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	Writing Java(tm)-Compatible Applets in Ada 95 by S. Tucker Taft
	Intermetrics, Inc. 733 Concord Avenue, Cambridge, MA 02138 USA Phone: +1 (617) 661-1840 - Fax: +1 (617) 868-2843 Email: stt@inmet.com

Abstract:	This tutorial/workshop will introduce the attendees to writing Java(tm)-compatible applets in Ada 95. Java(tm) is a new technology from Sun (see http://www.javasoft.com/) which allows small applications ("applets") to be automatically downloaded to a client machine as part of browsing an HTML Web page with a Java-enabled Web browser. As of this writing, Sun's own HotJava(tm) browser, Netscape's Navigator browser, and Spyglass' Enhanced Mosaic browser are all going to support Java-compatible applets. Sun has designed a new object-oriented language called "Java" as part of this technology, and provides a compiler to translate Java source programs into a byte-code representation (herein called "J-code") for secure and efficient transmission across the Internet. When a Java-enabled browser encounters an HTML Web page with a reference to a Java applet (via the HTML tag "<applet ...>"), the J-code for the applet is automatically downloaded and executed, giving it control over a specified part of the screen displaying the Web page. J-code is a platform independent byte-code, and is intended for efficient execution by an interpreter, or efficient on-the-fly translation to machine-code for execution by the client hardware. Although the source language Java and the Java byte code were designed hand-in-hand, it is still possible to map other programming languages to J-code, provided the underlying semantics of the languages match those of Java relatively well. As it turns out, the semantics of Ada 95 fit remarkably well the underlying capability of J-code. Recognizing this, a group at Intermetrics is in the process of adapting our validated Ada 95 front end ("AdaMagic"(tm)) to directly generate J-code, allowing Java-compatible applets to be implemented in Ada 95.
Outline:	Introduction to Sun's Java(tm) technology The Java language The Java virtual machine The standard Java classes Introduction to the Intermetrics Ada95/Java compiler An overview of the mapping of Ada to J-code; Programming and naming conventions for source-level interoperability between Java packages/classes and Ada 95 packages/types; Using the compiler with a Java-enabled browser, the Java interpreter, or a Java applet viewer. Writing applets in Ada 95 The basics -- Hello world Using Java threads/Ada tasks for animation -- the game of Life Creating long-lived applets in their own "frame" -- a desk calculator The future of Ada 95 and Java on the Web Establishing repositories of reusable applet components Creating full Web-based client/server systems in Ada 95 Supporting other languages via J-code (Smalltalk, Scheme, etc) -- a true multilingual programming culture?
Background:	Designed for Ada 95 programmers who have some familiarity with the World Wide Web.
Biography:	S. Tucker Taft has been actively involved with Ada since September 1980. From March 1990 to February 1995 Mr. Taft led the design team for Ada 9X, which we now know as Ada 95. He is chief scientist in the Cambridge office of Intermetrics, Inc., and is chief architect of Intermetrics' Ada 95 technology, called AdaMagic(tm).