本文介紹了Spring重試支持Spring Retry的方法，分享給大家，具體如下：
第一步、引入maven依賴
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<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
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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;@Servicepublic 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調(diào)用異常");}@Recoverpublic void recover(RemoteAccessException e) { System.out.println(e.getMessage());}} |
@Retryable注解
被注解的方法發(fā)生異常時(shí)會重試
value:指定發(fā)生的異常進(jìn)行重試
include:和value一樣，默認(rèn)空，當(dāng)exclude也為空時(shí)，所有異常都重試
exclude:指定異常不重試，默認(rèn)空，當(dāng)include也為空時(shí)，所有異常都重試
maxAttemps:重試次數(shù)，默認(rèn)3
backoff:重試補(bǔ)償機(jī)制，默認(rèn)沒有
@Backoff注解
delay:指定延遲后重試
multiplier:指定延遲的倍數(shù)，比如delay=5000l,multiplier=2時(shí)，第一次重試為5秒后，第二次為10秒，第三次為20秒
@Recover
當(dāng)重試到達(dá)指定次數(shù)時(shí)，被注解的方法將被回調(diào)，可以在該方法中進(jìn)行日志處理。需要注意的是發(fā)生的異常和入?yún)㈩愋鸵恢聲r(shí)才會回調(diào)
第三步、SpringBoot方式啟動容器、測試
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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@EnableRetrypublic class Application { public static void main(String[] args) throws Exception { ApplicationContext annotationContext = new AnnotationConfigApplicationContext("hello"); RemoteService remoteService = annotationContext.getBean("remoteService", RemoteService.class); remoteService.call(); }} |
運(yùn)行結(jié)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調(diào)用異常
參考 ：https://github.com/spring-projects/spring-retry
補(bǔ)充
對于非冪等的請求（比如新增，更新操作），千萬不要使用重試，對數(shù)據(jù)一致性會造成很大影響。
以上就是本文的全部內(nèi)容，希望對大家的學(xué)習(xí)有所幫助，也希望大家多多支持服務(wù)器之家。
原文鏈接：https://blog.csdn.net/u014513883/article/details/52371198
