Helidon: Java Libraries for Microservices

Project Helidon is a set of Java Libraries for writing microservices. Helidon supports two programming models:

• Helidon MP: MicroProfile 6.0
• Helidon SE: a small, functional style API

In either case your application is a Java SE program running on the new Helidon Níma WebServer that has been written from the ground up to use Java 21 Virtual Threads.

In Helidon 4 each request is processed by a dedicated virtual thread so your code is free to perform blocking operations without impacting your server's ability to handle other requests. You get all the throughput of a reactive server with none of the complexity.

License

Helidon is available under Apache License 2.0.

Documentation

Latest documentation and javadocs are available at https://helidon.io/docs/latest.

Helidon White Paper is available here.

Get Started

See Getting Started at https://helidon.io.

Downloads / Accessing Binaries

There are no Helidon downloads. Just use our Maven releases (GroupID io.helidon). See Getting Started at https://helidon.io.

Helidon CLI

macOS:

curl -O https://helidon.io/cli/latest/darwin/helidon
chmod +x ./helidon
sudo mv ./helidon /usr/local/bin/

Linux:

curl -O https://helidon.io/cli/latest/linux/helidon
chmod +x ./helidon
sudo mv ./helidon /usr/local/bin/

Windows:

PowerShell -Command Invoke-WebRequest -Uri "https://helidon.io/cli/latest/windows/helidon.exe" -OutFile "C:\Windows\system32\helidon.exe"

See this document for more info.

Build

You need JDK 21 to build Helidon 4.

You also need Maven. We recommend 3.8.0 or newer.

Full build

$ mvn install

Checkstyle

# cd to the component you want to check
$ mvn validate  -Pcheckstyle

Copyright

# cd to the component you want to check
$ mvn validate  -Pcopyright

Spotbugs

# cd to the component you want to check
$ mvn verify  -Pspotbugs

Documentatonn

# At the root of the project
$ mvn site

Build Scripts

Build scripts are located in etc/scripts. These are primarily used by our pipeline, but a couple are handy to use on your desktop to verify your changes.

• copyright.sh: Run a full copyright check
• checkstyle.sh: Run a full style check

Get Help

• See the Helidon FAQ
• Ask questions on Stack Overflow using the helidon tag
• Join us on Slack: #helidon-users

Get Involved

• Learn how to contribute
• See issues for issues you can help with

Stay Informed

• Twitter: @helidon_project
• Blog: Helidon on Medium