疑似stdIn.readline()方法无法读取。问题位于第430行处，使用注释内容，即
product=catalog.getProduct("A001");
时可以正常输出预期结果。
尝试输出stdIn.readline()方法发现输出为空，即读取内容为空
import java.io.*;
import java.util.*;
import java.text.*;
/**
* This class implements a gourmet coffee system.
*
* @author author name
* @version 1.1.0
* @see Product
* @see Coffee
* @see CoffeeBrewer
* @see Catalog
* @see OrderItem
* @see Order
*/
public class GourmetCoffee {
private static BufferedReader stdIn =
new BufferedReader(new InputStreamReader(System.in));
private static PrintWriter stdOut =
new PrintWriter(System.out, true);
private static PrintWriter stdErr =
new PrintWriter(System.err, true);
private static final NumberFormat CURRENCY =
NumberFormat.getCurrencyInstance();
private Catalog catalog;
private Order currentOrder;
private Sales sales;
/**
* Loads data into the catalog and starts the application.
*
* @param args String arguments. Not used.
* @throws IOException if there are errors in the input.
*/
public static void main(String[] args) throws IOException {
GourmetCoffee application = new GourmetCoffee();
application.run();
}
/**
* Constructs a <code>GourmetCoffee</code> object and
* initializes the catalog and sales data.
*
* @param initialCatalog a product catalog
*/
private GourmetCoffee() {
this.catalog = loadCatalog();
this.sales = loadSales(this.catalog);
this.currentOrder = new Order();
}
/**
* Creates an empty catalog and then add products to it.
*
* @return a product catalog
*/
private Catalog loadCatalog() {
Catalog catalog = new Catalog();
catalog.addProduct(new Coffee(
"C001", "Colombia, Whole, 1 lb", 17.99,
"Colombia", "Medium", "Rich and Hearty", "Rich", "Medium", "Full"));
catalog.addProduct(new Coffee(
"C002", "Colombia, Ground, 1 lb", 18.75,
"Colombia", "Medium", "Rich and Hearty", "Rich", "Medium","Full"));
catalog.addProduct(new Coffee(
"C003", "Italian Roasts, Whole, 1 lb", 16.80,
"Latin American Blend", "Italian Roast", "Dark and heavy",
"Intense", "Low", "Medium"));
catalog.addProduct(new Coffee(
"C004", "Italian Roasts, Ground, 1 lb", 17.55,
"Latin American Blend", "Italian Roast", "Dark and heavy",
"Intense", "Low", "Medium"));
catalog.addProduct(new Coffee(
"C005", "French Roasts, Whole, 1 lb", 16.80,
"Latin American Blend", "French Roast", "Bittersweet, full intense",
"Intense, full", "None", "Medium"));
catalog.addProduct(new CoffeeBrewer(
"B001", "Home Coffee Brewer", 150.00,
"Brewer 100", "Pourover", 6));
catalog.addProduct(new CoffeeBrewer(
"B002", "Coffee Brewer, 2 Warmers", 200.00,
"Brewer 200", "Pourover", 12));
catalog.addProduct(new CoffeeBrewer(
"B003", "Coffee Brewer, 3 Warmers", 280.00,
"Brewer 210", "Pourover", 12));
catalog.addProduct(
new Product("A001", "Almond Flavored Syrup", 9.00));
catalog.addProduct(
new Product("A002", "Irish Creme Flavored Syrup", 9.00));
catalog.addProduct(
new Product("A003", "Mint Flavored syrup", 9.00));
catalog.addProduct(
new Product("A004", "Caramel Flavored Syrup", 9.00));
catalog.addProduct(
new Product("A005", "Gourmet Coffee Cookies", 12.00));
return catalog;
}
/**
* Initializes the sales object.
*/
private Sales loadSales(Catalog catalog) {
Sales sales = new Sales();
Order[] orders = new Order[6];
orders[0] = new Order();
orders[0].addItem(new OrderItem(catalog.getProduct("C001"), 5));
sales.addOrder(orders[0]);
orders[1] = new Order();
orders[1].addItem(new OrderItem(catalog.getProduct("C002"), 2));
orders[1].addItem(new OrderItem(catalog.getProduct("A001"), 2));
orders[1].addItem(new OrderItem(catalog.getProduct("A003"), 2));
sales.addOrder(orders[1]);
orders[2] = new Order();
orders[2].addItem(new OrderItem(catalog.getProduct("B002"), 1));
orders[2].addItem(new OrderItem(catalog.getProduct("A003"), 3));
sales.addOrder(orders[2]);
orders[3] = new Order();
orders[3].addItem(new OrderItem(catalog.getProduct("B003"), 2));
orders[3].addItem(new OrderItem(catalog.getProduct("C001"), 3));
orders[3].addItem(new OrderItem(catalog.getProduct("C003"), 3));
orders[3].addItem(new OrderItem(catalog.getProduct("C005"), 3));
orders[3].addItem(new OrderItem(catalog.getProduct("A001"), 3));
orders[3].addItem(new OrderItem(catalog.getProduct("A004"), 2));
sales.addOrder(orders[3]);
orders[4] = new Order();
orders[4].addItem(new OrderItem(catalog.getProduct("B001"), 1));
orders[4].addItem(new OrderItem(catalog.getProduct("C002"), 2));
orders[4].addItem(new OrderItem(catalog.getProduct("C003"), 2));
orders[4].addItem(new OrderItem(catalog.getProduct("A001"), 2));
orders[4].addItem(new OrderItem(catalog.getProduct("A002"), 6));
sales.addOrder(orders[4]);
orders[5] = new Order();
orders[5].addItem(new OrderItem(catalog.getProduct("B001"), 1));
orders[5].addItem(new OrderItem(catalog.getProduct("C001"), 1));
orders[5].addItem(new OrderItem(catalog.getProduct("C005"), 5));
orders[5].addItem(new OrderItem(catalog.getProduct("A001"), 5));
orders[5].addItem(new OrderItem(catalog.getProduct("A004"), 4));
sales.addOrder(orders[5]);
return sales;
}
/*
* Presents the user with a menu of options and executes the
* selected task.
*/
private void run() throws IOException {
int choice = getChoice();
while (choice != 0) {
if (choice == 1) {
displayCatalog();
} else if (choice == 2) {
displayProductInfo();
} else if (choice == 3) {
displayOrder();
} else if (choice == 4) {
addModifyProduct();
} else if (choice == 5) {
removeProduct();
} else if (choice == 6) {
saleOrder();
} else if (choice == 7) {
displayOrdersSold();
} else if (choice == 8) {
displayNumberOfOrders(readProduct());
} else if (choice == 9) {
displayTotalQuantityOfProducts();
}
choice = getChoice();
}
}
/*
* Displays a menu of options and verifies the user's choice.
*
* @return an integer in the range [0,7]
*/
private int getChoice() throws IOException {
int input;
do {
try {
stdErr.println();
stdErr.print(
"[0] Quit\n"
+ "[1] Display catalog\n"
+ "[2] Display product\n"
+ "[3] Display current order\n"
+ "[4] Add|modify product to|in current order\n"
+ "[5] Remove product from current order\n"
+ "[6] Register sale of current order\n"
+ "[7] Display sales\n"
+ "[8] Display number of orders with a specific product\n"
+ "[9] Display the total quantity sold for each product\n"
+ "choice> ");
stdErr.flush();
input = Integer.parseInt(stdIn.readLine());
stdErr.println();
if (0 <= input && 9 >= input) {
break;
} else {
stdErr.println("Invalid choice: " + input);
}
} catch (NumberFormatException nfe) {
stdErr.println(nfe);
}
} while (true);
return input;
}
/**
* Displays the catalog.
*/
public void displayCatalog() {
int size = this.catalog.getNumberOfProducts();
if (size == 0) {
stdErr.println("The catalog is empty");
} else {
for (Product product : this.catalog) {
stdOut.println(product.getCode() + " " +
product.getDescription());
}
}
}
/**
* Displays the information of a product
*/
public void displayProductInfo() throws IOException {
Product product = readProduct();
stdOut.println(" Description: " + product.getDescription());
stdOut.println(" Price: " + product.getPrice());
if (product instanceof Coffee) {
Coffee coffee = (Coffee) product;
stdOut.println(" Origin: " + coffee.getOrigin());
stdOut.println(" Roast: " + coffee.getRoast());
stdOut.println(" Flavor: " + coffee.getFlavor());
stdOut.println(" Aroma: " + coffee.getAroma());
stdOut.println(" Acidity: " + coffee.getAcidity());
stdOut.println(" Body: " + coffee.getBody());
} else if (product instanceof CoffeeBrewer) {
CoffeeBrewer brewer = (CoffeeBrewer) product;
stdOut.println(" Model: " + brewer.getModel());
stdOut.println(" Water Supply: " + brewer.getWaterSupply());
stdOut.println(" Number of Cups: " + brewer.getNumberOfCups());
}
}
/**
* Displays the current order.
*/
public void displayOrder() {
int size = this.currentOrder.getNumberOfItems();
if (size == 0) {
stdErr.println("The current order is empty");
} else {
for (OrderItem orderItem : this.currentOrder) {
stdOut.println(orderItem.toString());
}
stdOut.println("Total: " +
CURRENCY.format(this.currentOrder.getTotalCost()));
}
}
/**
* Modifies the current order: if the specified product is not already
* part of the order, it is added; otherwise, the quantity of the
* specified product is updated.
*/
public void addModifyProduct() throws IOException {
Product product = readProduct();
int quantity = readQuantity();
OrderItem orderItem = this.currentOrder.getItem(product);
if (orderItem == null) {
this.currentOrder.addItem(new OrderItem(product, quantity));
stdOut.println("The product " + product.getCode()
+ " has been added");
} else {
orderItem.setQuantity(quantity);
stdOut.println("The quantity of the product " +
product.getCode() + " has been modified");
}
}
/**
* Removes a product from the current order.
*/
public void removeProduct() throws IOException {
Product product = readProduct();
OrderItem orderItem = this.currentOrder.getItem(product);
if (orderItem != null) {
this.currentOrder.removeItem(orderItem);
stdOut.println("The product " + product.getCode()
+ " has been removed from the current order");
} else {
stdErr.println(
"There are no products in the current order with that code");
}
}
/**
* Registers the sale of the current order.
*/
public void saleOrder() {
if (this.currentOrder.getNumberOfItems() > 0) {
this.sales.addOrder(this.currentOrder);
this.currentOrder = new Order();
stdOut.println("The sale of the order has been registered");
} else {
stdErr.println("The current order is empty");
}
}
/**
* Displays the orders that have been sold.
*/
public void displayOrdersSold() {
int numOrders = this.sales.getNumberOfOrders();
if (numOrders != 0) {
int orderNumber = 1;
for (Order order : this.sales) {
stdOut.println("Order " + orderNumber++);
for (OrderItem orderItem : order) {
stdOut.println(" " + orderItem.toString());
}
stdOut.println(" Total: " +
CURRENCY.format(order.getTotalCost()));
}
} else {
stdErr.println("There are no sales");
}
}
/**
* Displays the number of orders that contain a specified product
*
* @param product the <code>Product</code> object to be displayed.
*/
public void displayNumberOfOrders(Product product) {
/* PLACE YOUR CODE HERE */
int numbers=0;
for(Order order:sales) {
if(order.getItem(product)!=null) {
numbers++;
}
}
System.out.println("Number of orders that contains the product "+product.getCode()+": "+numbers);
}
/**
* Displays the total quantity of product that have has sold for each
* product in the catalog.
*/
public void displayTotalQuantityOfProducts() {
/* PLACE YOUR CODE HERE */
for(Product product:catalog) {
int numbers=0;
for(Order order:this.sales) {
if(order.getItem(product)!=null) {
numbers+=order.getItem(product).getQuantity();
}
}
System.out.println(product.getCode()+" "+numbers);
}
}
/*
* Prompts user for a product code and locates the associated
* <code>Product</code> object.
*
* @return reference to the <code>Product</code> object with
* the specified code
*/
private Product readProduct() throws IOException {
do {
stdErr.print("Product code> ");
stdErr.flush();
Product product = this.catalog.getProduct(stdIn.readLine());
//product=catalog.getProduct("A001");
if (product != null) {
return product;
} else {
stdErr.println("There are no products with that code");
}
} while (true);
}
/*
* Prompts user for the product quantity and verifies the
* user's response.
*
* @return a positive integer
*/
private int readQuantity() throws IOException {
int quantity;
do {
try {
stdErr.print("Quantity> ");
stdErr.flush();
quantity = Integer.parseInt(stdIn.readLine());
if (quantity > 0) {
return quantity;
} else {
stdErr.println(
"Invalid input. Please enter a positive integer");
}
} catch (NumberFormatException nfe) {
stdErr.println(nfe);
}
} while (true);
}
}
运行结果见上图，谢谢大家
