Inheritance doubt

[Vidya Venkatesh]

hi friends, in this program given below , the print() method is inherited by the subclass. Then why does it print the value of variable s of the class Base ?
Thanx a lot
Vidya
class Base{
String s = "Base";
void print(){
System.out.println(s);
}
}
class Derived extends Base{
String s = "Derived";
}
public class Test {
public static void main(String[] args){
Derived b = new Derived();
b.print();
System.out.println(b.s);
}
}
[ April 29, 2003: Message edited by: Vidya Venkatesh ]

[Rajeshwari Natarajan]

The Derived class inherits the print() method of base class. It does not define its own implementation of print() overriding the base class method.
So when u invoke the print() method, the base class method is called and the string in base class is printed.

[Roger Chung-Wee]

At compile time, class Base knows nothing about class Derived. What the compiler does is to statically bind print method to String s in Base. So, when the inherited print method is called, it's the value of String s at compile time ("Base") which is printed out. String s in Derived is not used at runtime, it is only there to test you.
[ April 29, 2003: Message edited by: Roger Chung-Wee ]

[Francis Siu]

hi Vidya
Let me do the trace help you to go through this programme

 
class Base
{
  String s = "Base";
  //Here I write the default constructor
  public Base()//(4)
  {
  }
  void print() //(6)
  {
    System.out.println(s); //(7)
  }
} 
class Derived extends Base
{
  String s = "Derived";
  //Here I write the default constructor
  public Derived()//(2)
  {
    //default constructor if the class extends
    //other class
    super();//(3)
  }
}
public class Test 
{ 
  public static void main(String[] args)
  {
    Derived b = new Derived();//(1)
    b.print(); //(5)
    System.out.println(b.s);(8)
  }
}
 

Firstly,print out (7)
Base
Then,print out (8) because it use the string itself
Derived
If it is not clear,please post it again

[Dan Chisholm]

A method in a subclass may override a method in a superclass that has the same name and parameter list. However, fields in a subclass do not override fields in a superclass. Instead, a field in a subclass will "hide" a field with the same name in a superclass. The behavior of overridden methods is different from the behavior of hidden fields.
Section 8.3.3.2 of the Java Language Specification covers "Hiding of Instance Variables".