springboot整合spring retry 重试机制 - HelloWorld开发者社区

当我们调用一个接口可能由于网络等原因造成第一次失败，再去尝试就成功了，这就是重试机制，spring支持重试机制，并且在Spring Cloud中可以与Hystaix结合使用，可以避免访问到已经不正常的实例。但是切记非幂等情况下慎用重试

一加入依赖

 <!-- 重试机制 -->
    <dependency>
      <groupId>org.springframework.retry</groupId>
      <artifactId>spring-retry</artifactId>
    </dependency>

    <dependency>
      <groupId>org.aspectj</groupId>
      <artifactId>aspectjweaver</artifactId>
    </dependency>

二在主类上加入 @EnableRetry 注解

@EnableRetry   //开启重试机制
@EnableAutoConfiguration //开启自动配置
@SpringBootApplication
public class WjKekingApplication {

  public static void main(String[] args) {
    SpringApplication.run(WjKekingApplication.class, args);
  }
}

三 demo

package com.wj.project.keking.myTest.service;

import org.slf4j.Logger;
import org.slf4j.LoggerFactory;
import org.springframework.retry.annotation.Backoff;
import org.springframework.retry.annotation.Recover;
import org.springframework.retry.annotation.Retryable;
import org.springframework.stereotype.Service;

import java.time.LocalTime;

@Service
public class RetryService {

    private final static Logger logger = LoggerFactory.getLogger(RetryService.class);

    private final int totalNum = 100000;

    /**
     * @Retryable的参数说明： •value：抛出指定异常才会重试
     * •include：和value一样，默认为空，当exclude也为空时，默认所以异常
     * •exclude：指定不处理的异常
     * •maxAttempts：最大重试次数，默认3次
     * •backoff：重试等待策略，默认使用@Backoff，@Backoff的value默认为1000L，我们设置为2000L；multiplier（指定延迟倍数）默认为0，表示固定暂停1秒后进行重试，如果把multiplier设置为1.5，则第一次重试为2秒，第二次为3秒，第三次为4.5秒。
     */
    @Retryable(value = Exception.class, maxAttempts = 3, backoff = @Backoff(delay = 2000L, multiplier = 1.5))
    public int retry(int num) {
        logger.info("减库存开始" + LocalTime.now());
        try {
            int i = 1 / 0;
        } catch (Exception e) {
            logger.error("illegal");
        }
        if (num <= 0) {
            throw new IllegalArgumentException("数量不对");
        }
        logger.info("减库存执行结束" + LocalTime.now());
        return totalNum - num;
    }

    @Recover
    public void recover(Exception e) {
        logger.warn("减库存失败！！！" + LocalTime.now());
    }


}

四写一个简单的测试

import base.BaseTest;
import org.junit.Test;
import org.springframework.beans.factory.annotation.Autowired;

public class RetryServiceTest extends BaseTest {

    @Autowired
    private RetryService retryService;

    @Test
    public void retry() {
        int count = retryService.retry(-1);
        System.out.println("库存为 ：" + count);
    }
}

五结果：

2018-07-28 01:12:09.836  INFO 31128 --- [           main] o.s.b.w.embedded.tomcat.TomcatWebServer  : Tomcat started on port(s): 55413 (http) with context path ''
2018-07-28 01:12:09.843  INFO 31128 --- [           main] c.w.p.k.myTest.service.RetryServiceTest  : Started RetryServiceTest in 7.178 seconds (JVM running for 10.657)
2018-07-28 01:12:10.584  INFO 31128 --- [           main] c.w.p.k.myTest.service.RetryService      : 减库存开始01:12:10.584
2018-07-28 01:12:10.584 ERROR 31128 --- [           main] c.w.p.k.myTest.service.RetryService      : illegal
2018-07-28 01:12:12.588  INFO 31128 --- [           main] c.w.p.k.myTest.service.RetryService      : 减库存开始01:12:12.588
2018-07-28 01:12:12.588 ERROR 31128 --- [           main] c.w.p.k.myTest.service.RetryService      : illegal
2018-07-28 01:12:15.588  INFO 31128 --- [           main] c.w.p.k.myTest.service.RetryService      : 减库存开始01:12:15.588
2018-07-28 01:12:15.588 ERROR 31128 --- [           main] c.w.p.k.myTest.service.RetryService      : illegal
2018-07-28 01:12:15.589  WARN 31128 --- [           main] c.w.p.k.myTest.service.RetryService      : 减库存失败！！！01:12:15.589
库存为 ：100000
2018-07-28 01:12:15.604  INFO 31128 --- [       Thread-3] ConfigServletWebServerApplicationContext : Closing org.springframework.boot.web.servlet.context.AnnotationConfigServletWebServerApplicationContext@1af2d44a: startup date [Sat Jul 28 01:12:03 CST 2018]; root of context hierarchy
2018-07-28 01:12:15.608  INFO 31128 --- [       Thread-3] o.s.s.concurrent.ThreadPoolTaskExecutor  : Shutting down ExecutorService 'taskExecutor'
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