This document introduces Java programming and provides an overview of key concepts. It explains that Java is an object-oriented programming language that runs on any machine with a Java Virtual Machine installed. The document also describes what a computer is, the structure of Java code including classes, methods and statements, and how Java code is compiled and run. It emphasizes that everything in Java is an object and discusses inheritance and common methods.

1. Welcome
To
Introduction to
Java
Programming

2. Meet Your Instructor
That’s me

3. Who Should Drink JAVA?
Have you done some programming?
Do you want to learn Java?
Do you prefer stimulating dinner conversations
over coffee to dry, dull, technical lectures?
Do you need this course to graduate?
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4. Who Drinks JAVA?
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5. What Is A Computer?
A computer is something that takes in information
(input), processes it according to a set of
instructions (program), and produces a result
(output).
Computers communicate through a binary
alphabet. The letters in this alphabet are ‘0’ and
‘1’. Everything else is made out of these ‘letters’
which are called bits.
Bits are represented in a computer by electrical
signals: low voltage would mean a ‘0’ and higher
voltage a ‘1’. Eight bits gathered together form
one byte.
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6. What Is JAVA?
Java is a free, open-source, Object Oriented
Programming (OOP) language – everything is
contained inside classes and objects.
Java is über portable – it can run on any
machine with a Java Virtual Machine (JVM)
installed.
No matter what computer you have, you can
write the same Java programs.
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7. How WE use Java
Sourc
e
Code
Compiler
Java
bytecod
e
V
i
r
t
u
a
l
M
a
c
h
i
n
e
s

8. How WE use Java
Source Code
Compiler
Virtual Machines
Java bytecode
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9. Code Structure in Java
source
code
class
file
method
1statement
method
2statement
statement

10. What goes in the source
file?
A source file (with the .java extension)
holds one class definition. The class
represents a piece of your program,
although a very tiny application might
need just a single class. The class must
go within a pair of
curly braces
public class Bicycle {
}
clas
s
The source file MUST have the same
name as the class. For example, the
Bicycle class my be stored in the
Bicycle.java file.
A class is the blueprint from
which individual objects are
created. Think of a bicycle…

11. What goes in a class?
A class has one or more methods. In
the Bicycle class, the pedal method will
hold instructions for how the Bicycle
should pedal. Your methods must be
declared inside a class (in other words,
within the
curly braces
public class Bicycle{
void pedal( ) {
}
}
metho
d
of the class).
A bicycle might have some
methods such as: speedup(),
break(), gear(), direction()…

12. What goes in a method?
Within the
curly braces public class Dog {
void bark ( ) {
statement1;
statement2;
statement3;
}
}
statemen
ts
of a method, write your instructions for
how that method should be performed.
Method code is basically a set of
statements, and for now you can think
of a function or procedure.
Bicycle{
pedal( ) {
statement1;
statement2;
statement3;
What are you
staring at?

13. One Blueprint Can Be Used To
Help Build Different
Objects
Shape
rotate ( )
playSound
( )
Squar
e Triangl
e
Circle
Amoeba
This is called
inheritance

14. EVERYTHING
is made from OBJECTS
Object
equals()
getClass()
hashCode()
toString()
Shape
rotate()
playSound()
Circle
doSomething()
This is the Object class
from which ALL other
objects are created.

15. What You Will Get Out Of
Learning and Using JAVA!
A thorough understanding of Object Oriented
Programming.
Learn a language that can be run on any platform.
Build your programming skills and confidence.
Learn how to work and program in groups.
Develop Graphical User Interfaces.
If you can make it through the day
without programming, you haven’t tried
JAVA!

16. Where To Start
Setup Eclipse Classic 3.6
Write your first Java program