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JAVA

what is a class ?
  Ans: a class is a blue print  for object . the class defines  variables, methods  and objects . the object manipulates data through methods . these methods constitutes  a set of operations.
  class are the fundamental units in  an object -oriented programming . we use a  class to create  object (instances) each instance carries its own data .that is  data belongings to one object, it changed does not effect the data belonging to other object.
     Simple Structure of class :
   class demo {
                         int count;
                   public void display()
                                 {
                                      count ++;
                                 }
                      }

class demo1{
               
                   public static void main(String args[])
                         {
                         
                          }

                   }


  object :
           An object is an instance of a class . An object is known by a  name and every object contains  a  state
the state is determined by the value s of attributes .the state of object  can be  changed by calling method on it the  object is a software entity .that combines  a set of data  with a set operations to manipulate the data

simple structure of class and object :
                                                       class  demo{
                                                                           public static  void main (string args[])
                                                                                  {
                                                                                           demo  d1= new demo();
                                                                                   }
                                                                          }
in the above  program  , d1 is  the object of a class demo
with out  new key object is created  is possible
method:
 A method is the basic unit  of functionality  contained in a class . it contains the executable  body   that contain the applied to specific object  of class  .
 a method includes;
                         a name , parameters used to input some values,  a return type that give  out put of the program, abody  of executable code .
simple  syntax method;
public double  sum(double a, double b)
{
return (a+b);
}
 why  java is internet  language ?
   java is popular is it support internet programming . internet is used to connect the different systems across the globe . internet is used HTTP. java include two types of programs
one is  applications  and  applets. applets are java programs meant to be executed in the browser .browser is used to connect the internet .  
why java is dynamic and extensible
java is dynamic  language . at run time it can link standerad libraries ,class, objects , and methods

why java is distributed ?


who developed java ?
java was developed by the team led by gosling at Sun Micro systems

what are the benefits of object -oriented  programming ?
polymorphism  and inheritance  not available in traditional  language .
oops is closer to real life representations of the object .
data can be divided in public and private
program  development is easy.
what is the features of java /

 

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