mongodb 的 MongoWaitQueueFullException

MongoWaitQueueFullException：MongoDB 等待队列已满异常

java
import com.mongodb.MongoClient;
import com.mongodb.MongoException;
import com.mongodb.client.MongoDatabase;
import org.bson.Document;
public class OrderService {
    private MongoClient mongoClient;
    private MongoDatabase database;
    public OrderService() {
        mongoClient = new MongoClient("localhost", 27017);
        database = mongoClient.getDatabase("ecommerce");
    }
    public void placeOrder(Document order) {
        try {
            database.getCollection("orders").insertOne(order);
            System.out.println("订单插入成功！");
        } catch (MongoException e) {
            if (e instanceof com.mongodb.MongoWaitQueueFullException) {
                System.out.println("等待队列已满，请稍后重试！");
            } else {
                System.out.println("订单插入失败！");
            }
        }
    }
    public static void main(String[] args) {
        OrderService orderService = new OrderService();
        Document order = new Document("order_id", "123456")
                .append("customer_id", "789")
                .append("total_amount", 99.99);
        orderService.placeOrder(order);
    }
}