what is the difference between instance variable and static variable(class variable)

Instance variable

--> instance variable is a variable whose seperate copy is availabe to each object.

--> instance variables are created in the objects on heap memory.

Instance_variable_example.java

class Instance_var

{

      int a=5;

       void display()

      {

            System.out.println("a="+a);

      }

      }

class Instance_variable_example

{

      public static void main(String[] args)

      {

            Instance_static obj1=new Instance_static();

            ++obj1.a;

            obj1.display();

            Instance_static obj2=new Instance_static();

            obj2.display();

           

      }

}

OUTPUT:

a=6
a=5


Static variable

 --> a static variable(also known as class variable) is a variable whose single copy in memory is shared by all objects.

--> static variables are stored on method area.

Static_variable_example.java

class Static_var

{

      static int a=5;

      static void display()

      {

            System.out.println("a="+a);

      }

      }

class Static_variable_example

{

      public static void main(String[] args)

      {

            Instance_static obj1=new Instance_static();

            ++obj1.a;

            obj1.display();

            Instance_static obj2=new Instance_static();

            obj2.display();

           

      }

}

OUTPUT:

a=6

a=6