本文介绍了Spring重试支持Spring Retry的方法,分享给大家,具体如下:
第一步、引入maven依赖
<parent>
<groupId>org.springframework.boot</groupId>
<artifactId>spring-boot-starter-parent</artifactId>
<version>1.5.3.RELEASE</version>
</parent>
<dependency>
<groupId>org.springframework.boot</groupId>
<artifactId>spring-boot-starter-web</artifactId>
</dependency>
<!-- https://mvnrepository.com/artifact/org.springframework.retry/spring-retry -->
<dependency>
<groupId>org.springframework.retry</groupId>
<artifactId>spring-retry</artifactId>
<version>1.1.2.RELEASE</version>
</dependency>
<dependency>
<groupId>org.aspectj</groupId>
<artifactId>aspectjweaver</artifactId>
<version>1.8.6</version>
</dependency>
第二步、添加@Retryable和@Recover注解
package hello;
import org.springframework.remoting.RemoteAccessException;
import org.springframework.retry.annotation.Backoff;
import org.springframework.retry.annotation.Recover;
import org.springframework.retry.annotation.Retryable;
import org.springframework.stereotype.Service;
@Service
public class RemoteService {
@Retryable(value= {RemoteAccessException.class},maxAttempts = 3,backoff = @Backoff(delay = 5000l,multiplier = 1))
public void call() throws Exception {
System.out.println("do something...");
throw new RemoteAccessException("RPC调用异常");
}
@Recover
public void recover(RemoteAccessException e) {
System.out.println(e.getMessage());
}
}
@Retryable注解
被注解的方法发生异常时会重试
value:指定发生的异常进行重试
include:和value一样,默认空,当exclude也为空时,所有异常都重试
exclude:指定异常不重试,默认空,当include也为空时,所有异常都重试
maxAttemps:重试次数,默认3
backoff:重试补偿机制,默认没有
@Backoff注解
delay:指定延迟后重试
multiplier:指定延迟的倍数,比如delay=5000l,multiplier=2时,第一次重试为5秒后,第二次为10秒,第三次为20秒
@Recover
当重试到达指定次数时,被注解的方法将被回调,可以在该方法中进行日志处理。需要注意的是发生的异常和入参类型一致时才会回调
第三步、SpringBoot方式启动容器、测试
添加@EnableRetry注解,启用重试功能
package hello;
import org.springframework.boot.autoconfigure.SpringBootApplication;
import org.springframework.context.ApplicationContext;
import org.springframework.context.annotation.AnnotationConfigApplicationContext;
import org.springframework.retry.annotation.EnableRetry;
@SpringBootApplication
@EnableRetry
public class Application {
public static void main(String[] args) throws Exception {
ApplicationContext annotationContext = new AnnotationConfigApplicationContext("hello");
RemoteService remoteService = annotationContext.getBean("remoteService", RemoteService.class);
remoteService.call();
}
}
运行结果:
16:50:51.012 [main] DEBUG org.springframework.retry.support.RetryTemplate - Retry: count=0
do something…
16:50:51.025 [main] DEBUG org.springframework.retry.backoff.ExponentialBackOffPolicy - Sleeping for 5000
16:50:56.026 [main] DEBUG org.springframework.retry.support.RetryTemplate - Checking for rethrow: count=1
16:50:56.026 [main] DEBUG org.springframework.retry.support.RetryTemplate - Retry: count=1
do something…
16:50:56.026 [main] DEBUG org.springframework.retry.backoff.ExponentialBackOffPolicy - Sleeping for 5000
16:51:01.026 [main] DEBUG org.springframework.retry.support.RetryTemplate - Checking for rethrow: count=2
16:51:01.027 [main] DEBUG org.springframework.retry.support.RetryTemplate - Retry: count=2
do something…
16:51:01.027 [main] DEBUG org.springframework.retry.support.RetryTemplate - Checking for rethrow: count=3
16:51:01.027 [main] DEBUG org.springframework.retry.support.RetryTemplate - Retry failed last attempt: count=3
RPC调用异常
参考 :https://github.com/spring-projects/spring-retry
补充
对于非幂等的请求(比如新增,更新操作),千万不要使用重试,对数据一致性会造成很大影响。
以上就是本文的全部内容,希望对大家的学习有所帮助,也希望大家多多支持社区。 |