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Introduction in java

1. Introduction

        JAVA is a high-level programming language developed by Sun Microsystems. Java was originally called OAK, and was designed for handheld devices and set-top boxes.

Some features of java:

             1. Simple: Some of the features that make java a simple language are no direct use of pointers, strong  memory management, automatic memory allocation and deallocation.

             2. Portable: Java language is portable as programs written in java can be run on any system having interpreter for JVM. Also, java has standard size irrespective of operating system or processor.

            3. Robust: Features that make java robust include powerful exception handling, type checking mechanism, strong memory allocation and automatic garbage collection mechanism.

4.    Architecture neutral: Code written in java is compiled into byte code instructions which can be interpreted on any machine using JVM and can be easily translated into native machine code. Also, compiler generates an architecture-neutral object file format that enable a Java application to execute anywhere on the network.

5.      Object oriented: Java is an object-oriented language it uses all object-oriented concepts including classes, objects, Inheritance, polymorphism, data binding. Also java has an extensive class library in core language package.

6.      Secure: All the programs in java are run in virtual machine sand box. Java uses the public key encryption system to allow the java applications to transmit over the Internet in the secure encrypted form. The byte code Verifier checks the classes after loading, class loader confines objects to unique namespace and security manager determines the accessibility options of a class like reading and writing a file to the local disk.

7.  Threading: Threads can be used in java for multiprocessing.
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