如何利用Java实现仓库管理系统的库存统计功能

// 商品类
class Product {
    private String name;
    private double price;
    private int quantity;

    // 构造方法
    public Product(String name, double price, int quantity) {
        this.name = name;
        this.price = price;
        this.quantity = quantity;
    }

    // getter和setter方法
    // ...
}

// 入库类
class Inbound {
    private Product product;
    private Date date;
    private int quantity;

    // 构造方法
    public Inbound(Product product, Date date, int quantity) {
        this.product = product;
        this.date = date;
        this.quantity = quantity;
    }

    // getter和setter方法
    // ...
}

// 出库类
class Outbound {
    private Product product;
    private Date date;
    private int quantity;

    // 构造方法
    public Outbound(Product product, Date date, int quantity) {
        this.product = product;
        this.date = date;
        this.quantity = quantity;
    }

    // getter和setter方法
    // ...
}

// 仓库管理系统类
class WarehouseManagementSystem {
    private List<Product> productList;
    private List<Inbound> inboundList;
    private List<Outbound> outboundList;

    // 构造方法和其他方法
    // ...

    // 统计库存数量和金额
    public double calculateInventoryValue() {
        double value = 0;

        for (Product product : productList) {
            value += product.getPrice() * product.getQuantity();
        }

        return value;
    }

    // 统计进出库数量和金额
    public int calculateInboundQuantity(Date startDate, Date endDate) {
        int quantity = 0;

        for (Inbound inbound : inboundList) {
            if (inbound.getDate().after(startDate) && inbound.getDate().before(endDate)) {
                quantity += inbound.getQuantity();
            }
        }

        return quantity;
    }

    public int calculateOutboundQuantity(Date startDate, Date endDate) {
        int quantity = 0;

        for (Outbound outbound : outboundList) {
            if (outbound.getDate().after(startDate) && outbound.getDate().before(endDate)) {
                quantity += outbound.getQuantity();
            }
        }

        return quantity;
    }

    // 查询库存详情
    public List<Product> searchInventoryDetails() {
        return productList;
    }

    // 库存预警
    public List<Product> inventoryWarning(int threshold) {
        List<Product> warningList = new ArrayList<>();

        for (Product product : productList) {
            if (product.getQuantity() < threshold) {
                warningList.add(product);
            }
        }

        return warningList;
    }
}

// 主类
public class Main {
    public static void main(String[] args) {
        // 初始化数据
        Product product1 = new Product("商品1", 10.0, 100);
        Product product2 = new Product("商品2", 20.0, 200);

        List<Product> productList = new ArrayList<>();
        productList.add(product1);
        productList.add(product2);

        WarehouseManagementSystem warehouse = new WarehouseManagementSystem(productList, ...);

        // 调用库存统计功能
        double inventoryValue = warehouse.calculateInventoryValue();
        int inboundQuantity = warehouse.calculateInboundQuantity(startDate, endDate);
        int outboundQuantity = warehouse.calculateOutboundQuantity(startDate, endDate);
        List<Product> inventoryDetails = warehouse.searchInventoryDetails();
        List<Product > warningList = warehouse.inventoryWarning(50);

        // 显示结果
        // ...
    }
}