Java State Exploration Tool Mike Lawson CS522 Fall 2004

Overview Introduction / Requirements Why Did I Do This Project? Demo Things To Do References

Intro / Requirements Create a Version of SETool in Java to Implemented Reachability Analysis (RA) Run From Click of a Link Allows User to Draw CFSMs Graphically Depict Results Allow User to Save and Load CFSMs, Results

Use Cases

Why? Force Me to Figure Out RA Kept Messing it Up – homework/midterm “Fun” with Java 2D Explore Ways to Distribute Portable Java Applications via Web I like to Make Things “GO!” If You Click a Link, it Should Do Something Web-Like

“Fun” With Java 2D Java 2D Provides Foundation e.g. Rectangle, Line, Transforms, etc. Tedious, Tedious, Tedious to Implement Dragging, Dropping, Connecting … Don’t Do it Yourself Get GEF Java Graphical Editing Framework Link in References I Didn’t Use GEF to Keep Product Small

Distribute Java Applications Variety of Means Download and Go Applets Java Web Start

Download and Go User Downloads Jar and Executes Good Easy to Distribute Can Easily Guarantee All Dependencies Are Present Bad Is the Programmer Evil/Malicious/Trustworthy? No Sandbox Hard to Keep Clients up to Date

Applets Back to Basics with Java Good Full HTML 1.1 Support with APPLET Just Put in HTML (no server side changes) Easy to Create and Deploy Sandbox Prevents Malicious Code Painful Display Size Limited in HTML Page Sandbox Prevents File I/O Workaround – Sign the Jar Always Need to be Connected (no offline) Almost Always Downloads Every Time User Hits Page Some Browsers will Cache for Session Requires A Priori Knowledge of JRE

Java Web Start (I’ve Ignored This for Years, Until Now) Introduced in Java 1.2 Allows a Web Page to Host Applications Sandbox Secure Applications Cached Locally Can Execute on Airplane, Harley, etc. Automatically Updated No A Priori JRE Version Required Need At Least Java 1.2 Can Declare Different Version to be Downloaded Automatically Declarative Security Painful Requires Server Side Changes Addition to MIME types in Web Server (blanca) Sandbox Prevents File I/O Sign Jar like in Applet Bandwidth Problems (56K might be sloooow)

Demo Look Ma, I’m Coding!

TODO Things to Be Done Class Cleanup Many Classes Resemble MouseListener, etc. Classes Too Big Problems with Saving/Loading Results Poise for Web Service, etc Show Max Queue Size on Summary Info is There, I Just Forgot to Show it XML Persistence Transmogrify to GEF My Drawing Implementation is Sometimes Painful Save/Load Projects Save as Image Load Examples from Web Pages Basic UI Stuff: Remember File Name, Enable Save after Change …

References Java Web Start vaws/developersguide/contents.html vaws/developersguide/contents.html Java Applets ng/components/applet.html ng/components/applet.html GEF