package com.example.shape; class Shape { public void draw() { System.out.println("绘制形状"); } } class Circle extends Shape { @Override public void draw() { System.out.println("绘制圆形"); } } class Rectangle extends Shape { @Override public void draw() { System.out.println("绘制矩形"); } } public class Shapetest { public static void drawShape(Shape s) { s.draw(); } public static void main(String[] args) { Shape circle = new Circle(); drawShape(circle); Shape rectangle = new Rectangle(); drawShape(rectangle); Shape general = new Shape(); drawShape(general); } }