入門 - 第2ステップ

// House.java という名前で保存
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;
    }
}

// この例はScilabディストリビューションに含まれます.
directory=SCI+"/modules/external_objects_java/examples/com/foo/"
// これらを全てコンパイルします
jcompile(ls(directory + "/*.java"))