5-13练习

public class Balloon implements IFly {

public void fly() {

System.out.println("气球飞上天空");

}

}

public interface IFly {

default void fly() {

System.out.println("sasda");

}

public class Test33 {

IFly one=new Balloon();

IFly two=new Bird();

IFly three=new Plane();

one.fly();

two.fly();

three.fly();

}

这个地方为啥会有红线，我在练习题这能运行，在自己的eclipse 这会报错