Topics

Programming Language Object Oriented Programming JAVA – An Introduction JAVA Milestones JAVA Features

Programming Languages

What is Program:A program is like a recipe. It contains a list of ingredients (called variables) and a list

of directions (called statements) that tell the computer what to do with the variables. The variables can represent numeric data, text, or graphical images.

Types of Languages:Machine Language:

“Natural Language” of computer component. Machine dependent.

Assembly Language: English – like Abbreviations represent computer operations. Translator program (assemblers) convert to machine language.

High-level language: Allows for writing more “English-like” instructions Contains commonly used

mathematical operations. Compiler / Interpreter converts to machine language. C, C++, JAVA, VB, PASCAL, FORTRAN, COBOL, PYTHON, C# etc.,

Object Oriented Programming

OOP treats data as a critical element in the program development and does not allow it to flow freely around the system.

It ties data more closely to the functions that operate on it and protect it from unintentional modification by other functions.

OOP allows us to decompose a problem into a number of entities called objects.

Some of features of Object Oriented Programming:

Emphasis is on data rather than procedure or function. Programs are divided into what are know as objects. Data is hidden and cannot be accessed by external functions Objects may communicate with each other through methods.

Object Oriented Programming

Basic Concepts of Object Oriented Programming: Classes and Objects

Data Abstraction and Encapsulation – The wrapping up of data and methods into a single unit is know as encapsulation. Abstraction refers to the act of representing essential features without including the background details or explanations.

Inheritance – Inheritance is the process by which objects of one class acquire the properties of objects of another class.

Polymorphism – Polymorphism means ability to take more than one form.

Dynamic Binding – Dynamic binding means that the code associated with a given procedure call is not known until the time of the call at runtime.

Message communication – The concept of message passing makes it easier to talk about building systems that directly model or simulate their real world.

JAVA – An Introduction

Java - The new programming language developed by Sun Microsystems in 1991.

Originally called Oak by James Gosling, one of the inventors of the Java Language.

Java Authors: James , Arthur Van , and others.

Originally created for consumer electronics (TV, VCR, Freeze, Washing Machine, Mobile Phone).

Java - CPU Independent language

Internet and Web was just emerging, so Sun turned it into a language of Internet Programming.

It allows you to publish a webpage with Java code in it.

JAVA – Milestones

Year Development

1990 Sun decided to developed special software that could be used for electronic devices. A project called Green Project created and head by James Gosling.

1991 Explored possibility of using C++, with some updates announced a new language named “Oak”

1992 The team demonstrated the application of their new language to control a list of home appliances using a hand held device.

1993 The World Wide Web appeared on the Internet and transformed the text-based interface to a graphical rich environment. The team developed Web applets (time programs) that could run on all types of computers connected to the Internet.

JAVA – Milestones

Year Development

1994 The team developed a new Web browsed called “Hot Java” to locate and run Applets. Hot-Java gained instance success.

1995 Oak was renamed to Java, as it did not survive “legal” registration. Many companies such as Netscape and Microsoft announced their support for Java

1996 Java established itself it self as both 1. “the language for Internet programming” 2. a general purpose OO language. Sun released JDK 1.0

1997 JDK 1.1

1998 Sun released the Java 2 with version 1.2 of Software Development Kit (SDK 1.2)

1999 2 platforms were released J2SE, J2EE

2000 and 2002

SDK 1.3 and SDK 1.4

2004 J2SE with JDK 5.0 was released. This is know as J2SE 5.0

JAVA – Features

Simple

Object-Oriented

Compiled and Interpreted Portable

JAVA – Features

Simple

Object-Oriented

Compiled and Interpreted

Portable

Java is partially modeled on C++, but greatly simplified and improved. Some people refer to Java as "C++--" because it is like C++ but with more functionality and fewer negative aspects.

Java is inherently object-oriented. One of the central issues in software development is how to reuse the code. Object-oriented programming provides great flexibility, clarity, and reusability through encapsulation, inheritance, and polymorphism.

JAVA – Features

Simple

Object-Oriented

Compiled and Interpreted Portable

JAVA – Features

Simple Object-Oriented

Compiled and Interpreted

Portable Converts the source to the object code.

JAVA – Features

Simple

Object-Oriented

Compiled and Interpreted

Portable

Java programs are portable. They can be run on any platform without being recompiled.

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