Java面向对象，接口，不太懂接口的使用

class Phone{
    protected String phoneNumber;
    public Phone(String phoneNumber){
        this.phoneNumber = phoneNumber;
    }
}

interface Internet{
    void getWeb();
}

class SmartPhone extends Phone implements Internet{
    @Override
    public void getWeb() {
        System.out.println("智能手机" + phoneNumber + "正在上网");
    }

    public SmartPhone(String phoneNumber){
        super(phoneNumber);
    }
}

class Test{

    public static void main(String[] args) {
        SmartPhone smartPhone = new SmartPhone("13812345678");
        smartPhone.getWeb();
    }
}

采纳下吧