Polymorphic Bean reference and Java polymorphism

[Rajat Sharmanaive]

Hi

I posted this mistakenly at a wrong forum. Hope to get some help this time. Learning through HFSJ by K&B. Following is my query from the same.

The jsp standard action:

   
 <jsp:useBean id=personBean type="PersonBean" class="EmployeeBean" scope="request">  
 </jsp:useBean>  

In the generated servlet, translates to:

  PersonBean personBean = new EmployeeBean();  

Following are my 2 beans:

    abstract public class PersonBean {  
        public String getName(){  
            return name;  
        }  
          
        public void setName(String name){  
                this.name=name;  
        }  
        private String name;  
    }  
      
public class EmployeeBean extends PersonBean{ 
      public int getEmpId(){  
            return empId;  
        }  
          
        public void setEmpId(int empId){  
                this.empId=empId;  
        }  
            private int empId;  
    }  

But i notice that the reference variable personBean which is of the superclass type is able to access (and set) the subclass bean functions like setEmpId() which are not overridden. From previous knowledge I understand that dynamic dispatch happens only for overridden functions. Is eveything fine here. Please throw some light.

Sincerely hoping this time I have posted it correctly
Thanks

[Bear Bibeault]

Please do not post the same question more than once. This topic is closed.