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QuickStart Java
Learning to Program in Java
Dr. Tom Way
October 21, 2005
Applied Computing Technology Laboratory
The Java Programming Language
Developed in 1996
 Created by Patrick Naughton, James
Gosling and Mike Sheridan (and others)
at Sun Microsystems
 Original called the “Green Project”
 Uses Object-Oriented paradigm
 Good for general purpose applications,
web apps, databases, etc.

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Java Advantages
Platform independence – “write once,
run anywhere”
 Fast prototyping of user interfaces
 Excellent documentation
 Great for teaching and learning
 Increasing in popularity
 Now used widely in industry
 Automatic garbage collection

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Java Disadvantages
Compile to Java byte code, not native
 Runs on “virtual machine,” so can be
slower than native machine
 Doesn’t have true multiple inheritance
(but can get through multiple interfaces)
 Some simple things are harder –
keyboard input, primitive types vs.
Objects

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Java Specification

Third edition available on Sun web site
http://java.sun.com
 Explains:






Grammar
Lexical structure
Types, values, variables
Type conversions and promotions
Packages, classes, interfaces, inheritance
Arrays, exceptions, execution, blocks, statements,
expressions, assignments, threads, locks
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Java Grammar

Available on Sun web site

http://java.sun.com/docs/books/jls/third_edition/html/syntax.html#18.1
Example:
Type:
Identifier [TypeArguments]{ . Identifier [TypeArguments]} {[]}
BasicType
TypeArguments:
< TypeArgument {, TypeArgument} >
TypeArgument:
Type ? [( extends | super ) Type]
Identifier:
IDENTIFIER
BasicType:
byte | short | char | int | long | float | double | boolean
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Identifier
Identifier:
IdentifierChars but not a Keyword or
BooleanLiteral or NullLiteral
IdentifierChars:
JavaLetter IdentifierChars JavaLetterOrDigit
JavaLetter:
any Unicode character that is a Java letter
JavaLetterOrDigit:
any Unicode character that is a Java letter-ordigit
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Step 1: Getting Started

Download & install JDK from:
http://java.sun.com/j2se/1.5.0/download.jsp
Double-click on file to run installer
 Follow your nose
 Check online installation instructions for
helpful tips

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Step 2: Eclipse

Download & install Eclipse from:
http://eclipse.org/downloads
Unzip to a directory (e.g., C:\eclipse)
 Create desktop shortcut, if you like

Right-click on eclipse.exe
 Send to -> Desktop (create shortcut)

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Step 3: Write a simple program
File->New->Project
 Select “Java Project”
 Name project “Hello World”
 Select File->New->Class
 Name the class “HelloWorld” (no spaces)
 Check “public static void main()” box
 Add one line in the main() method:

System.out.println(“Hello world!”);
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Step 4: Run the program
Right-click on HelloWorld.java
 Select Run As->Java Application
 Watch console at bottom for output
 Congratulations!

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Learning more about Java

Visit the QuickStart Languages web site
http://actlab.csc.villanova.edu/quickstart

View or download the Java API:
http://java.sun.com/j2se/1.5.0/docs/api/index.html

Read the Java Developers Almanac
http://javaalmanac.com/

Google search for: java program examples
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