Java is a high level programming Language. It was introduced by “SUN MicroSystems” in June 1995. It was officially released in November 1995. It was developed by a team under James Gosling.
Its original name was “OAK” meant for consumer electronic devices and later renamed to Java. Java has become the standard for Internet applications. It provides interactive processing and easy use of graphics and animation on the Internet. Since the Internet consists of different types of computers and operating systems.
A common lang. needed to enable computers. To run prgs that run on multiple plot forms. This need was fulfilled by Java, and it so on. Because the lang.of choice for the Internet. Java is Object-Oriented lang.built on C and C++. It derives its syntax from C and its Object-Oriented features are influenced by C++.
Java can be used to create two types of prgs. Those are Applications and Applets.
An application is a prg.that runs on the user’s computers under the
operating system. An Applet is a small window based prg.that runs on
HTML page using a java enabled web browser like internet Explorer,
Netscape Navigator or an Applet Viewer.
Java Features : Here we list the basic features that make Java a powerful and popular programming language :
1)Compiled and Interpreter:-
has both Compiled and Interpreter Feature Program of java is First
Compiled and Then it is must to Interpret it .First of all The Program
of java is Compiled then after Compilation it creates Bytes Codes rather
than Machine Language. Then After Bytes Codes are Converted into the
Machine Language is Converted into the Machine Language with the help of
the Interpreter. So For Executing the java Program First of all it is
necessary to Compile it then it must be Interpreter
2)Platform Independent:-
Java Language is Platform Independent means program of java is Easily
transferable because after Compilation of java program bytes code will
be created then we have to just transfer the Code of Byte Code to
another Computer This is not necessary for computers having same
Operating System in which the code of the java is Created and Executed
After Compilation of the Java Program We easily Convert the Program of
the java top the another Computer for Execution
3)Object-Oriented:-
We Know that is purely OOP Language that is all the Code of the java
Language is Written into the classes and Objects So For This feature
java is Most Popular Language because it also Supports Code Reusability,
Maintainability etc.
4)Robust and Secure:-
The Code of java is Robust andMeans ot first checks the reliability of
the code before Execution When We trying to Convert the Higher data type
into the Lower Then it Checks the Demotion of the Code the It Will
Warns a User to Not to do this So it is called as Robust
Secure :
When We convert the Code from One Machine to Another the First Check
the Code either it is Effected by the Virus or not or it Checks the
Safety of the Code if code contains the Virus then it will never
Executed that code on to the Machine.
5)Distributed:-
Java is Distributed Language Means because the program of java is
compiled onto one machine can be easily transferred to machine and
Executes them on another machine because facility of Bytes Codes So java
is Specially designed For Internet Users which uses the Remote
Computers For Executing their Programs on local machine after
transferring the Programs from Remote Computers or either from the
internet.
6)Simple Small and Familiar:-
is a simple Language Because it contains many features of other
Languages like c and C++ and Java Removes Complexity because it doesn’t
use pointers, Storage Classes and Go to Statements and java Doesn’t
support Multiple Inheritance.
7)Multithreaded and Interactive:-
Java uses Multithreaded Techniques For Execution Means Like in other in
Structure Languages Code is Divided into the Small Parts Like These
Code of java is divided into the Smaller parts those are Executed by
java in Sequence and Timing Manner this is Called as Multithreaded In
this Program of java is divided into the Small parts those are Executed
by Compiler of java itself Java is Called as Interactive because Code of
java Supports Also CUI and Also GUI Programs.
8)Dynamic and Extensible Code:-
Java has Dynamic and Extensible Code Means With the Help of OOPS java
Provides Inheritance and With the Help of Inheritance we Reuse the Code
that is Pre-defined and Also uses all the built in Functions of java and
Classes.
9)Distributed:-
Java is a distributed language which means that the program can be
design to run on computer networks. Java provides an extensive library
of classes for communicating ,using TCP/IP protocols such as HTTP and
FTP. This makes creating network connections much easier than in C/C++.
You can read and write objects on the remote sites via URL with the same
ease that programmers are used to when read and write data from and to a
file. This helps the programmers at remote locations to work together
on the same project.
10) Secure:
Java was designed with security in mind. As Java is intended to be used
in networked/distributor environments so it implements several security
mechanisms to protect you against malicious code that might try to
invade your file system.
For
example: The absence of pointers in Java makes it impossible for
applications to gain access to memory locations without proper
authorization as memory allocation and referencing model is completely
opaque to the programmer and controlled entirely by the underlying
run-time platform .
11)Architectural Neutral:
One of the key feature of Java that makes it different from other
programming languages is architectural neutral (or platform
independent). This means that the programs written on one platform can
run on any other platform without having to rewrite or recompile them.
In
other words, it follows 'Write-once-run-anywhere' approach. Java
programs are compiled into byte-code format which does not depend on any
machine architecture but can be easily translated into a specific
machine by a Java Virtual Machine (JVM) for that machine. This is a
significant advantage when developing applets or applications that are
downloaded from the Internet and are needed to run on different systems.
12)Portable :
The portability actually comes from architecture-neutrality. In C/C++,
source code may run slightly differently on different hardware platforms
because of how these platforms implement arithmetic operations. In
Java, it has been simplified.
Unlike
C/C++, in Java the size of the primitive data types are machine
independent. For example, an int in Java is always a 32-bit integer, and
float is always a 32-bit IEEE 754 floating point number. These
consistencies make Java programs portable among different platforms such
as Windows, Unix and Mac .
13)Interpreted
: Unlike most of the programming languages which are either complied or
interpreted, Java is both complied and interpreted The Java compiler
translates a java source file to bytecodes and the Java interpreter
executes the translated byte codes directly on the system that
implements the Java Virtual Machine. These two steps of compilation and
interpretation allow extensive code checking and improved security .
14) High performance:
Java programs are complied to portable intermediate form know as
bytecodes, rather than to native machine level instructions and JVM
executes Java bytecode on. Any machine on which it is installed. This
architecture means that Java programs are faster than program or scripts
written in purely interpreted languages but slower than C and C++
programs that compiled to native machine languages.
Although
in the early releases of Java, the interpretation of by bytecode
resulted in slow performance but the advance version of JVM uses the
adaptive and Just in time (JIT) compilation technique that improves
performance by converting Java bytecodes to native machine instructions
on the fly.
