Lecture : Introduction to Multimedia & Java

In the previous lecture:

There was no previous lecture... this is the first one so please have a look over the:

• course home page
• course outline
• lecture notes summary table
• assignment information
• what's new?

In this lecture:

• What are media and what are they used for?
• What is Java? What is it used for and how is it used?
• What is this course all about and how can you do well in it?

About Multimedia

What do we mean by medium, media and multimedia?

A medium is a substance (e.g. air / water) through which something (e.g. light / sound / information / a message from the dead) is conveyed. med - middle, that which stands between. Please note that media is the plural form of medium.

Example applications for media for conveying information or messages to humans:

A theatre production with shadow puppets projected as a backdrop, music played by an orchestra and singing, dancing actors is a multimedia production — multimedia doesn't require any digital technology!

Dynamic media are media that change (as opposed to static media that remain fixed).

Interactive media are media that permit humans to alter the way they change.

Skills learned in this course will be applicable when designing...

Control panels and displays	Computer games
Information kiosks	2D graphing and drawing software
Architectural & 3D modelling software (Image © Texas A&M University, Collecge of Architecture)	3D Scientific visualisation software (Image © David Bock)
Scientific simulation software (Image © Adaptive Care Systems)	Interactive media art
Interactive museum exhibitions (Image of VROOM at the Melbourne Museum)	...and a huge variety of more "everyday" items.

The combination of multiple media requires not only a thorough understanding of each of them, but also experience in their combination, and an understanding of their relationship with the message being conveyed...

....and that is what this course is all about!

About Java

Components of Java The Java Programming Language (for writing Java applications, applets, servlets and JavaBeans) Object-oriented language with a syntax similar to C that avoids some "dangerous" aspects of C/C++ programming The Java compiler (part of the Java Software Development Kit (SDK)) takes Java programs and compiles them into... Java Bytecode, an intermediate machine code for a "virtual machine" that will be translated into machine language for a real machine by... The Java Interpretter or Java Virtual Machine (JVM) Java programs are portable to any machine for which a Java interpretter has been written (e.g. Linux, MacOS, Windows, PalmOS...) The JVM uses just in time compilation to convert Java bytecode into a machine language program that is executed on the real computer that is running the JVM

Stages from written Java code to execution.

Also... The Java Platform is a set of Java classes organised into packages for providing functionality for common tasks through an Application Programming Interface (API) (e.g. I/O, networking, graphics, user-interface design...) javadoc is a tool that generates HTML documentation from Java source files. Documentation will be generated from "documentation comments" in your source code denoted /** like this */

Java "Hello World"

Login to your Unix account and type the following code into a file called, HelloWorld.java using a text editor such as vi (do not use a word processor in Windows... it isn't suitable for this application).

public class HelloWorld
{
     public static void main(String[] args)
     {
          System.out.println("Hello World!");
     }
}

The file name for the file must always match the name of the public class (in this case that's HelloWorld) with a .java extension.

Compile the code using the Java compiler by typing the following at the command-line prompt:

> javac HelloWorld.java

This will produce a file HelloWorld.class (the Java bytecode file). Execute the program using the Java interpretter by typing the following at the command-line prompt:

> java HelloWorld

and the program should print out:

> Hello World!

This is how you will need to write, compile and execute all of your programs for this course. Please don't use an integrated development environment (IDE). All of your assignments must run from the command-line (or later, when we get up to applets, from within a web-browser) under Unix/Linux.

In your own time investigate and try out:

1. jar the Java Archive Tool. You will need to use this to submit your assignment part 2.
2. jdb the Java debugger. This might make debugging your code easier than if you use print statements.

Java developer resources for you to install on your home computer are available from http://java.sun.com