Juggling multiple Java platforms and Jigsaw with Gradle

Who am I

speaker {
    name 'Cédric Champeau'
    company 'Gradle Inc'
    oss 'Apache Groovy committer',
    successes 'Static type checker',
                    'Static compilation',
                    'Traits',
                    'Markup template engine',
                    'DSLs'
        failures Stream.of(bugs),
        twitter '@CedricChampeau',
        github 'melix',
        extraDescription '''Groovy in Action 2 co-author
Misc OSS contribs (Gradle plugins, deck2pdf, jlangdetect, ...)'''
}

Disclaimer

Work in progress
Will be backported to current model

Project Jigsaw

Modularity for the Java platform
- Reliable configuration (goodbye classpath)
- Strong encapsulation (goodbye com.sun)
Enforce strict boundaries between modules
- compile-time
- run-time

Why it’s going to break your apps

Exports are package based
A non-exported package is not visible to consumers
2 modules cannot export the same packages
2 modules cannot have the same internal packages

Death to split packages.

How Gradle will help?

Find a smooth migration path
Prepare today, migrate when ready

Gradle’s software model

Idea : we’re building software, so let’s model software
Describe what rather than how
Leverage conventions
Work in progress

A simple project

00:00-00:00

Internal APIs

00:00-00:00

Internal APIs maintenance nightmare

00:00-00:00

Declaring internal APIs

00:00-00:00

Declaring target platforms

00:00-00:00

Why does Gradle help?

Add targetPlatform 'java9'
Generate module descriptor automatically?
Profit!

Trying it out

00:00-00:00

What’s next?

Backport to "old" model
Automatic toolchain selection
Support for modulepath
Support for jimage and jlink
Support for modulepath
Toolchain provisioning

Be involved

Specs can be found on our GitHub repo

Gradle Inc

Motto: Build Happiness

Mission: To revolutionize the way software is built and shipped. We exist to end once-and-for-all the worst things about big software and restore the reason you got into coding in the first place.

We’re Hiring: Gradle is hiring front-end, back-end, and core software engineers. Visit gradle.org/jobs to apply.

Introducing Gradle Cloud Services

The first service, Gradle Build Scans, is now available.

Insights into your build
View and share via URL
Debug, optimize and refine
Analyze all of your builds

build scans

https://receipts.gradle.com/r/ylmkl3dxfypia

Stop by the Gradle Lounge and create a Build Scan!

Thank you!

Slides and code : https://github.com/melix/gradlesummit2016-jigsaw-gradle
Gradle documentation : http://gradle.org/documentation/
State of the module system: http://openjdk.java.net/projects/jigsaw/spec/sotms
Follow me: @CedricChampeau

Learn more at www.gradle.org

Who am I

Disclaimer

Project Jigsaw

Jigsaw modules

Declaring a module

A module

Why it’s going to break your apps

How Gradle will help?

Gradle’s software model

A simple project

Internal APIs

Internal APIs maintenance nightmare

Declaring internal APIs

Compile avoidance

Compile avoidance benefits

Declaring target platforms

Why does Gradle help?

Trying it out

What’s next?

Be involved

Gradle Inc

Introducing Gradle Cloud Services

Thank you!