RectanglePlus.java

//defining the interface
interface Relatable{
    public int isLargerThan(Relatable other);
}

class Point {
    public Point(int m, int n){
        this.x = m;
        this.y = n;
    }
    int x;
    int y;
}
public class RectanglePlus implements Relatable{
    public int width = 0;
    public int height = 0;
    public Point origin;

    // four constructors
    public RectanglePlus() {
        origin = new Point(0, 0);
    }
    public RectanglePlus(Point p) {
        origin = p;
    }
    public RectanglePlus(int w, int h) {
        origin = new Point(0, 0);
        width = w;
        height = h;
    }
    public RectanglePlus(Point p, int w, int h) {
        origin = p;
        width = w;
        height = h;
    }

    // a method for moving the rectangle
    public void move(int x, int y) {
        origin.x = x;
        origin.y = y;
    }

    // a method for computing
    // the area of the rectangle
    public int getArea() {
        return width * height;
    }
//Implementing the interface
    @Override
    public int isLargerThan(Relatable other) {
//        type casting tells the compiler what the object really is

        RectanglePlus otherRect =
                (RectanglePlus)other;
        if (getArea()<otherRect.getArea())
            return -1;
        else if (getArea()>otherRect.getArea())
            return 1;
        else
            return 0;
    }

    public Object findLargest(Object object1,Object object2){
        Relatable obj1 = (Relatable)object1;
        Relatable obj2 = (Relatable)object2;
        if (obj1.isLargerThan(obj2)>0)
            return object1;
        else
            return object2;
    }
}