Learn JAVA from the beginning.(Chapter 1)

                                                   

Learn java from the beginning is an article series to teach you JAVA programming language from the beginning. In this article series I hope to teach you not only programming side of java but also very important theoretical parts in java language. My first article will help you to get a good start to learn java. Let’s start with a brief history of java.

In 1991 James Gosling and his team from Sun Micro-systems made the foundation to develop java language.  They aimed to design a platform independent programming language to program home appliances which are controlled by a wide variety of computer processors. Originally this language is called “Oak” and in 1995 its name changed to “Java”. There was a very beautiful story goes with name “Java”. The developing team of this language want to register this language with the name “Oak”. When it was discovered there was already existed another programming language with same name. Therefore developers had a big trouble. Meanwhile they visited to a coffee shop to have a cup of coffee. They love the taste of the coffee came from java and named the language with the name “Java”.

Java has become the most popular and predominant language of the current age. It is

•          A full-fledged application programming language. 
•         It has additional capability as a web programming language.
•          A pure Object Oriented language.
•          Adopts its look from C++ and behavior from Small-talk.
•          Simple, secure, portable and robust language.
•          Platform neutral language.

A Java program is mostly a collection of objects talking to other objects by invoking

Each other's methods. Every object is of a certain type, and that type is defined by a class or an interface. Most Java programs use a collection of objects of many different types.

There are some important terms you should know at the beginning. Let’s see what they are.

Class

Class is a collection of data and methods that operate on that data.

Method

Method is a group of statements in a class that handle a task.

Package

Package is a group of logically related codes.

Java Byte-code

A set of instructions that look like machine code but are not specific to any processor. This is generated by java compiler. This can be get as machine language for java Virtual Machine. It is easy to translate to machine language of various kind of computers. This is executed by java interpreter and this is invisible to programmer.

Java virtual machine

The Virtual Machine is a program that processes all your code correctly.  So you need to install it before you can run any Java code.

Source program

This is the one that you write in java language and that always has a file extension of .java.

Object program

This is the binary byte code program generated by the java compiler which always has file extension of .class.

Stay tuned…In next article I will teach you how a java program works.