sentinel @SentinelResource 异常处理

1、过程

若SentinelRescourse中有 blockHandler，则调用blockHandler指定的方法进行兜底回调

否则进行全局异常处理

2、blockHandler 指定兜底回调方法

@SentinelResource(value = "createOrder", blockHandler = "createOrderFallBack")

createOrderFallBack 兜底回调方法

3、兜底回调方法

注意

a、兜底方法必须createOrderFallBack与原方法createOrder参数列表完全一致

b、兜底方法必须返回相同类型或兼容类型

c、兜底方法必须位于同一个类中（除非使用 blockHandlerClass 指定）

// 兜底回调
public Order createOrderFallBack(Long userId, Long productId, BlockException e){
    Order order = new Order();
    order.setId(0L);
    order.setTotalAmount(new BigDecimal("0"));
    order.setUserId(userId);
    order.setNickName("未知的");
    order.setAddress("异常信息："+e.getClass());
    order.setProductList(null);
    return order;
}

4、整体

package com.wt.order.service.impl;
import com.alibaba.csp.sentinel.slots.block.BlockException;
import java.math.BigDecimal;
import java.util.Arrays;
import java.util.List;

import com.alibaba.csp.sentinel.annotation.SentinelResource;
import com.wt.order.bean.Order;
import com.wt.order.feign.ProductFeignClient;
import com.wt.order.service.OrderService;
import com.wt.product.bean.Product;
import lombok.extern.slf4j.Slf4j;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.cloud.client.ServiceInstance;
import org.springframework.cloud.client.discovery.DiscoveryClient;
import org.springframework.cloud.client.loadbalancer.LoadBalancerClient;
import org.springframework.stereotype.Component;
import org.springframework.stereotype.Service;
import org.springframework.web.client.RestTemplate;

/**
 * @Description: TODO
 * @Author: 1872428
 * @Date: 2025/6/7 8:51
 * @Version: 1.0
 **/
@Service
@Slf4j
public class OrderServiceImpl implements OrderService {

    @Autowired
    private ProductFeignClient productFeignClient;

    @SentinelResource(value = "createOrder", blockHandler = "createOrderFallBack")
    @Override
    public Order createOrder(Long userId, Long productId) {
        //Product product = getProductRemoteAnno(productId);
        Product product = productFeignClient.getProductById(productId);
        Order order = new Order();
        order.setId(1L);
        // 价格
        order.setTotalAmount(product.getPrice().multiply(new BigDecimal(product.getNum())));
        order.setUserId(userId);
        order.setNickName("lisi");
        order.setAddress("徐州");
        // 商品列表
        order.setProductList(Arrays.asList(product));

        return order;
    }

    // 兜底回调
    public Order createOrderFallBack(Long userId, Long productId, BlockException e){
        Order order = new Order();
        order.setId(0L);
        order.setTotalAmount(new BigDecimal("0"));
        order.setUserId(userId);
        order.setNickName("未知的");
        order.setAddress("异常信息："+e.getClass());
        order.setProductList(null);
        return order;
    }
}