class A {

    public int a = 1;

    public int getA() { return a; }
}

class B extends A {

    public int a = 2;

    //public int getA() { return a + super.getA(); }

    //public int getA() { return a + super.a; }
}

public class FieldOverridingTest {

    public static void main(String[] args) {
	
	A instanceA = new A();
	System.out.println("(A) instanceA.getA() = " + instanceA.getA());

	instanceA = new B();
	System.out.println("(B) instanceA.getA() = " + instanceA.getA());

	B instanceB = new B();
	System.out.println("(B) instanceB.getA() = " + instanceB.getA());

    }
}

/* explanation:

data fields can be overridden, i.e. subclass may have a field with
the same name

BUT behavior is different from methods:

 compile-time (variable) type determines which field is accessed

RATIONALE:

 more efficient code possible,

 field overriding is rare, should possibly be avoided anyway

 only effects "public" and "protected" fields anyway,
 if we stick to "private" data fields + public accessor methods,
 there will be no problem 
 */