What is java ?




 

  • Java is a General Purpose Programming Language. 
  • They are used for Software and Application Development. 
  • java is a High Level Programming Language. 
  • It was started by Sun-micro system in 1995. 
  • James Gosling is one of its major developers. 
  • This is Platform Independent Language. 
  • You can run the code written in it in any platform or os.


USE OF JAVA

  • This Computer Programming Language has only one purpose. 
  • Whatever code is written in it, it should be run in all computers. 
  • Whether or not both machines are the same or not, 
  • I mean to say, code written in C ++ is never the same Execute in another machine.
  • for example whether it is an OS (Windows or Mac). 
  • Code written in Windows is never run in Mac OS, but it is wrong in the case of java.
  • It is used to create web based programming and mobile application software. 
  • All the operating systems of Android like Kitkat, Lolipop, Oreo.
  • have all been developed from this programming language. 
  • In today's time, all the web pages run on Java Script. 
  • The question in your mind will be how does Code Execute happen.


History of Java Version

  • JDK Alpha and Beta (1995)
  • JDK 1.0 (23 Jan, 1996)
  • JDK 1.1 (19 Feb, 1997)
  • J2SE 1.2 (8 Dec, 1998)
  • J2SE 1.3 (8 May, 2000)
  • J2SE 1.4 (6 Feb, 2002)
  • J2SE 5.0 (30 Sep, 2004)
  • Java SE 6 (11 Dec, 2006)
  • Java SE 7 (28 July, 2011)
  • Java SE 8 (18 March, 2014)

Where is the use of Java

  • Applets
  • J2EE
  • JavaBeans

Characteristics

  • Everything in Object Oriented –java is Object Oriented. 
  • With the help of Object Model, you can easily create app / sw with long code.

Platform independent :-  
  • This is a typical language in which software written in it can run in all operating systems. 
  • Which is also called Cross Platform. 
  • But if we talk about C and C ++, then both these platforms are Dependent Language.
Simple :- 

  • You can understand this easily and can write it easily, this is its quality. 
  • That is why it is called Simple. 
  • If you have understood the basic concept of Oops, then no one can stop you from becoming a master in java.

Secure :-
 
  • This is very popular because of its security feature. 
  • Virus Free can develop Tamper Free System software. 
  • Public Key Encryption is used in Authentication Technique.

Architectural-neutral :-
 
  • The code generated by the compiler is the byte code. 
  • The code that you can run anywhere, in any operating system and processor. 
  • Therefore, it is being called Architectural Neutral. 
  • For this, it is mandatory to have JVM which is in all the systems.
Portable :-
 
  • Platform Independent. Because both java and Compiler are written in ANSI C.

Robust :-
 
  • All the programs written in it are strong. 
  • Strong does not mean a strong thing like iron. 
  • When PROGRAM is RUN, there is no error in it. 
  • Because compile time and run time error checking mechanism is used.

Multi-threaded :-
 
  • Because of these features, you can write programs that can perform multiple tasks. 
  • Meaning there will be an application and in that you can do all the tasks.

High Performance :- 

  • Just in Time Compilers java's performance is quite good.
Distributed :- 

  • Due to this nature, the status of the Internet's distributed environment has maintained its status.

Dynamic :- 

  • This is Dynamic Programming. It can adapt to any environment.

JAVA EDITORS



EXAMPLE

  • A "Hello World!" is a simple program that outputs Hello World! on the screen. 
  • Since it's a very simple program, it's often used to introduce a new programming .




hello.java


 class hello{  
    public static void main(String args[]){  
     System.out.println("WELCOME CODES WITH SUNNY");  
    }  
 }

OUTPUT


WELCOME CODES WITH SUNNY


Sum of Two Number in Java

  • Here we will see Two programs to Add two Integer numbers, 
  • In the First program we specify the value of both the numbers in the program.


sum.java

public class sum {

   public static void main(String[] args) {
        
      int number1 = 50, number2 = 50, sum;
      sum = number1 + number2;

      System.out.println("Sum of Two Numbers => "+sum);
   }
}

OUTPUT

Sum of Two Numbers => 100