Jigsaw is finally being incorporated into mainline JDK9. These long-awaited components should arrive before the end of this month.

Project Jigsaw has been long promised as a way to let Java programmers write code consisting of independent modules. The goal of Jigsaw is to define a standard module system for the Java platform and use that to modularize the platform itself and applications. Jigsaw, along with Lamda and Coin, was originally intended to be in Java 7 and all three of these were held over to be in Java 8. While the other two projects made it into Java 8, Jigsaw was again omitted and is only now finally being added to the mainline JDK development branch. 

The news was announced to the jdk9-dev mailing list by Alan Bateman of Oracle's Java Platform Group, who said in an email to the list that a snapshot version of the Jigsaw module system is being incorporated into the mainline JDK9 development branch.

The plan is to integrate during the week of March 21 for JDK-9+111, keeping the week of March 27 for jdk-9+112 as backup in the event of issues.

According to the email:

"The proposal is to integrate directly into jdk9/jdk9 (master) and then immediately sync up jdk9/dev with the other forests to follow. The rational for going directly into master is that this is a large change and we would like it to be the only change in the weekly build. This is our third major milestone on this project, we integrated directly in master for the previous two milestones (JEP 201 and JEP 220) too."

Because of the need to develop both the JDK 9 classes and Jigsaw without problems from overlapping, Jigsaw has until now been developed in a separate forest. Putting the Jigsaw elements back into the JDK forests could be tricky, hence the lock down of the mainline JDK build while the integration takes place. However, some changes have already been carried out, including the removal of the PropertyChangeListeners.

The Jigsaw modules will continue being changed in the Jigsaw forest, meaning developers using the mainline JDK9 can be confident of smooth running.

More Information

JDK Mailing List Announcement

Jigsaw Spec State Of The Module System

Related Articles

JDK 9 Update

JDK 9 Early Access Now Available

Java JDK 9 Proposals

Jigsaw Shelved Until Java 9

Java 8 Launched With Supporting Line-Up

To be informed about new articles on I Programmer, sign up for our weekly newsletter,subscribe to the RSS feed and follow us on, Twitter, Facebook, Google+ or Linkedin. 

Comments

Make a Comment or View Existing Comments Using Disqus

or email your comment to: comments@i-programmer.info