Stateless, Stateful Java Objects

These days people are talking more stateless and stateful objects.

State of the Object:

            Always represents it's instance variables.

Class Calculator {

      public int add(int a, int b) {

      }

}

Class Person {

        private String name;

       

         public String getName() {

              return this.name;

         }

        

          public void setName(String name) {

              this.name = name;

          }

}

Calculator calc = new Calculator();

    calc object having any instance variables , answer will be no. The object doesn't have any instance varialbe  we can call that object as stateless object.

Person ram = new Person();

         ram object having instance varialbe. But I am not update the instance varialbe, means not initializing the state. 

ram is statlesss object, 

ram.setName("Ramesh");

Now ram object initiliazing the instance variable with "Ramesh", then ram object having state.

now ram object became stateful object.

In design pattern state means object internal instance variable.