Now I post the code:

I have an interface Shape
I have a class Point implements Shape
I have a class Circle extends Point

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(1)when I want to create an anonymous class that implements an
interface I do:
class java_test
{
    public static void doShape(Shape s)
    {
        double v, a;

        v = s.volume();

        a = s.area();

        System.out.println("Volume: " + v + " Area: "+ a);
    }

    public static void main(String args[])
    {
        doShape(
                new Shape() // anonymous
                {
                    public double area() {return 0.0;}
                    public double volume() {return 0.0;}
                }
                );

}
here new Shape is like I was doing:
class Anon implements Shape() {};
Anon a = new Anon();
doShape(a);
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(2)when I want to create an anonymous class that extends a superclass
I do:

class java_test
{
    public static void doPoint(Point p)
    {
        System.out.println("Area: " + p.area());
    }

    public static void main(String args[])
    {
        doPoint(
                new Point() // anon
                {
                                       // HERE THE DOUBT ERROR
                    public double radius;

                    public double area()
                    {
                        return Math.PI * radius * radius;
                    }

                }
                );
    }
}
here is like I was doing class Anon extends Point {} but here is my
problem. When in the real
code I do class Circle extends Point then in Circle I have a "radius"
variable where I pass
a value... and so when I call area() it returns a correct value. In
the anonymous example
I cannot do a correct area() overriding. Infact in Point area()
returning 0.0 because a Point
cannot have an area...AND THIS IS A BIG DOUBT
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