Introduction to Java

JAVA PROGRAMMING

         Java is a general purpose, complete object-oriented language, developed by Sun Microsystem of USA in 1995.

            Initially, it was called as “Oak” by “James Gosling”, one of the inverters of the language. Java was designed for the development of software for consumer electronic devices like TVs, VCRS toasters and such other electronic machines.

            The Java team which included Patrick Naughton discovered that the existing language like C and C++ had limitations in terms of both reliability and portability. So, they modelled their new language Java on C & C++ but removed a numbers of features of C & C++. Thus, Java has been introduced as simple, reliable, portable and powerful language.

The following table shows the development Phase of Java:-

YEAR	DEVELOPMENT
1990	Sun Microsystem decided to develop this software for electronic devices. The team of programmers head by James Gasling.
1991	After exploring the feature of C++, the team announced a new language named “OAK”.
1992	Sun Microsystem demonstrated this language as a “Green Project” on home appliances devices.
1993	This language was established the compatibility with Internet.
1994	The team developed a web browser called “HotJava” to locate and run applet programs on Internet.
1995	Oak was renamed as “Java”. Java is just a name and is not an acronym.
1996	Java established itself not only a leader for internet programming but also a complete OOPS language.

INTRODUCTION TO JAVA

Java is a complete object-oriented language. Which is developed by Sun Microsystem in 1995. The popular developers of Java was James Gosling and Patrick Naughton.

           It is called fully OOPS language because no any programs can be done without the use of class and object. Even the main( ) method of Java also reside within a class.

          Thus, we can say that Java does not support the concept of Global functions. At least, one class must be used in every program of Java. That’s why, it is known as fully Object-Oriented language (OOPS).

JAVA Vs C++

Java is differ from C++ in several ways, which are as follows:-

1.  There are no header file in Java.
2.  Java does not use pointers.
3.  Java does not support global variables and methods. Every variable and method is declared   within a Class and forms part of that Class.
4.  Java does not support operator – overloading.
5.  Java does not have template Classes as in C++.
6.  Java does not support multiple inheritance of Classes. It is accomplished using a new feature   called “Interface”.
7.  Java has both translators (Compiler and Interpreter). Whereas C++ has only one translator   (Compiler).
8.  Java has no own editor whereas C++ has own.
9.  Java is architecture independent language.
10.  Java is neither a superset nor a subset of C/C++.

JAVA AND INTERNET

Java is strongly associated with the Internet because of the fact that the first application program written in Java was HotJava, a web browser to run applets on Internet. Internet users can use Java to create applet programs and run them locally using a “Java-enabled browser” such as HotJava.

           It is also used a Java-enabled browser to download an applet located on a computer anywhere in the internet and run it on his local computer.

           Internet users can also set up their websites containing Java applets that could be used by other remote users of Internet. So, we can say that, Java is popularly known as Internet language.

JAVA SUPPORT SYSTEM

We are perform the operation of Java and Java-enabled browsers on the Internet requires a variety of support System. There are following the system necessary to support Java for delivering information on the Internet –

JAVA SUPPORT SYSTEM	DESCRIPTION
Internet Connection	Local computer should be connected to the Internet.
Web Server	A program that accepts request for information and sends the required document.
Web Browser	A program that provides access to WWW and runs Java applets.
HTML	A language for creating hypertext for the web.
APPLET Tag	For placing Java applets in HTML document.
Java Code	Java code is used for defining Java applets.
ByteCode	Compiled Java Code that is referred to in the APPLET tag and transferred to the user computer.