package strategy; /** * @author ï¼ CodeWater * @create ï¼2022-06-24-17:31 * @Function Description ï¼ */ public abstract class Duck { public Duck() { } public abstract void display();//æ¾ç¤ºé¸åä¿¡æ¯ public void quack() { System.out.println("é¸åååå«~~"); } public void swim() { System.out.println("é¸å伿¸¸æ³³~~"); } public void fly() { System.out.println("é¸åä¼é£ç¿~~~"); } }