java输入购物清单，包括商品名数量单价，输出每样商品金额，输入折扣，计算最终金额找零并输出

在Java中，你可以创建一个更交互式的程序来接收用户的输入，包括商品名、数量和单价，然后计算每件商品的金额，接着获取折扣率，计算最终总金额并找出找零。这里是一个简单的例子，使用Scanner类来读取用户输入：

import java.util.Scanner;

class Product {
    String name;
    int quantity;
    double unitPrice;

    public Product(String name, int quantity, double unitPrice) {
        this.name = name;
        this.quantity = quantity;
        this.unitPrice = unitPrice;
    }

    public double getTotalCost() {
        return quantity * unitPrice;
    }

    @Override
    public String toString() {
        return name + ": " + quantity + " x $" + unitPrice + ", 总价: $" + getTotalCost();
    }
}

class DiscountCalculator {
    private Scanner scanner;
    private double totalCost;
    private double discountRate;

    public DiscountCalculator() {
        scanner = new Scanner(System.in);
    }

    public void inputProducts() {
        System.out.println("请输入商品信息（按q退出）:");
        while (scanner.hasNext()) {
            String input = scanner.nextLine();
            if (input.equalsIgnoreCase("q")) break;
            String[] parts = input.split(",");
            String name = parts[0];
            int quantity = Integer.parseInt(parts[1]);
            double unitPrice = Double.parseDouble(parts[2]);
            Product product = new Product(name, quantity, unitPrice);
            totalCost += product.getTotalCost();
            System.out.println(product);
        }
    }

    public void inputDiscount() {
        System.out.println("请输入折扣率（百分比形式）:");
        discountRate = scanner.nextDouble();
    }

    public double calculateFinalCostAndChange() {
        double discountedTotal = totalCost * (1 - discountRate / 100);
        double change = Math.abs(discountedTotal - totalCost);
        System.out.printf("折扣后的总价: $%.2f, 找零: $%.2f\n", discountedTotal, change);
        return discountedTotal;
    }

    public static void main(String[] args) {
        DiscountCalculator calculator = new DiscountCalculator();
        calculator.inputProducts();
        calculator.inputDiscount();
        calculator.calculateFinalCostAndChange();
    }
}

在这个例子中，用户输入商品信息直到选择退出，然后输入折扣率，最后计算并显示最终费用及找零。