J1 module demo plans?

[Mark Reinhold]

> Date: Tue, 05 May 2009 09:41:20 -0400
> From: karen.kinnear at sun.com

> What are our current plans for a J1 demo? What have we gotten done
> for that and what is left?

The current plan for the J1 demo is to show the download-size and
native-packaging benefits of Jigsaw on Ubuntu Linux.  The main tasks
are:

  (1) A quick-and-dirty "modularization" of the JDK, done by shuffling
      around the files from a regular JDK build rather than by rewriting
      the JDK makefiles (Mark)

  (2) Add whatever remaining run-time features are needed for (1), e.g.,
      resources, native libraries, and possibly commands (Mark)

  (3) Write the packaging tool, jpkg, so that we can create .deb files
      from modules (Dalibor)

  (4) Upgrade javac to understand -modulepath and the new modularized
      output-directory format (Jon)

  (5) (Stretch goal) Upgrade javac to resolve dependences against a
      module library (Jon)

We can have a credible demo without (5), we just won't be able to show
how compile-time visibility checking works.

At this point I'm pretty sure we won't need any further VM changes for
this demo, but I could be wrong.

The demo itself will go something like this:

  - Start with an Ubuntu box that has no Java installed on it.

  - Using Synaptic, install the "bootstrap" JRE from a nearby package
    repository.  While selecting the package, compare its size to a
    currently-available full-JRE package.

  - Show that this minimal JRE can run the usual command-line "Hello,
    world!" program, packaged as an ordinary stand-alone class file
    rather than a module.

  - Show that it can't run even a trivial Swing application.

  - Install the Swing package, which in turn will cause one or more
    intermediate packages (e.g., AWT/2D) to be installed.

  - Show that a simple Swing application can be run.

  - Repeat this pattern as desired to show the installation of
    additional components (e.g., XML, JAX-WS, ...).

  - Show how to write and run the command-line "Hello, world!"
    program as a module.

  - Show how to write a simple Swing application as a module.

We're not going to have any IDE support for the JSR 294 language
constructs in time for J1, so this will be an Emacs-and-shell sort
of demo.

- Mark