
Docstring Coverage	⚠️ Warning	Docstring coverage is 0.00% which is insufficient. The required threshold is 80.00%. Docstring coverage is scoped to functions touched by this diff. Analyzed 1 functions across 1 files. (1 skipped: 1 …	Write docstrings for the functions missing them to satisfy the coverage threshold.

✅ Passed checks (4 passed)

Check name	Status	Explanation
Description Check	✅ Passed	Check skipped - CodeRabbit’s high-level summary is enabled.
Title check	✅ Passed	The title clearly and concisely describes the main change: stabilizing the JDK 10 Java CI workflow. It matches the primary pull request objective.
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.

Full details: Docstring Coverage

Explanation

Docstring coverage is 0.00% which is insufficient. The required threshold is 80.00%. Docstring coverage is scoped to functions touched by this diff. Analyzed 1 functions across 1 files. (1 skipped: 1 unsupported.)

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✨ Finishing Touches 💡 1

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