docs/source/contributor-guide/code-style.md

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# Code style

To apply Java + Rust formatters in one go:

```sh
make format
```

CI verifies formatting, lint, and license headers on every PR via the
**Lint** and **RAT License Check** workflows.

## Java

Spotless is configured in the parent `pom.xml`. The CI `fmt-check` job
runs:

```sh
./mvnw spotless:check
```

## Rust

The CI `clippy` job runs (from `native/`):

```sh
cargo fmt --all -- --check
cargo clippy --all-targets -- -D warnings
```

`-D warnings` escalates every clippy warning to a build failure.

## License headers

Every tracked source file needs the Apache 2.0 license header. The
**RAT License Check** workflow runs `./mvnw -N apache-rat:check` on every
PR (including docs-only changes). Exclusions live in
`dev/release/rat_exclude_files.txt`.