class ShoppingCart {

private int itemCount = 0; // 购物车中的商品数量

// 向购物车添加商品

public synchronized void addItem() {

itemCount++;

System.out.println("Item added. Total items in cart: " + itemCount);

}

// 从购物车移除商品

public synchronized void removeItem() {

if (itemCount > 0) {

itemCount--;

System.out.println("Item removed. Total items in cart: " + itemCount);

} else {

System.out.println("No items to remove.");

}

}

// 显示购物车状态

public synchronized void displayCart() {

System.out.println("Shopping Cart contains " + itemCount + " items.");

}

}

class Shopper implements Runnable {

private ShoppingCart cart;

private int addOperations;

private int removeOperations;

public Shopper(ShoppingCart cart, int addOperations, int removeOperations) {

this.cart = cart;

this.addOperations = addOperations;

this.removeOperations = removeOperations;

}

@Override

public void run() {

for (int i = 0; i < addOperations; i++) {

cart.addItem();

}

for (int i = 0; i < removeOperations; i++) {

cart.removeItem();

}

}

}

public class ShoppingCartSystem {

public static void main(String[] args) {

ShoppingCart cart = new ShoppingCart();

// 创建多个购物者线程

Thread shopper1 = new Thread(new Shopper(cart, 5, 3));

Thread shopper2 = new Thread(new Shopper(cart, 3, 2));

shopper1.start();

shopper2.start();

}

}