AS3 - Hit Test Object In different classes - actionscript-3

Question

I am making pong
I need the ball to sense detection of the walls and two paddles
How can I achieve this without making a central class and just keep the 3 different classes for Paddle 1 paddle 2 and Ball?
BALL CLASS
package {
import flash.display.MovieClip;
import flash.events.Event;
import flash.events.KeyboardEvent;
public class Grey extends MovieClip {
/*var blues:Array = new Array
var blue:Blue = new Blue();*/
private var changes:Boolean
private var directions
private var speed:int = 20;
public function Grey() {
// constructor code
stage.addEventListener(Event.ENTER_FRAME, loop)
/*stage.addEventListener(KeyboardEvent.KEY_DOWN, pressed)*/
}
function loop(e:Event) {
movements();
hitTesting();
}
function movements() {
if (changes==true) {
directions = -1;
} else {
directions = 1;
}
x+=speed * directions;
}
function hitTesting() {
/*if (this.hitTestObject(blues)) {
changes = true;
}*/
}
}
}
Paddle 1 Class (PLAYER)
package {
import flash.display.MovieClip;
import flash.events.Event;
import flash.events.KeyboardEvent;
public class Blue extends MovieClip {
private var speed:int = 10;
public function Blue() {
// constructor code
stage.addEventListener(Event.ENTER_FRAME, loop);
/*stage.addEventListener(KeyboardEvent.KEY_DOWN, pressed)*/
}
function loop(e:Event) {
if (parent.mouseY > 0 && parent.mouseY < 360) {
y = parent.mouseY;
}
}
/*function pressed(e:KeyboardEvent) {
switch(e.keyCode) {
case 38:
y-=speed;
break;
case 40:
y+=speed;
break;
}
}*/
}
}
Paddle 2 Class (CPU)
package {
import flash.display.MovieClip;
import flash.events.Event;
import flash.events.KeyboardEvent;
public class Red extends MovieClip {
var greyy:Grey = new Grey();
private var speed:int = 10;
public function Red() {
// constructor code
stage.addEventListener(Event.ENTER_FRAME, loop);
/*stage.addEventListener(KeyboardEvent.KEY_DOWN, pressed)*/
}
function loop(e:Event) {
if (greyy.y > y) {
y-=3;
} else if(greyy.y < y){
y+=3;
}
}
}
}