Read the book!
(this jumps to the wiki)
Jump to the project card wall
to see upcoming book and code changes (the card wall tracks Issues for the
project).
Some highlighted documentation pages:
Warning
For those using the DependencyCheck plugins for Gradle or Maven, over the July 1st weekend the upstream API for fetching security CVEs changed a major version, and stopped supporting older versions of the data. To get up to date, update to at least version 10.0.2 of either the Gradle or Maven plugin.
After the update, the first build will take a very long time, but should
perform normally afterwards.
And during the first week or so after this change, you may see multiple
connection failures as OWASP NVD is overloaded with projects all catching up
at the same time.
The Maven plugin shows progress as CVE records are pulled: to see progress
with the Gradle plugin, use the --info command-line flag.
Modern Java/JVM Build Practices is an article-as-repo on building modern Java/JVM projects using Gradle and Maven, and a starter project in Java (the advice works for non-Java languages on the JVM though details may change).
Important
See the wiki for all pages and sections. This README is only introduction, motivation, and project status. You can use the table of contents below to quickly jump to bits that interest you.
Regardless of what language(s) or build tool(s) you choose, and you should treat your build and your pipeline as worthy of your attention just as you would your project source code: If it doesn't build right for customers as it does for developers, you have something to think about.
I'm showing you practices and tools that help you make your build and pipeline to production as first-class the same as your own source code. An example of this philosophy for a non-Java language is Clojure.
Your focus, and the focus of this article, is best build practices and project hygiene, and helping you have local work that is identical in production. This project is agnostic between Gradle and Maven: discussion in each section covers both tools (alphabetical order, Gradle before Maven). See My Final Take on Gradle (vs. Maven) for an opinionated view (not my own).
This is not a JVM starter for only Java: I use it for starting my Kotlin projects, and substitute complilation and code quality plugins. Any language on the JVM can find practices and tips.
Note
Scala and Clojure have their own prefered build tools not covered here; however, the advice and examples for your build pipeline are intended to be just as helpful for those JVM languages. Groovy and Kotlin can use the examples directly (they both tend towards the Gradle option on build tools).
As a guide, this project focuses on:
- A quick starter for JVM projects using Gradle or Maven. Fork me, clone me, copy/paste freely! I am Creative Commons Public Domain Dedication (CC0).
- Discuss—and illustrate (through code)—sensible default practices; highlight good build tools and plugins
- Document pitfalls that turned up. Some were easy to address after Internet search; some were challenging (see "Tips" sections)
- Do not be an "all-in-one" solution. You know your circumstances best. I hope this project helps you discover build improvements you love. Please share with others through issues or PRs
- Shift problems left — Find issues earlier in your build—before you see them in production
- Make developer life easier — Automate build tasks often done by hand: get your build to complain (fail) locally before sharing with your team, or fail in CI before deployment
These can be summed up as a Software supply chain: ensuring reliable, trusted software from local development through ready-to-deploy: Build with confidence.
But ... you must judge and measure the advice here against your own systems and processes. Some things (many or most things) may work for you: keep an eye for things that do not work for you.
A project starter has several goals:
- Help a new project get up and running with minimal fuss.
- Show examples of best practices.
- Explain the why for choices, and help you pick what makes most sense for your project.
This starter project is focused on build:
- Easy on-ramp for new folks to try out your project for themselves
- Support new contributors to your project that they become productive quickly
- Support current contributors in the build, get out of their way, and make everyday things easy
This starter project has minimal dependencies. The focus is on Gradle and Maven plugins and configuration so that you and contributors can focus on the code, not on setting up the build.
- I'm not a great programmer; I'm just a good programmer with great habits. — Kent Beck
- Make it work, make it right, make it fast — C2 Wiki
Note
NB — This is a living document.
The project is frequently updated to pick up new dependency or plugin
versions, and improved practices; the README.md and
wiki update
recommendations.
This is part of what great habits looks like: you do not just show love
for your developers and users, but enable them to feed back into projects
and help others.
See Reusing this
project
for tips on pulling in updates.
(Credit to Yegor Bugayenko for Elegant READMEs.)
You should "kick the tires" and get a feel for what parts of this project you'd like to pull into your own projects and builds. You run across lots of projects: Let's make this one helpful for you.
After cloning or forking this project to your machine, try out the local build that makes sense for you:
$ earthly +build-with-gradle # CI build with Earthly
$ earthly +build-with-maven # CI build with Earthly
$ ./gradlew build # Local-only build
$ ./mvnw verify # Local-only buildNotice that you can run the build purely locally, or in a container?
I want to convince you that running your builds in a container fixes the "it worked on my machine" problem, and show you how to pick up improvements for your build that helps you and others be awesome.
Note
This project uses NVD to check for CVEs with your dependencies which can take a long time to download. You can speed up your build time by requesting an NVD API key (it can take quite a while to fetch the CVEs list or update it, and may fail with 403 or 404 without a key).
When you request a key, NVD sends you an email to confirm your identity, and then share an API key web page. See Shift security left for more details.
See what the starter "run" program does:
Both Gradle and Maven (after building if needed) should print:
TheFoo(label=I AM FOOCUTUS OF BORG)
A "starter" program is the simplest of all possible "smoke tests", meaning, the minimal things just work, and when you check other things, maybe smoke drifts from your computer as circuits burn out1.
(For detailed changes in the example code, browse the commit log.)
- Move to a CC0 license from Public Domain.
- Gradle: Bump to Gradle 8.9.
- Migrate most of the
README.mdto the GitHub project wiki. This is breaks up an overlong (14k+ words and growing) README into digestible sections. - Earthly and Batect: Remove support for Batect as the author has archived
that project.
Please use Earthly for local containerized builds.
So your local command line is:
I'll be researching other options, and updating to show those and examples. Advice remains the same: Run your local build in a container for reproducibility, and have CI do the same to exactly repeat your local builds.
$ earthly +build-with-gradle # OR $ earthly +build-with-maven - JVM: Move to JDK 21. This project has no sample code relying on recent/modern versions of Java or the JVM; however, moving between versions does need changes to build scripts and supporting files. Here is the last commit using JDK 17
- Gradle: Build with Gradle 8.x.
- Gradle: Bemove use of
testsetsplugin for integration testing in favor of native Gradle support. This supports Gradle 8.
The writing for this project is fully moved to the wiki pages. Use the sidebar navigation in the wiki to browse or jump to topics, or to follow in a reading order. You can also use the droplist control next to "Pages" for an alphabetical listing (including subheaders within pages), and for a search box.
Lastly, the wiki pages are themselves a repo, and you can clone it using
git@github.com:binkley/modern-java-practices.wiki.git as you can for any
GitHub wiki.
See CONTRIBUTING.md.
Please file issues,
or contribute pull
requests!
I'd love a conversation with you.
Special thanks to my co-author, John Libby.
And many thanks to all the contributions from:
- Dan Wallach for multiple email reviews and discussions on security
- Kristoffer Haugsbakk
- Sam Gammon
- Sergei Bukharov
All suggestions and ideas welcome! Please file an issue. ☺
Footnotes
-
No, I'm just kidding. Amazon or Google or Microsoft cloud would have quite different problems than "white smoke" from computers2. ↩
-
Actually, this really happened me in a data center before the cloud when a power supply burned out. We rushed to use a fire extinguisher before the Halon system triggered. ↩