Project Jigsaw

The goal of this Project is to design and implement a standard module system for the Java SE Platform, and to apply that system to the Platform itself and to the JDK.

This effort is guided by an in-progress requirements document. That document, together with the overall Jigsaw design, will be starting points for an eventual Java Platform Module System JSR.

This Project is sponsored by the Compiler Group.

History

The original goal of this Project was to design and implement a module system focused narrowly upon the goal of modularizing the JDK, and to apply that system to the JDK itself. We expected the resulting module system to be useful to developers for their own code, and it would have been fully supported for that purpose, but it was not at the outset intended to be an official part of the Java SE Platform Specification.

The growing demand for a truly standard module system for the Java Platform motivated expanding the scope of the Project, as described above, to produce a module system that can ultimately become a JCP-approved part of the Java SE Platform and also serve the needs of the ME and EE Platforms.

For background, please see the following blog entries:

• The massive, monolithic JDK
• Packaging Java code
• The Modular Java Platform
• Project Jigsaw

The most recent online public presentation of this work is "The Modular Java Platform & Project Jigsaw", given at Devoxx 2009.

Working documents

• Requirements
• Module declaration format (source form, binary form)
• Modules and javac (pdf)
• Module-file format
• Modular JAR files
• Native code
• Optional modules & methods
• Services
• Current javadoc
• Quick start guide

Community

• Mailing lists
  • jigsaw-dev
• Bloggers
  • Alex Buckley
  • Jonathan Gibbons
  • Mark Reinhold