Java Programming Assignment

KhaledMaarof
ch1Object-OrientedProgramming.ppt

Object-Oriented
Programming

Object-Oriented Programming

An algorithm is a step-by-step process.

A computer program is a step-by-step set of instructions for a computer.

Every computer program is an algorithm.

Algorithms have a long history in science, technology, engineering and math.

Object-Oriented Programming

Early computers were
far less complex than computers are today.

Their memories were smaller and their programs were much simpler.

Object-Oriented Programming

They usually executed only one program at a time.

Object-Oriented Programming

Modern computers are smaller, but far more complex than early computers.

The can execute many programs at the same time.

Object-Oriented Programming

Computer scientists have introduced the notion of objects and object-oriented programming to help manage the growing complexity of modern computers.

Object-Oriented Programming

An object is anything that can be represented by data in a computer’s memory and manipulated by a computer program.

Object-Oriented Programming

An object is anything that can be represented by data in a computer’s memory and manipulated by a computer program.

Numbers

Object-Oriented Programming

An object is anything that can be represented by data in a computer’s memory and manipulated by a computer program.

Text

Object-Oriented Programming

An object is anything that can be represented by data in a computer’s memory and manipulated by a computer program.

Pictures

Object-Oriented Programming

An object is anything that can be represented by data in a computer’s memory and manipulated by a computer program.

Sound

Object-Oriented Programming

An object is anything that can be represented by data in a computer’s memory and manipulated by a computer program.

Video

Object-Oriented Programming

An object is anything that can be represented by data.

Object-Oriented Programming

An object can be something in the physical world or even just an abstract idea.

An airplane, for example, is a physical object that can be manipulated by a computer.

Object-Oriented Programming

An object can be something in the physical world or even just an abstract idea.

A bank transaction is an example of an object that
is not physical.

Object-Oriented Programming

To a computer, an object is simply something that can be represented by data in the computer’s memory and manipulated by computer programs.

Object-Oriented Programming

The data that represent the object are organized into a set of properties.

The values stored in an object’s properties at any one time form the state
of an object.

Name: PA 3794

Owner: US Airlines

Location: 39 52′ 06″ N  75 13′ 52″ W

Heading: 271°

Altitude: 19 m

AirSpeed: 0

Make: Boeing

Model: 737

Weight: 32,820 kg

Object-Oriented Programming

Computer programs implement algorithms that manipulate the data.

In object-oriented programming, the programs that manipulate the properties of an object are the object’s methods.

Object-Oriented Programming

We can think of an object as a collection of properties and the methods that are used to manipulate those properties.

Properties

Methods

Object-Oriented Programming

A class is a group of objects with the same properties and the same methods.

Object-Oriented Programming

Each copy of an object from a particular class is called an instance of the object.

Object-Oriented Programming

The act of creating a new instance of an object is called instantiation.

Object-Oriented Programming

A class can be thought of as a blueprint for instances of an object.

Object-Oriented Programming

Two different instances of the same class will have the same properties, but different values stored in those properties.

Object-Oriented Programming

The same terminology is used in most object-oriented programming languages.

Object

Instance

Property

Method

Instantiation

Class

State