Java Checkstyle / Spotless (Codex agent)

OpenMetadata enforces Java formatting via the Spotless Maven plugin. Every CI build runs mvn spotless:check and fails the PR if any file is not formatted.

When to activate

• The user asks to "fix checkstyle", "fix Java formatting", "apply spotless",

"run spotless", "format Java", or similar.

• CI posts a Java checkstyle failed / Fix Java checkstyle comment on a PR

(the bot's exact phrasing is "Please run mvn spotless:apply in the root of your repository and commit the changes to this PR").

• After you have finished authoring or editing any .java files — before

opening a PR or pushing a commit that touches Java.

Procedure

1. From the repo root run Spotless:

   mvn spotless:apply                 # formats everything
   # or
   mvn -pl <module> spotless:apply    # scope to a single Maven module for speed
   # or
   mvn spotless:check                 # verify only, without rewriting files

Spotless is fast (seconds, no compilation). If it fails with a plugin error rather than a formatting diff, surface the error and stop — do not try to hand-edit formatting around the failure.

1. Inspect the diff:

   git status --short
   git diff --stat

Expect changes only in .java (and possibly pom.xml) files. If Spotless keeps rewriting a change you just made, re-read the root pom.xml's spotless-maven-plugin config — Spotless is the source of truth, not the IDE.

1. Only commit if the user asked to. Report the changed-file list first so the

user can decide whether to fold the reformat into the in-progress commit or make a separate "Fix Java checkstyle" commit (matches the repo's existing history for bot-triggered formatting-only commits).

Out of scope

• UI / TypeScript formatting — use yarn pretty / ESLint flow (see AGENTS.md

UI section).

• Python formatting — use make py_format (black + isort + pycln).