Checkstyle/SpotBugs Violations Failing the Build in CI - Fix or Tune

Checkstyle and SpotBugs fail the build when they find violations above the configured severity. These are deterministic static-analysis gates - the same code yields the same findings every run, so a retry never helps.

What this error means

The build fails with You have N Checkstyle violations or SpotBugs ... Bugs found: N. The compile/test phases passed; only the analysis goal failed.

maven

[ERROR] Failed to execute goal org.apache.maven.plugins:maven-checkstyle-plugin:3.3.1:check
(checkstyle) on project app: You have 7 Checkstyle violations.
[INFO] app/src/main/java/com/example/Foo.java:14: Line is longer than 120 characters.

Common causes

Real violations introduced

New code breaks a configured rule (line length, unused imports, a SpotBugs bug pattern), and the check goal is set to fail on violations.

Rule set stricter than the codebase

Adopting a stricter config (or bumping the plugin) surfaces many existing violations at once, failing the build broadly.

How to fix it

Fix the reported findings

Address the specific file/line each tool reports; most are mechanical (imports, formatting, null checks).

Terminal

# Run locally to see and fix the exact findings before pushing
mvn -B checkstyle:check
mvn -B spotbugs:check

Tune severity or suppress deliberately

When a finding is a false positive, suppress it explicitly rather than disabling the gate.

pom.xml

<!-- SpotBugs exclude filter: suppress a vetted false positive -->
<FindBugsFilter>
  <Match>
    <Class name="com.example.Foo"/>
    <Bug pattern="EI_EXPOSE_REP"/>
  </Match>
</FindBugsFilter>

How to prevent it

Run Checkstyle/SpotBugs locally and in pre-commit, keep the rule set stable, and suppress only vetted false positives with documented filters.