手把手教你Hystrix熔断技术

桃扇骨 2022-10-08 12:25 180阅读 0赞

**1、pom依赖：**

<dependency>
                <groupId>org.springframework.cloud</groupId>
                <artifactId>spring-cloud-starter-netflix-hystrix</artifactId>
                <version>2.2.1.RELEASE</version>
            </dependency>

注意SpringBoot和SpringCloud的版本要兼容

**2、在启动类上加上注解：`@EnableHystrix`**  
![在这里插入图片描述][watermark_type_ZmFuZ3poZW5naGVpdGk_shadow_10_text_aHR0cHM6Ly9ibG9nLmNzZG4ubmV0L3dlaXhpbl80Mjc0MDUzMA_size_16_color_FFFFFF_t_70]  
**3、在需要熔断的方法上加上注解：`@HystrixCommand(fallbackMethod = "方法名")`**

import com.netflix.hystrix.contrib.javanica.annotation.HystrixCommand;
    import org.springframework.web.bind.annotation.RequestMapping;
    import org.springframework.web.bind.annotation.RestController;
    
    @RestController
    public class HelloController {
    
    
        @RequestMapping("hello")
        @HystrixCommand(fallbackMethod = "fallBack")
        public String hello() throws InterruptedException {
            //制造异常来测试熔断，看是否执行熔断方法
            int i = 1 / 0;
            return "helloWorld!";
        }
    
        private String fallBack() {
            return "程序错误";
        }
        
    }

**4、访问**  
![在这里插入图片描述][watermark_type_ZmFuZ3poZW5naGVpdGk_shadow_10_text_aHR0cHM6Ly9ibG9nLmNzZG4ubmV0L3dlaXhpbl80Mjc0MDUzMA_size_16_color_FFFFFF_t_70 1]

**5、Hystrix默认超时时间**  
`Hystrix`默认`1秒`超时这个时间也是可以进行配置的：  
`application.yml`配置文件下：

#hystrix超时时间配置 （如果不配置的话默认是1000毫秒超时）
    hystrix:
      command:
        default:
          execution:
            isolation:
              thread:
                timeoutInMilliseconds: 3000

参考链接：https://www.cnblogs.com/haha12/p/11690489.html

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