GSoC 2026 - Java 25 Language Feature Support

[Vivek Singh solanki]

Monday, 6 July report

What I did in the sixth week:

This week I focused on fixing NPEs and false negatives for the compact source file support feature, and on expanding the audit with newly found issues.

Worked on the following issues:

• https://github.com/checkstyle/checkstyle/issues/20218 - Fix false negative on JEP 512 compact source files (MissingJavadocMethod)
• https://github.com/checkstyle/checkstyle/issues/20523 - Fix NullPointerException on JEP 512 compact source files (FinalClass)
• https://github.com/checkstyle/checkstyle/issues/20524 - Fix NullPointerException on JEP 512 compact source files (AbbreviationAsWordInName)
• https://github.com/checkstyle/checkstyle/issues/20224 - Fix false negative on JEP 512 compact source files (JavadocStyle)

I also opened new issues found during a wider audit of all checks against compact source files:

Two new NPE issues:

• https://github.com/checkstyle/checkstyle/issues/20523 - FinalClassCheck: NullPointerException on compact source files
• https://github.com/checkstyle/checkstyle/issues/20524 - AbbreviationAsWordInNameCheck: NullPointerException on compact source files

Three more new false negatives:

• https://github.com/checkstyle/checkstyle/issues/20553 - ClassFanOutComplexityCheck: fan-out of implicit class not measured
• https://github.com/checkstyle/checkstyle/issues/20552 - CovariantEqualsCheck: covariant equals on top-level method not flagged
• https://github.com/checkstyle/checkstyle/issues/20555 - WriteTagCheck: first top-level method's Javadoc tags not reported