public class Test
{
    public static void main(String[] args) 
    {
        Person person = new Person();

        IRead read = new Book();

//看了这读物后想买下它
        person.read(read);
        
        //person.buy(read);
    }
}

//读物
interface IRead
{
    void content();
}

//商品
interface Goods
{
    void buy();
}

//图书
class Book implements IRead,Goods
{
    public void content()
    {
        System.out.println("沉思录....");
    }
    public void buy()
    {
        System.out.println("我买下这本书");
    }
}

//报纸
class NewPaper implements IRead,Goods
{
    public void content()
    {
        System.out.println("今天的头条是.....");
    }
    public void buy()
    {
        System.out.println("我买十份报纸");
    }
}

class Person
{

         //预览读物
    public void read(IRead read)
    {
        read.content();
    }
         
         //买下商品（这是要预览读物后才决定买不买的，不能首先就调用buy方法）
    public void buy(Goods goods)
    {
        goods.buy();
    }
}