abc.groovy

class Model {
    Model(seed)
    {
        this.seed = seed
    }
    int seed
}
class A {
    public Model seed
    A () {
        seed = new Model(Math.floor(Math.random() * 1000))
        println 'A() ' + seed
    }
    void a () { println 'A.instance.a()' }
    void f () { println 'A.instance.f() ' + seed }
    void xyz () { println 'A.instance.xyz() ' + seed }
}
class B extends A {
    public Model seed
    B () {
        super()
        seed = new Model(Math.floor(Math.random() * 1000))
        println 'B() ' + seed
    }
    void b () { println 'B.instance.b()' }
    void f () { println 'B.instance.f() ' + seed }
    void xyz () { 
        super.xyz()
        println 'B.instance.xyz() ' + seed 
    }
}
class C extends B {
    //public Model seed
    C () {
        super()
        seed = new Model(Math.floor(Math.random() * 1000))
        println 'C() ' + seed
    }
    void c () { println 'C.instance.c()' }
    void f () { println 'C.instance.f() ' + seed }
    void g () {
        f()
        super.f()
    }
    void xyz () { 
        super.xyz()
        println 'C.instance.xyz() ' + seed 
    }
}

def d = new B()
d.a()

println 'd instanceof A ' + (d instanceof A)
println 'd instanceof B ' + (d instanceof B)
println 'd instanceof C ' + (d instanceof C)

def e = new C()
e.g()

e.xyz()

abc.js

var jPre = jQuery('<pre/>').appendTo('body');
var preLog = function preLog(msg) {
    jPre.append(msg + "\n");
};

// A extends Object
var A = function A() {
    this.seed = Math.floor(Math.random() * 1000);
    preLog('A() ' + this.seed);
};
A.prototype.seed = null;
A.prototype.a = function a() {
    preLog('A.prototype.a()');
};
A.prototype.f = function f() {
    preLog('A.prototype.f() ' + this.seed);
};

// B extends A
var B = function B() {
    A.call(this);
    this.seed = Math.floor(Math.random() * 1000);
    preLog('B() ' + this.seed);
};
var tmpPrototypeA = function tmpPrototypeA() {};
tmpPrototypeA.prototype = A.prototype;
B.prototype = new tmpPrototypeA();
B.prototype.super = A.prototype;
B.prototype.constructor = B;
B.prototype.seed = null;
B.prototype.b = function b() {
    preLog('B.prototype.b()');
};
B.prototype.f = function f() {
    preLog('B.prototype.f() ' + this.seed);
};

// C extends B
var C = function C() {
    B.call(this);
    this.seed = Math.floor(Math.random() * 1000);
    preLog('C() ' + this.seed);
};
var tmpPrototypeB = function tmpPrototypeB() {};
tmpPrototypeB.prototype = B.prototype;
C.prototype = new tmpPrototypeB();
C.prototype.super = B.prototype;
C.prototype.constructor = C;
C.prototype.seed = null;
C.prototype.c = function c() {
    preLog('C.prototype.c()');
};
C.prototype.f = function f() {
    preLog('C.prototype.f() ' + this.seed);
};
C.prototype.g = function g() {
    this.super.super.f();
    this.super.f();
    this.f();
};

// new B instance
var d = new B();
// calling method a on instance d
d.a('called within scope of instance d');
// replace method a on A
A.prototype.a = function a(msg) {
    preLog('A.prototype.a() - ' + msg);
};
// calling method a on instance d
d.a('called within scope of instance d');

preLog('d instanceof A ' + (d instanceof A));
preLog('d instanceof B ' + (d instanceof B));
preLog('d instanceof C ' + (d instanceof C));

// new C instance
var e = new C();

e.a('called within scope of instance e');

e.g();