Protected confusion..

[Mohnish Khiani]

package packA;


public class A 
{
    protected int pf;

}

package packB;
import packA.A;
public class B extends A
{
    public void act(A obj1,B obj2,C obj3)
    {
        pf=1;            //(1)
        obj1.pf=1;     //(2)
        obj2.pf=2;    //(3)
        obj3.pf=3;    //(4)
    }

}



public class C extends B
{
    public void act(A obj1,B obj2,C obj3)
    {
       
         pf=1;         //(5)
        obj1.pf=1;  //(6) 
        obj2.pf=2;  //(7)
        obj3.pf=3;  //(8)
    }

}

There are errors on line :5,6,7,8
and no error on line :3,4

Please explain how ?

[Ogeh Ikem]

class B can access a protected member declared in class A (located in a different package), only through inheritance i.e. only through a reference which is of type B (or a subclass of B).

class C can access a protected member declared in class A (located in a different package), only through inheritance i.e. only through a reference which is of type C (or a subclass of C).