Create A Program That Calculate Price Of Carpeting For Rectangle Rooms

I am not getting any syntax errors but the program simply does nothing when I run it.

I literally just get "run: BUILD SUCCESSFUL (total time: 3 seconds)".

So basically, I need to create a program that calculates the price of carpeting for rectangle rooms.(multiply the area of the floor by the price per square foot of the carpet).

-The RoomDimension class should have two fields: one for length and one for width, and a method that returns the area of the room
-The RoomCarpet class that has a RoomDimension object as a field, a field for the cost of carpet per square foot, and a method that returns the total cost of the carpet

Here is what I have:

package roomdimension.java;
public class RoomDimension {

private double length=0;
private double width=0;
private final double area = length * width;

public void RoomDimension(double len, double w)

[Code] ....