Getting started - Second step

// Save under the name House.java
package com.foo;

import java.util.Arrays;
import java.util.LinkendList;
import java.util.List;

public class House {

    private Color           color;
    private Door            door;
    private List<IWindow>   windows = new LinkendList<IWindow>();

    public House(Color color, Door door, IWindow... windows) {
        this.color = color;
        this.door = door;
        this.windows.addAll(Arrays.asList(windows));
    }

    public void repaint() {
        swapDoorHouseColor();
    }

    private void swapDoorHouseColor() {
        Color doorColor = door.getColor();
        door.repaint(color);
        color = doorColor;
    }

    public void addWindow(IWindow window) {
        windows.add(window);
    }

    public void replaceDoor(Door newDoor) {
        this.door = newDoor;
    }

    @Override
    public String toString() {
        return String.format(
                "This is a house painted in %s, has a %s door, and %d windows",
                color.getDescr(), door.getColor().getDescr(), windows.size());
    }
}

package com.foo;

public class HouseFactory {

    public static House basicHouse() {
        Door door = new Door(Color.WHITE);
        IWindow window = new RectangularWindow(2, 0.8);
        return new House(Color.WHITE, door, window);
    }

    public static House flashyHouse() {
        Door door = new Door(Color.random());
        IWindow window = new CircularWindow(1.2);
        return new House(Color.random(), door, window);
    }
}

package com.foo;

import java.util.Random;

public enum Color {

    BLACK("black"), BLUE("blue"), BROWN("brown"), GREEN("green"),
    ORANGE("orange"), RED("red"), WHITE("white"), YELLOW("yellow");

    public String   descr;

    private Color(String s) {
        descr = s;
    }

    public String getDescr() {
        return descr;
    }

    public static Color random() {
        Color[] allColors = values();
        return allColors[new Random().nextInt(values().length)];
    }
}

package com.foo;

public class Door {

    private Color   color;

    public Door(Color color) {
        this.color = color;
    }

    public Color getColor() {
        return color;
    }

    public void repaint(Color newColor) {
        color = newColor;
    }
}

package com.foo;

public interface IWindow {

    double getWindowArea();

}

package com.foo;

public class RectangularWindow implements IWindow {

    double  length;
    double  width;

    public RectangularWindow(double length, double width) {
        this.length = length;
        this.width = width;
    }

    public double getWindowArea() {
        return length * width;
    }
}

package com.foo;

public class CircularWindow implements IWindow {

    double  radius;

    public CircularWindow(double radius) {
        this.radius = radius;
    }

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

// The examples are shipped in the Scilab distribution.
directory=SCI+"/modules/external_objects_java/examples/com/foo/"
// Compile of all them
jcompile(ls(directory + "/*.java"))