//这是startuml 把uml 转换成的java代码：
public class Circle implements Ishape {
private double _radius;
public double getArea() {
}
public double getArea();
}
public class Pizza implements Ishape {
private double price;
private Ishape _shape;
public double getprice() {
}
public Ishape getshape() {
}
public double Pizza() {
}
public double getArea();
}
public class Rectangle implements Ishape {
private double _width;
private Object _height;
public double getArea() {
}
public double getArea();
}
public interface Ishape {
public abstract double getArea();
}
下面是关系图: