@codacy/tools-checkstyle-14

Table of Contents

• Overview
• Updating patterns
• Updating the Checkstyle version
• Development
• Notes for maintainers

Overview

Java style checker and static analysis tool using the Checkstyle fat JAR. Uses the CLI execution strategy -- spawns java -jar checkstyle-all.jar via spawnTool() and parses its XML output.

Updating patterns

# Re-fetch pattern metadata from the Codacy API
pnpm prefetch

# Commit the result
git add src/patterns.json

Pattern IDs follow the format Checkstyle_AvoidStarImport, Checkstyle_WhitespaceAround, etc. The check name is extracted from the FQCN source attribute (e.g. com.puppycrawl.tools.checkstyle.checks.imports.AvoidStarImportCheck becomes AvoidStarImport).

Updating the Checkstyle version

1. Update CHECKSTYLE_VERSION in src/adapter.ts
2. Update JAR_NAME and JAR_URL constants accordingly
3. Run pnpm prefetch to check for new/removed rules
4. Run pnpm test to verify compatibility
5. If the major version changes, create a new adapter package (checkstyle-11/)

Development

pnpm build    # Build with tsup
pnpm test     # Run tests (requires java in PATH + JAR in tools dir)

To install the Checkstyle JAR locally for testing:

mkdir -p /tmp/codacy-checkstyle-test-tools
curl -L -o /tmp/codacy-checkstyle-test-tools/checkstyle-14.1.0-all.jar \
  https://github.com/checkstyle/checkstyle/releases/download/checkstyle-14.1.0/checkstyle-14.1.0-all.jar

Notes for maintainers

• Checkstyle requires Java 11+ as a runtime. The adapter uses ensureJre() to download Adoptium Temurin JDK 21 if no system Java is found.
• The fat JAR is downloaded from GitHub releases via downloadJar() to ~/.codacy/tools/checkstyle-14/.
• Exit code 0 = no violations, >0 = violations found (parse XML), negative = error.
• XML output is on stdout (unlike cppcheck which uses stderr).
• error/@source is an FQCN like com.puppycrawl.tools.checkstyle.checks.imports.AvoidStarImportCheck. The adapter strips the package prefix and Check suffix to derive the check name.
• error/@column may be absent; defaults to 1 when missing.
• Line/column numbers in Checkstyle XML are already 1-based; no conversion needed.
• Some modules (Header, FileLength, LineLength, etc.) are global and must be placed under <module name="Checker"> rather than inside <module name="TreeWalker">. The adapter handles this split when generating config from patterns.
• Config file detection looks for checkstyle.xml in the repository root.
• When no local config and no patterns are specified, the adapter uses Checkstyle's built-in sun_checks.xml.
• Checkstyle prints Starting audit... and Audit done. to stderr; these are filtered out from the error output.