package day_10; //创建接口Port (在包中按ALT+Insert,将class改为interface)
public interface Port { void fly(); //接口中方法默认是用public abstract修饰 } package day_10; public class Bird implements Port { @Override public void fly() { //重写接口中的抽象方法(ctrl+i) System.out.println("小鸟会飞。。。。。。。。"); } } package day_10; public class Plane implements Port { @Override public void fly() { System.out.println("飞机有飞行功能。。。。。。"); } } package day_10; public class Test { public static void main(String[] args) { Port port; //接口是一种引用数据类型 port = new Bird(); //接口引用需要赋值实现类对象 port.fly(); port = new Plane(); port.fly(); } }