This document provides an overview of the Java programming language, including its history, key characteristics, and uses. It describes how Java was created in the 1990s to be a portable, platform-independent language for developing applications on the internet (World Wide Web) and other networks. The document outlines Java's main features, such as being object-oriented, interpreted, robust, secure, distributed, and architecture neutral, which allow programs written in Java to "write once run anywhere" on different operating systems and hardware.
2. CONTENTS
1. Introduction about Java….
2. Why Java is Important….
3. What is Java….
4. Characteristics of Java….
5. Java Environment….
6. JDK Evolutions….
7. Java Editions….
8. Java is architecture-neutral….
9. WORA(Write Once Run Anywhere)….
3. Java is a Programming Language.
It was Originally developed by Sun Microsystem.
It was interacted by James Gosling.
James Gosling was unhappy using c++ programming
language so he developed Java.
They developed a platform independent software based on the power of
networks that can run on different application areas, such as computers
and electronic devices.
It was initially called 'Oak‘.
It was renamed as 'JAVA' released in 1995 as a core component of Sun
Microsystems Java platform.
James Gosling
4. WHY JAVA IS IMPORTANT
1. Trouble with C/C++ language is that they are not portable and are not
platform independent languages.
2. Emergence of World Wide Web, which demanded portable programs
5. WHAT IS JAVA
A general-purpose object-oriented language.
Write Once Run Anywhere (WORA).
Designed for easy Web/Internet applications.
Widespread acceptance.
6. CHARACTERISTICS OF JAVA
Java is simple & Familiar.
Java is object-oriented.
Java is distributed.
Java is interpreted.
Java is robust.
Java is architecture-neutral.
Java is portable.
Java’s performance.
Java is multithreaded.
Java is dynamic.
Java is secure.
7. JAVA IS SIMPLE & FAMILIAR
Java was designed to be simple and familiar to learn language.
Fundamental concepts can be grasped quickly as the features borrowed
from C & C++.
Features were removed that led to poor programming practices or were
rarely used.
It does not use pointers, goto statement, Preprocessor header files etc.
8. JAVA IS OBJECT-ORIENTED
All coding and data reside within object and classes.
Java has built-In exception handling.
Everything in Java (except the primitive data types) is an object.
The object model in java is simple and easy to extend so that complex
programming problems can be reduced to simple solutions.
Extensive set of classes, arranged in packages.
e.g. java.awt, java.io, java.net .
9. JAVA IS INTERPRETED
Java is both a compiled and Interpreted language.
Java Compiler generates platform-independent byte codes that are
interpreted into machine readable instructions by a Java Virtual Machine
(Java Interpreter) at runtime.
10. JAVA IS PORTABLE
Java programs are designed to work in a networked environment on a
variety of computers and operating systems.
The size of the primitive data types are machine independent.
Compiler generates platform independent byte codes rather than
native machine code, so it can be implemented on any machine.
11. JAVA IS ROBUST
Java has hard-and-fast rules for compile-time and runtime error
checking.
Java supports automatic garbage collection so all memory
corruptions or unauthorized memory accesses are impossible.
Many error-prone features of C/C++ programming were removed.
12. JAVA IS SECURE
Usage in networked environment requires more security.
JVM verifies all byte codes before execution & ensures all programs
follow the rules regarding object access and usage.
Java ensures that program cannot gain access to memory locations
without proper authorization.
13. JAVA IS DISTRIBUTED
Java is network friendly.
Java is designed as a distributed language for creating applications on
networks.
Multiple programmers can work together on a single project from
multiple remote locations.
Both data and programs can be shared on networks.
14. JAVA IS MULTITHREADED
This feature allows us to handle multiple tasks simultaneously.
Designed to run multiple threads.
Easy to implement.
Other systems have provided facilities via light weight libraries, but Java
has in-built language support.
Great for multimedia displays.
15. JAVA IS DYNAMIC.
Provides a highly dynamic runtime environment.
Allows dynamically linking in new class libraries, methods and objects.
New code can be linked on demand from anywhere on the network and
new types can be created as needed dynamically.
16. JAVA ENVIRONMENT
Java includes many development tools, classes and methods
Development tools are part of Java Development Kit (JDK) and
The classes and methods are part of Java Standard Library (JSL), also known as
Application Programming Interface (API).
JDK constitutes of tools like java compiler, java interpreter and many.
API includes hundreds of classes and methods grouped into several
packages according to their functionality.
18. JAVA EDITIONS
J2SE (Java 2 Standard Edition) - to develop client-side standalone
applications or applets.
J2ME (Java 2 Micro Edition ) - to develop applications for mobile devices
such as cell phones.
J2EE (Java 2 Enterprise Edition ) - to develop server-side applications
such as Java servlets and Java Server Pages.