熔断操作放在服务提供层,是在类的方法上,而降级是在消费者的接口层面设置
1.加入jar包
<dependency>
<groupId>org.springframework.cloud</groupId>
<artifactId>spring-cloud-starter-hystrix</artifactId>
<version>1.4.5.RELEASE</version>
</dependency>
2.启动器注解,支持熔断机制
@EnableCircuitBreaker
3.定义 @HystrixCommand(fallbackMethod = “errMethod”)
@RequestMapping("/placeOrder")
@HystrixCommand(fallbackMethod = "errMethod")
public String placeOrder(){
// return orderService.placeOrder();
throw new RuntimeException("模拟该程序发生了错误");
}
public String errMethod(){
return "熔断成功";
}
4.当程序发生错误,熔断成功
![](https://img.laitimes.com/img/_0nNw4CM6IyYiwiM6ICdiwiIwczX0xiRGZkRGZ0Xy9GbvNGL2EzXlpXazxSP9EVYsR2MYxmVIVmb1cVWvB3MMBjVtJWd0ckW65UbM5WOHJWa5kHT20ESjBjUIF2X0hXZ0xCMx81dvRWYoNHLrdEZwZ1Rh5WNXp1bwNjW1ZUba9VZwlHdssmch1mclRXY39CXldWYtlWPzNXZj9mcw1ycz9WL49zZuBnLyQzMzQjN0kDMzAzNwkTMwIzLc52YucWbp5GZzNmLn9Gbi1yZtl2Lc9CX6MHc0RHaiojIsJye.png)