aosp12/prebuilts/checkstyle/README.md

Checkstyle

Checkstyle is used by developers to validate Java code style and formatting, and can be run as part of the pre-upload hooks.

[TOC]

Running it

It can be invoked in two ways.

1. To check style of entire specific files: checkstyle.py -f FILE [FILE ...]
2. To check style of the lines modified in the latest commit: checkstyle.py

Projects used

Checkstyle

A development tool to help programmers write Java code that adheres to a coding standard.

• URL: https://checkstyle.sourceforge.io/
• Version: 7.4-SNAPSHOT
• License: LGPL 2.1
• License File: LICENSE
• Source repo: https://android.googlesource.com/platform/external/checkstyle

Git-Lint

Git-lint is a tool to run lint checks on only files changed in the latest commit.

• URL: https://github.com/sk-/git-lint/
• Version: 0.0.8
• License: Apache 2.0
• License File: gitlint/LICENSE
• Local Modifications:
  • Downloaded gitlint/git.py and git/utils.py files individually.

Pre-upload linting

To run checkstyle as part of the pre-upload hooks, add the following line to your PREUPLOAD.cfg:

checkstyle_hook = ${REPO_ROOT}/prebuilts/checkstyle/checkstyle.py --sha ${PREUPLOAD_COMMIT}

Note that checkstyle does not always agree with clang-format, and so it's best to only have one enabled for Java.

Disabling Clang Format for Java

In .clang-format add the following to disable format checking and correcting for Java:

---
Language: Java
DisableFormat: true
SortIncludes: false
---

In some versions of clang-format, DisableFormat doesn't stop the sorting of includes. So to fully disable clang-format from doing anything for Java files, both options are needed.