Features of Java(Buzzwords)

FEATURES OF JAVA:

• Java provides various features to the industry to develop distributed applications. They are:

1)      Simple

2)      Platform independent

3)      Architectural neutral

4)      Portable

5)      Multithreaded

6)      Distributed

7)      Secured

8)      Networked

9)      Interpreted

10)  Robusted

11)  Dynamic

12)  High performance

13)  OOPL

1)      Simple:

• No use of pointers (free from pointers) means complexity reduces.
• Dynamic Memory Allocation.
• Automatic garbage collection
• User friendly syntax.

2)                  Platform Independent:

• A program is said to be platform independent if and only if, it runs on every OS.
• The languages like C/C++ will run on only specific OS i.e. when we develop a C application on DOS, so that will be running on DOS only. It is not possible to transfer that application from DOS to UNIX even if we try to do the same we need to rebuild the application. Hence, the languages like C/C++ are treated as platform dependent languages.
• The languages like java will run on every OS irrespective to its provider.
• JVM converts one format to another format & thus we say that java is platform independent.

3)      Architectural Neutral:

o   A program is said to be an architectural neutral, if and only if that program is running on every processor, irrespective to their architectures.

 

 

4)      Portable:

Portability = Platform Independent + Architectural Neutral

5)      Multithreaded:

o   Thread – flow of control is known as a thread.

o   An application is said to be a multithreaded application, in which there exists n# of subprograms. For each such subprogram there exists a separate flow of control (thread). All such flow of controls are executing concurrently.

o   The languages like C/C++ are treated as Single Threaded Modeling Language (STML). Since there exist a single flow of control. In single threaded modeling languages, the program will be executing in sequential manner.

o   The languages like Java and Dot Net are treated as Multi Threaded Modeling Language (MTML). Since, there is a possibility of existence the multiple flows of controls. In multithreaded modeling languages, we can achieve concurrent execution. Hence, Java and Dot Net languages are suitable for developing internet applications i.e. distributed applications.

o   When we write a java application, by default there exist 2 types of threads. They are:

o   Background Thread

o   Foreground Thread

o   A background thread is a predefined thread or system defined thread which always executes to monitor the status of foreground threads.

o   Foreground threads are user defined threads which will be executing by manual calls to perform a meaningful operation.

On the other hand, Java is a Multi-threaded language-

Class….

{

                                    Public static void main (String args[])

                                    {

}

                                    ….

                                    ….

}

e.g.: gc () (Garbage Collector)

Here, there are 2 threads “main” an well as “gc()” which works concurrently.

Thus, we say Java is Multithreaded.

Also Garbage collector is a system Java program that executes to monitor the execution of Foreground thread and is collects the unreferenced memory spaces by running in periodic interval of time.

6)      Distributed:

o             An application is said to be distributed, if and only if which can be accessed across the globe.

o             A distributed service is one which runs in the context of browser or many servers and accessible to across the globe.

o             To develop distributed applications, we require trusted network architecture and it is preferred by large scale organizations.

o             Java supports to develop distributed applications. Hence, java is distributed.

7)      SECURED:

o   Java is a secured language.

o   To provide security to the applications which we develop, we must use the security features already developed by SUN Microsystems and supplied as a part of java software i.e. JDK.

8)      Networked:

o   Network is a collection of connected autonomous and non-autonomous machines or nodes.

o   We can have two types of networks-

o   Trusted Networks

o   Un-trusted Networks

o   A trusted network is one in which all clients are not directly dependent on the server i.e. clients are having the autonomous power. Trusted networks are used for developing distributed applications.

o   An un-trusted network is one in which clients are directly dependent on the server i.e. without starting the server, clients are unable to communicate. Such clients are known as non autonomous clients. Un-trusted networks are used to develop centralized distributed applications.

o   A centralized distributed application is one which always runs on single server.

For Example-

When we are connected to Internet and we open any website like www.gmail.com, etc. then we need not to worry that the person at server is there or not or etc, we always receive the page and we do not worry anything. This is Trusted Network.

Hence, we can say JAVA IS NETWORK.

9)      Interpreted:

o   Java is an interpreted language since:

o   Whenever we write a java application, it must be compiled by submitting it to JVM (Java Virtual Machine).

o   After compilation, we get an intermediate file with an extension “.class”. The “.class” file contains BYTE CODES/Intermediate Codes.

o   To run the “.class” file, we need to submit it to JVM again and JVM will read it line by line hence, while application is running, JVM is treated as Interpreter. Generally, interpreter takes a lot of time compare to compilation but as a part of JVM a small program called JIT (Just-in-time) is added. Hence, JVM will interpret the byte codes very fast i.e. Interpretation will take very less time than the compilation in the java environment.

o   In Java Runtime Environment (JRE), the JVM is treated as Compiler cum Interpreter.

o   The following figure describes the compilation and interpretation process in Java:

10)   Robusted:

o        Java is a robusted language, because of the following reasons:

o   Run time errors can be processed effectively. Runtime errors are those which are occurring at runtime. If we come across any error at runtime, such type of errors are known as runtime errors or exceptions.

o   Java contains readily available Garbage Collector for collecting un-used or unreferenced memory locations or improving the performance of java programming.

o   Java programmer can develop java applications without using the concept of pointers hence, application development time is less and complexity will be reduced.

o   Services are provided without any interruptions. e.g.: All websites. 24x7 service is provided.

11)  Dynamic:

• Java is a dynamic language because of the following reasons:
• Java always supports Dynamic Memory Allocation for avoiding the Static Memory Allocation problems.
• The websites which we develop using Java provides dynamic access to number of the clients i.e. any server side program can be accessed by n# of clients concurrently. There is no restriction for the number of clients.

12)  High Performance:

• Java is a high performance language because whichever application we develop in java runtime environment is free from pointers and it will be converted in the form of pointers when get compiled.
• Any application which is executing with the concept of pointers will be having high performance.
• Java contains rich set of API (Application Programming Interface). If we use the predefined API as a part of our java application, its performance will be improved.

13)  Object-Oriented Programming Language:

o   Java supports, all the OOP’s principle, so we can say that it is an Object Oriented Programming Language.