/*
定義圖書類
*/
public class Book {
    private int id;
    private String name;
    private double price;
    private int stock;
    //無參構(gòu)造
    public Book() {
    }
    //帶四個參數(shù)的構(gòu)造
    public Book(int id, String name, double price, int stock) {
        this.id = id;
        this.name = name;
        this.price = price;
        this.stock = stock;
    }

    public int getId() {
        return id;
    }

    public void setId(int id) {
        this.id = id;
    }

    public String getName() {
        return name;
    }

    public void setName(String name) {
        this.name = name;
    }

    public double getPrice() {
        return price;
    }

    public void setPrice(double price) {
        this.price = price;
    }

    public int getStock() {
        return stock;
    }

    public void setStock(int stock) {
        this.stock = stock;
    }
}

/*
定義訂單項類
*/
public class OrderItem {
    private Book book;
    private int num;

    public OrderItem() {
    }
    public OrderItem(Book book, int num) {
        this.book = book;
        this.num = num;
    }

    public Book getBook() {
        return book;
    }

    public void setBook(Book book) {
        this.book = book;
    }

    public int getNum() {
        return num;
    }

    public void setNum(int num) {
        this.num = num;
    }
}

/*
訂單類
*/
public class Order {
    private String orderID;
    private OrderItem[] items = new OrderItem[3];
    private double totalMoney;

    public Order() {
    }

    public Order(String orderID) {
        this.orderID = orderID;
    }

    public String getOrderID() {
        return orderID;
    }

    public void setOrderID(String orderID) {
        this.orderID = orderID;
    }

    public OrderItem[] getItems() {
        return items;
    }

    public void setItems(int i,OrderItem item) {
        items[i]=item;
    }

    public double getTotalMoney() {
        for (int i = 0; i < items.length; i++) {
            totalMoney += items[i].getNum()*items[i].getBook().getPrice();
        }
        return totalMoney;
    }
}

/*
打印圖書信息的方法
*/
    private static void printBooks(Book[] books) {
        books[0]=new Book(1,"Java2實用教程",10,20);
        books[1]=new Book(2,"計算機網(wǎng)絡(luò)原理",20,20);
        books[2]=new Book(3,"概率論數(shù)理統(tǒng)計",30,20);

        System.out.println("圖書編號\t圖書名稱\t\t\t圖書單價\t圖書庫存");
        for (int i = 0; i < books.length; i++) {
            Book b=books[i];
            System.out.println("\t"+b.getId() +"\t\t"+b.getName()+"\t\t"+b.getPrice()+"\t\t"+b.getStock());
        }
    }

/*
購買圖書的方法
*/
    private static Order buy(Book[] books) {
        Order order = new Order("001");
        Scanner sc=new Scanner(System.in);
        for (int i = 0; i < books.length; i++) {
            System.out.println("請輸入圖書的編號：");
            int id = sc.nextInt();
            System.out.println("請輸入購買的數(shù)量：");
            int num = sc.nextInt();
            OrderItem item = new OrderItem(books[id-1],num);
            order.setItems(i,item);
        }
        return order;
    }

/*
打印訂單信息方法
*/
    private static void printInfo(Order order) {
        System.out.println("訂單編號："+order.getOrderID());
        System.out.println("圖書名稱\t\t圖書單價\t購買的數(shù)量");
        OrderItem[] items = order.getItems();
        for (int i = 0; i < items.length; i++) {
            System.out.println(items[i].getBook().getName()+"\t"+items[i].getBook().getPrice()+"\t\t"+items[i].getNum());
        }
        System.out.println("----------------------------------");
        System.out.println("總金額："+order.getTotalMoney());
    }

    public static void main(String[] args) {
        Book[] books = new Book[3];

        //調(diào)用打印圖書信息的方法
        printBooks(books);

        //調(diào)用購買圖書的方法
        Order order = buy(books);

        //調(diào)用打印訂單信息方法
        printInfo(order);
    }