Java New Media com

8/8/2019 Java New Media com

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Copyright 1997-8 Alex Chaffee

Java: A to ZJava: A to Z

Delivered By:

Alexander Day Chaffee, Purple Technology

Original Creator of Gamelan

(http://java.developer.com/ - EarthWeb)[email protected]


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Purple TechnologyPurple TechnologyJava Training and Consulting

All levels of courseshttp://www.purpletech.com/


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What is Java?

What is Java?

Largest island of the equatorial achipelago

of Indonesia

Famous for beaches and coffee

An island


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What is Java?

What is Java?

A programming language

Developed by Sun Microsystems

Open specification


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W

hat is Java?W

hat is Java?An architecture

Virtual Machine


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W

hat is Java?W

hat is Java?A platform

Libraries / APIs

Applications

Applets


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W

hat is Java?W

hat is Java?An Operating System (OS)

Tailored for NCs and Embedded Systems

Not an OS for PCs


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W

hat is Java?W

hat is Java?A really good buzzword

Coined by Kim Polese


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W

hy Java?W

hy Java?High Productivity

Low Cost

Run Anywhere

N-tier Applications


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W

here is Java?W

here is Java?Server-side programming

Enterprise computing

Distributed computing

Client-side multimedia


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W

here is Java heading?W

here is Java heading?Clients (Network, Distributed Computing

with Nodes)

Servers (Web servers, collaboration

services)

Embedded (TV Set-top, cell phones, smart

cards)


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F

acts andF

iguresF

acts andF

igures


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Numberof Java DevelopersNumberof Java Developers

(IDC)(IDC)


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R

ealR

eal--world Java Examplesworld Java Examples


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Andersen ConsultingAndersen Consulting60,000 employees who travel to client sites

VERY heterogeneous computing

environments

On-line travel system for their in-house

needs

Privileges according to employee status


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Andersen Consulting (cont.)Andersen Consulting (cont.)"Java is absolutely ready for prime time. It's

the most bulletproof language we've used.

We don't have to worry about memoryleaks. If we had done this in C, we would

still be debugging."

-Elmer Baldwin, President, via WorldNetwork.


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CSXrailway shippingCSXrailway shipping

Find out which train(s) have your freight on

map of USA

Click on train and see what freight belongs

to your company

Saving CSX $10M in next year


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CSXrailway shipping (cont.)CSXrailway shipping (cont.)

CSX, using Java, has halved the time to

write code and moved to a zero cost

software distribution model.

At the same time, CSX has moved to a

multi-client environment, improved

satisfaction, expanded reach and self-enabled the customer


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CSX (cont.)CSX (cont.)

"Java is CSX's enterprise computing solution Java

is deployed everywhere and at every level of CSX.

And we are working on architecturally purifyingCSX development," said Marshall Gibbs, assistant

VP of enterprise solutions at CSX Technology in

Jacksonville, FL, the IT unit of CSX Corp. "Our

ROI on projects where we use Java has increasedby 10 percent."


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Dun & BradstreetDun & Bradstreet

On-line office supply catalogue for in-house

use

Privileges according to status at company


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FederalExpressFederalExpress

"Java is our primary targeted application

platform for internal apps." says FedEx CIO

Dennis Jones. "No internal applicationwork is occurring for the client aside from

Java development."

Using Symantec Caf


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Ford MotorCredit Company.Ford MotorCredit Company.

"Ford Credit is using Java and the Internet

to better serve our customers. Ford Credit is

currently using Java to provide customers aconvenient way to access account

information - 24 hours a day, 7 days a

week." -Terry Bone, Ford Motor CreditCompany


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NationalLibrary of MedicineNationalLibrary of Medicine

(NIH)(NIH)Using Java for health and information

professionals to access database

Users' displays tailored to suit information

(instead of line-oriented displays)

"The development ofJava saved us the cost of

developing to platform-specific windowenvironments and greatly speeded up our

delivery of a working prototype version of

HSTAT (roughly six months from design to

delivery)."


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First Union Corp.First Union Corp.

"Java gives us greater selection of what

applications we can use. Well over 90% of

development is Java based," said MichaelLove, vice president of the smart card

initiative at First Union Corp in Charlotte,

NC.


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Java FoundationsJava Foundations


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What is a computer?What is a computer?

CPU

Memory

Input/output devices


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What is a programmingWhat is a programming

language?language?Set of instructions for computer

Stored in memory, executed by CPU

Grammar

Examples

Perl

C

C++

BASIC

LISP


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Lifecycle of a programLifecycle of a program

Source code

Compiler

Object code

Linker

Executable code


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What is a Script?What is a Script?

A script is a program, but not all programs

are scripts

Scripting Languages:

Lingo

Perl

JavaScript

TCL


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Script vs. ProgramScript vs. Program

Scripts are

smaller

easier learning curve

less scalable

number of developers per script is usually one

more task-specificusually tailored to a specific program or

function

fewer functions available


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Script vs. ProgramScript vs. Program

Programs are

usually larger

more powerful

more task-independent

more scalable

programs can have dozens of programmers

more code libraries

can produce their own graphical user interface


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Lifecycle of a scriptLifecycle of a script

Source code

Interpreter


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PerlPerl

Right on the line between scripting and

programming language

Possible to write large programs in Perl

Not a good idea

Many libraries available for Perl

Not very good GUI support

Contains compiler and interpreter


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Java CodeJava Code

Simple Object Oriented

Distributed Interpreted

Robust Safe

Secure Architecture Neutral

PortableH

igh PerformanceMulti-Threaded Dynamic (GC)


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Boy Scout CodeBoy Scout Code

trustworthy loyal

helpful friendly

courteous kind

obedient cheerful

thrifty braveclean reverent


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HistoryHistory

Green Project / FirstPerson / Oak

Consumer electronics

Set-top boxes

James Gosling, Patrick Naughton


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HistoryHistory

LiveOak (1993)

Arthur van Hoff

WebRunner (1994)

Patrick Naughton, Jonathan Payne

Java

Kim Polese


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HistoryHistory

Fall 1994: WebRunner written

Spring 1995: Java/HotJava announced at

SunWorld 95

Fall 1995: Java Day New York

Birth of Gamelan

Spring 1996: First JavaOne (San Francisco)


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What is an Operating System?What is an Operating System?

A program that runs other programs

Sits between programs and devices

Manages scheduling of concurrent

programs

Provides API to applications

Application Program Interface


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What is a Platform?What is a Platform?

Combination of OS, API, installed

programs, and hardware

Sometimes means one of those things,

sometimes means many


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Platform Independent: Why?Platform Independent: Why?

Write once, run anywhere

One code base to develop

Upwardly compatible with new technology

Writing code that will run on machines that

haven't been invented yet

Cross-compatible with existing installedbase

E.g. all the computers on the Web


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CrossCross--PlatformPlatform

Write-Once-Run-Anywhere

AIX, HP-UX, MacOS, OS2, Win95, WinNT,

Netware, UnixWare, Irix, Solaris, and others


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Platform Independent: How?Platform Independent: How?

Virtual Machine

Application Application Application

Windows MacOS Unix


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Java Class LifecycleJava Class Lifecycle

Source -> Bytecode -> Interpreter


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Java Class LifecycleJava Class Lifecycle

Source File

(.java)

Class File

(.class)

Compiler

(javac)

Java Virtual Machine (JVM)

ClassLoader

Bytecode Verifier

InterpreterJust-in-time

compiler

Security Manager

Operating System

Network

or

File System

= security gateway


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Security ArchitecureSecurity Architecure

Has to go through Verifier on one side and

Security Manager on the other

Sandbox

Cryptography / signed applets


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SecureSecure

Java:

Adjustable security: untrusted through levels

of trust

ActiveX:

Binary trust: all or nothing


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Java vs. ActiveXJava vs. ActiveX

Java ActiveX

File IO yes yes

Network IO yes yes

Applet Caching yes yes

Erase hard disk no yes

Upload confidential informationno yes


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ObjectObject--OrientedOriented

Encourages more flexible and reliable

designs

Fosters reuse of code and design

Reduces maintenance costs


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Automatic MemoryAutomatic Memory

ManagementManagementGreatly improves developer productivity

Reduces memory leakage problems


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Powers of tenPowers of ten

Cost of fixing problems

Design = $1

Development = $10

Debugging = $100

Deployment = $1000

Brooks, The Mythical Man MonthJava helps at early stages

Problems are caught early


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Distributed ComputingDistributed Computing

Applications reside where theyre needed

saving valuable desktop space

Accessible from any connected location

Native support for distributed app

development (java.net, RMI, CORBA,

DCOM)


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ServerServer--side strengthside strength

Built-in support for networking makes

development easy


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33--tierandntierandn--tierdevelopmenttierdevelopment

Flexible implementations separate user

interface from business logic and from

database storage


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ClientClient--side Javaside Java


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Copyright 1997 Alex Chaffee

ApplicationsApplications

Installed locally

Like any other application (Word, Photoshop)

Run as a local process

Can make network connections freely

No security restrictions

Still safety restrictions (e.g. cant write to

random memory)


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AppletsApplets

Live inside a browser

Stored as class files on a Web server

Are delivered through the internet or

intranet

On-demand, when needed

Run inside a Java-enabled web browser

Always downloads the latest version

Sometimes cached locally, but not reliably


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Applet SecurityApplet Security

Security restrictions

Are secure

Limited or no access to the local machine

(client)


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Applets (Diagram)Applets (Diagram)Browser Web Server

face.html

face.class

Here is my face:


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Client

Sockets andPorts (Diagram)Sockets andPorts (Diagram)

port 13

port 80

Time Service

Web Service

Socket

Server

Socket


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Applet as InputFormApplet as InputForm

Interactive

Verify input

Can send data to CGI or to custom server

More efficient use of client and server

resources


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Applet Security ModelApplet Security Model

a/k/a The Sandbox

Cant access local files

Cant launch local applications

Can only connect to applet host, i.e. the

host from which the applet itself was

downloaded

Cant accept connections, i.e. cant act as a

server


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Applet TagApplet Tag


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BrowserVirtualMachineBrowserVirtualMachine

Every browser has its own VM

Starts up either at launch or the first time

Java is needed

Starting Java...


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BrowsercompatibilityBrowsercompatibility

Every version ofJava is slightly different

Browsers, yuck

Navigator 2.x, 3.x, 4.x

Internet Explorer 3.x, 4.x

HotJava

We need...


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The ActivatorThe Activator


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Microsoft's JavaMicrosoft's Java


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Java vs. HTMLJava vs. HTML

HTML is a presentation format

Was never meant to be used for interactive

applications

Latency, or turn-around time, is too high

Dynamic HTML is really just window

dressing


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Java vs. HTMLJava vs. HTML

Java is a full-fledged application language

High-level of interaction with low-latency

More powerful and easier to use interfaces

Flexible enough to play any part in a

solution


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Java can do it allJava can do it all

Server-side or back-end processing

Middleware to transport and translate

information

Front-end user interface

Adapts to client: from PCs, NCs to Hand-

held devices


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Marimba CastanetMarimba Castanet

Marimba Castanet delivers applications

Changes nature of software

No more upgrades! Just automatic updates

http://www.marimba.com/

Founded by four original Java team

members


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Java vs. JavaScriptJava vs. JavaScript

Totally different technologies

JavaScript

Browser scripting language

Integrated with HTML page

Similar syntax


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Java and MultimediaJava and Multimedia


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Java and StreamingJava and Streaming

Streaming - starting to play a sound or

video before it has completely downloaded

A few streaming players written in Java

Flash

Shockwave


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Multimedia FAQMultimedia FAQ


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Is Java lowIs Java low--bandwidthbandwidth

friendly?friendly?Con:

Startup time

Need to load class files as well as media files

Pro:

Complete control over what media you

download at what timeClass files usually small

Is there an authoringIs there an authoring


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Is there an authoringIs there an authoring

environment to help youwriteenvironment to help youwrite

Java?Java?A few packages allow you to create

animations or ads and output class files

There are plenty of IDEs that require you towrite code

Many IDEs use Java Beans to make

programming more visual

How does one with noHow does one with no


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How does onewithnoHow does onewithno

programmingknowledgeprogrammingknowledge

oversee a Java basedproject?oversee a Java basedproject?


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What are some simpleuses ofWhat are some simpleuses of

Java on a Web site?Java on a Web site?Playing a sound

Displaying an animation

better to use GIF89

Interactive form

better to use JavaScript

Interactive banner ad

What's a good price to pay forWhat's a good price to pay for


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What s a goodprice to pay forWhat s a goodprice to pay for

a Java programmeryou aren'ta Java programmeryou aren't

sleepingwith?sleepingwith?

$50-$150 / hr


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Is Java good fordevelopingIs Java good fordeveloping

games?games?Sure, if you keep the window small

MPlayer

http://www.mplayer.com/java/games/


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WillJava be around 2 yearsWillJava be around 2 years

fromnow?fromnow?Absolutely


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Can you showme somekewlCan you showme somekewl

stuff done in Java?stuff done in Java?http://www.tdb.uu.se/~karl/brain.html

http://www.mplayer.com/java/games/

http://fragisland.fragzone.se


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ServerServer--side Javaside Java


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ServletsServlets

Cross-platform server-side scripting

Like CGI, only cooler


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Java Web ServerJava Web Server

Server written in Java

Runs servlets

Cheap


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Java Application ServerJava Application Server

Based on Java Web Server

High-performance

Enterprise Java Beans


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Enterprise Java BeansEnterprise Java Beans

Framework for enterprise servers

Adds transactions, persistence,

multithreading to server

Deals with tough issues, keeping server-side

business objects simple

Many EJB servers (IBM, Weblogic,JavaSoft, etc.)


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Java ComponentsJava Components


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Spaghetti CodeSpaghetti Code

Business logic mingled with systems code

Ported to legacy systems

Complex to developExpensive to maintain


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Java BeansJava Beans

Marketable software parts

Business applications as reusable

components

Leverages legacy systems

Easy to build/extend

Easy to distribute


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Copyright (c) 1997 Alex Chaffee

What is a component?What is a component?

Software part

Self-contained, independent

Plug-and-play, drag-and-drop Interact and interoperate with other

components

Assemble components to create anapplication

Ready for use by visual programming tools

Marketable


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Split DevelopmentSplit Development

JavaBeans producers

Create components for user-interface and

business-logicJavaBeans consumers

Use JavaScript Applet Embedding for web

pagesUse JavaStudio and other visual development

tools


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CommercialUserCommercialUser--InterfaceInterface

JavaBeansJavaBeansJScape (www.jscape.com)

KL Group (www.klg.com)

Lotus Kona project (www.lotus.com)

Rogue Wave

Dundas

Many more: see

http://www.javasoft.com/beans/


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Enterprise Java BeansEnterprise Java Beans

Adds business services to Java

Transactions, naming, etc.

Simplified development

dont need to worry about threading, locking,

transaction issues

IBM heavily involved


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Java MythsJava Myths


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Myth: Java is ProprietaryMyth: Java is Proprietary

Truly open standards

Developed in collaboration with other partners

IBM, Symantec, Intel, Oracle, Long period of public comment and revision

Several "clean-room" implementations underway

Kaffe

Sun does not compete with application developers

Or does it? (Java Application Server, HotSpot)

Java is an ISO Publically Available Standard

approved 20 to 2

M h J hM h J h


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Myth: Java has poorMyth: Java has poor

performanceperformanceVideo Games

Frag Island Quake Rendering Engine

(http://fragisland.fragzone.se/)Warp - Karl Hornell is God

(http://www.tdb.uu.se/~karl/java/warp.html)

Built-in Multi-threading improves

performance

M h J hM h J h


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performanceperformance Interpreter is fine for IO-bound apps

(including UI)

Very fast with Just-in-time (JIT) compilersNow available on most platforms

HotSpot

Object-oriented optimizationGenerational Garbage Collection

malloc/free test: JVM 18 sec, MSJVM 8 sec, C++ 6

sec, HotSpot 2 sec.

Many other enhancements

M h J hM h J h


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performanceperformanceCompile to native code where possible

Compile server-side applications directly to

the platform on which theyll be used

SuperCede and Symantec Caf/Visual Caf

support this

Note: lose some benefits ofJava (notablydynamic linking)


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Myth: Java is immatureMyth: Java is immature

Compiler Bugs

Almost none in real-world experience

Java Compatibility Test required by all JavaVMlicensees


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Class Library Bugs

AWT in JDK 1.1 much improved

JFC takes Java UI to the next level


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Java Virtual Machine problems

Most are from implementations in browsers

They lag behind JDK releasesAffects cross-platform compatibility

100% Pure Java crusade, run seamlessly across

platforms

Activator

M th W itM th W it


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Myth: Write once,runMyth: Write once,run

anywhereanywhereShould be, Write once, debug everywhere,

run anywhere

Need a good debugger (like Caf)


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Java Myths: NCs vs. PCsJava Myths: NCs vs. PCs

PC vs NC: reality both will co-exist and

overlap in functionality

Network and server load issues: realitycareful system administration and caching

required

Don't need to throw everything away andstart from scratch


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Myth: Java vs. MicrosoftMyth: Java vs. Microsoft

Java works great under Microsoft OS

IIS has full Java integration for ASPs


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Java Libraries and APIsJava Libraries and APIs

Java API StrategyJava API Strategy


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Java API StrategyJava API Strategy


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Core Libraries (APIs)Core Libraries (APIs)

UI

JFC

IO

Net

JDBC

RMI


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Extended APIsExtended APIs

Electronic Commerce

Network Management

Security

JavaBeans - GUI Components

Enterprise Java - Enterprise Wide Backend Database

Connectivity

Server - Web Server or Distributed Applications

JavaMedia - Multimedia


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UserInterface: AWTUserInterface: AWT

Based on native widgets

Native look-and-feel

Simple components


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Swing/JFCSwing/JFC

Builds on AWT and IFC

Pluggable look and feel

Rich set of pre-defined components

Fully customizable

Simplify commercial GUI development

Open component market


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Swing GUISwing GUI


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AFC /WFCAFC /WFC

Microsoft's alternative

Write once, run on Windows

Out as of March 11, 1998


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Standard ExtensionsStandard Extensions

Servlets

InfoBus

Java Help

JavaMail


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Java and BusinessJava and Business

JDBC

JNDI (Java Naming and Directory

Interface)Java Transaction Services



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Distributed ComputingDistributed Computing


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java.netjava.net

uses TCP/IP

works on all Java platforms

all open protocols of the Internet

HTTP, FTP, SMTP, IMAP

Source code:

Socket s = new Socket(www.internet.com,80);


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OtherNetworkTechnologiesOtherNetworkTechnologies

RMI

CORBA

JDBC

Other JavaOther Java


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OtherJavaOtherJava

Initiatives/EnvironmentsInitiatives/Environments


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JavaPCJavaPC

Turn old PCs into NCs


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PersonalJavaPersonalJava

Tailored for products such as mobile

phones, set top boxes, screenphones, mid-

range mobile phonesDesigned to fit in devices with 2 Mb or less


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Embedded JavaEmbedded Java

tailored for small memory, high volume

products

Tailored for products such as industrialcontrollers, pagers, routers, switches

Designed to fit in devices < .5 Mb ROM

Doesn't require general purpose appletdownloading capabilities

Includes the Java VM and core set of APIs


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Java CardJava Card

Use in Smart Cards

Java Ring

Dallas Semiconductor

32K program RAM, 6K data RAM

Serial port interface

Contains private key cryptoRuns off the 1 bits

Auto-zeroing RAM


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OtherCompaniesOtherCompanies


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NetscapeNetscape

First Java licensee

Recently announced they're canceling their

Java programJava will still work in Netscape with

Activator etc.

Also working (halfheartedly) on Javagator


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MicrosoftMicrosoft

COM integration

IIS

AFC / WFC

Visual J++ 6.0

SDKJ 3.0 just released in beta

Write once, run on Windows

Did someone say lawsuit?


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SymantecSymantec

First with first out with dev tools, an IDE, a

RAD IDE, a JIT, and a database-oriented

productDeveloping JFC core technologies

Developing JFC look-and-feels

Just-in-time compiler keeps getting betterEnhancing debugger support


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IBMIBM

VisualAge forJava - nice RAD tool

San Francisco


Licensing picoJava


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Developing JavaDeveloping Java

ll


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Developing Java:IDEsDeveloping Java:IDEs

Best ones are on PC

Symantec Caf

Borland JBuilder

Microsoft Visual J++

l S dl S d


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Developing Java: Java StudioDeveloping Java: Java Studio

C lC l


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ConclusionConclusion


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[APPLAUSE]


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[DINNER]

R l W b Si RR l W b Si R


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RelevantWeb SiteResourcesRelevantWeb SiteResources

Javasoft & Sun: www.javasoft.com &

www.sun.com

Developer.com: java.developer.comSymantec: www.symantec.com

IBM: www.ibm.com/java

Borland: www.borland.com

SuperCede: www.supercede.com

Purple Tech: www.purpletech.com

C diC di


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CreditsCredits Purple Technology

Java Training and Consulting

Symantec Corp.

J

ava Development Tools Advanced Web Technologies

Java-only training, mentoring, and consulting company

Sun Microsystems

JavaOne presentations: Lew Tucker, Alan Baratz,James Gosling

Personal Thanks

Lew Tucker, Gerry Seidman, Ian McFarland

A di N ki B iA di N ki B i


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Appendix: Networking BasicsAppendix: Networking Basics

N t ki B iN t ki B i


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Networking BasicsNetworking Basics

TCP/IP vocabulary and concepts

WWW vocabulary and concept

T l t A li tiT l t A li ti


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Telnet ApplicationTelnet Application

Demo of time service (port 13)

Demo of login service (port 23)

Demo ofHTTP service (port 80)

A N t k IA N t k I


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A NetworkIs...A NetworkIs...

node

any device on the network

hosta computer on the network

address

computer-readable name for hosthost name

human-readable name for host

A N t k DA N t k D


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A NetworkDoes...A NetworkDoes...

datagram (or packet)

little bundle of information

sent from one node to anotherprotocol

roles, vocabulary, rules for communication

IPthe Internet Protocol

TCP/IP Th I t t P t lTCP/IP Th I t t P t l


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TCP/IP: The InternetProtocolTCP/IP: The InternetProtocol

Physical Network

Transport Layer (TCP, UDP)

Internet Layer (IP)

Application Layer (HTTP, FTP, SMTP)

TCP/UDP/IPTCP/UDP/IP


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TCP/UDP/IPTCP/UDP/IP IP

raw packets

the Internet Layer

TCP

data stream

reliable, ordered

the Transport Layer

UDP user datagrams (packets)

unreliable, unordered

the Transport Layer

Th Th ITh Th I


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The Three I sThe Three I s

internet

any IP-based network

Internetthe big, famous, world-wide IP network

intranet

a corporate LAN-based IP networkextranet

accessing corporate data across the Internet

IP AddressesIP Addresses


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IPAddressesIPAddresses

IP Address: identifies a host

4 bytes = 2^32 = 4,294,967,296

DNS: converts host names / domain namesinto IP#s

IPv6IPv6


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IPv6IPv6

aka IP: the Next Generation

16-byte addresses

2^128 =340,282,366,920,938,460,000,000,000,000,

000,000,000

No Y2K problem: InetAddress Class hidesimplementation

Sockets and PortsSockets and Ports


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Sockets andPortsSockets andPorts

Port: a meeting place on a host

one service per port

1-1023 = well-known services1024+ = experimental services, temporary

Socket: a two-way connection

Sockets and Ports (Diagram)Sockets and Ports (Diagram)


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Client

Sockets andPorts (Diagram)Sockets andPorts (Diagram)

port 13

port 80

Time Service

Web Service

Socket

Server

Socket

WellWell Known PortsKnown Ports


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WellWell--KnownPortsKnownPorts

20,21: FTP

23: telnet

25: SMTP43: whois

80: HTTP

119: NNTP

1099: RMI

TheWorld WideWebTheWorld WideWeb


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TheWorldWideWebTheWorldWideWeb

Runs on the Internet

Uses HTTP protocol

Invented by Tim Berners-Lee (and a cast ofthousands)

URLURL


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URLURL

protocol://host[:port][/path/][file][#anchor]

http://www.javasoft.com/sfaq/index.html

http://www.javasoft.com/sfaq/ ftp://ftp.stinky.com/pub/java/course.zip

HTTPHTTP


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HTTPHTTP

port 80 default

Client:GETpath HTTP/1.0

Header: valueblank line

Server:HTTP/1.0 OK 200

Header: valueblank line

data

telnet demo again

HTMLHTML


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HTMLHTML

Text file

Tags - markup commands embedded in

texte.g.

This is bold and this is

italics

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