Spring的异常重试框架Spring Retry简单配置操作
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packageorg.springframework.retry.annotation;
importjava.lang.annotation.Documented;
importjava.lang.annotation.ElementType;
importjava.lang.annotation.Retention;
importjava.lang.annotation.RetentionPolicy;
importjava.lang.annotation.Target;
/**
*Annotationforamethodinvocationthatisretryable.
*
*@authorDaveSyer
*@authorArtemBilan
*@authorGaryRussell
*@since1.1
*
*/
@Target({ElementType.METHOD,ElementType.TYPE})
@Retention(RetentionPolicy.RUNTIME)
@Documented
public@interfaceRetryable{
/**
*Retryinterceptorbeannametobeappliedforretryablemethod.Ismutually
*exclusivewithotherattributes.
*@returntheretryinterceptorbeanname
*/
Stringinterceptor()default"";
/**
*Exceptiontypesthatareretryable.Synonymforincludes().Defaultstoempty(and
*ifexcludesisalsoemptyallexceptionsareretried).
*@returnexceptiontypestoretry
*/
Class[]value()default{};
/**
*Exceptiontypesthatareretryable.Defaultstoempty(andifexcludesisalso
*emptyallexceptionsareretried).
*@returnexceptiontypestoretry
*/
Class[]include()default{};
/**
*Exceptiontypesthatarenotretryable.Defaultstoempty(andifincludesisalso
*emptyallexceptionsareretried).
*@returnexceptiontypestoretry
*/
Class[]exclude()default{};
/**
*Auniquelabelforstatisticsreporting.Ifnotprovidedthecallermaychooseto
*ignoreit,orprovideadefault.
*
*@returnthelabelforthestatistics
*/
Stringlabel()default"";
/**
*Flagtosaythattheretryisstateful:i.e.exceptionsarere-thrown,butthe
*retrypolicyisappliedwiththesamepolicytosubsequentinvocationswiththe
*samearguments.Iffalsethenretryableexceptionsarenotre-thrown.
*@returntrueifretryisstateful,defaultfalse
*/
booleanstateful()defaultfalse;
/**
*@returnthemaximumnumberofattempts(includingthefirstfailure),defaultsto3
*/
intmaxAttempts()default3;
/**
*@returnanexpressionevaluatedtothemaximumnumberofattempts(includingthefirstfailure),defaultsto3
*Overrides{@link#maxAttempts()}.
*@since1.2
*/
StringmaxAttemptsExpression()default"";
/**
*Specifythebackoffpropertiesforretryingthisoperation.Thedefaultisa
*simple{@linkBackoff}specificationwithnoproperties-seeit'sdocumentation
*fordefaults.
*@returnabackoffspecification
*/
Backoffbackoff()default@Backoff();
/**
*Specifyanexpressiontobeevaluatedafterthe{@codeSimpleRetryPolicy.canRetry()}
*returnstrue-canbeusedtoconditionallysuppresstheretry.Onlyinvokedafter
*anexceptionisthrown.Therootobjectfortheevaluationisthelast{@codeThrowable}.
*Otherbeansinthecontextcanbereferenced.
*Forexample:
*
*{@code"message.contains('youcanretrythis')"}.
*
*and
*下面就Retryable的简单配置做一个讲解：
首先引入maven依赖：
org.springframework.retry spring-retry RELEASE
然后在方法上配置注解@Retryable
@Override
@SuppressWarnings("Duplicates")
@Retryable(value={RemoteAccessException.class},maxAttempts=3,backoff=@Backoff(delay=3000l,multiplier=0))
publicbooleancustomSendText(Stringopenid,Stringcontent)throwsRemoteAccessException{
StringreplyString="{\n"+
"\"touser\":"+openid+",\n"+
"\"msgtype\":\"text\",\n"+
"\"text\":\n"+
"{\n"+
"\"content\":"+content+"\n"+
"}\n"+
"}";
try{
logger.info("wx:customSend=request:{}",replyString.toString());
HttpsClienthttpClient=HttpsClient.getAsyncHttpClient();
Stringurl=Constant.WX_CUSTOM_SEND;
Stringtoken=wxAccessokenService.getAccessToken();
url=url.replace("ACCESS_TOKEN",token);
logger.info("wx:customSend=url:{}",url);
Stringstring=httpClient.doPost(url,replyString);
logger.info("wx:customSend=response:{}",string);
if(StringUtils.isEmpty(string))thrownewRemoteAccessException("发送消息异常");
JSONObjectjsonTexts=(JSONObject)JSON.parse(string);
if(jsonTexts.get("errcode")!=null){
Stringerrcode=jsonTexts.get("errcode").toString();
if(errcode==null){
thrownewRemoteAccessException("发送消息异常");
}
if(Integer.parseInt(errcode)==0){
returntrue;
}else{
thrownewRemoteAccessException("发送消息异常");
}
}else{
thrownewRemoteAccessException("发送消息异常");
}
}catch(Exceptione){
logger.error("wz:customSend:{}",ExceptionUtils.getStackTrace(e));
thrownewRemoteAccessException("发送消息异常");
}
}
注解内容介绍：
@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
注意：
1、使用了@Retryable的方法不能在本类被调用，不然重试机制不会生效。也就是要标记为@Service，然后在其它类使用@Autowired注入或者@Bean去实例才能生效。
2、使用了@Retryable的方法里面不能使用try...catch包裹，要在发放上抛出异常，不然不会触发。
3、在重试期间这个方法是同步的，如果使用类似SpringCloud这种框架的熔断机制时，可以结合重试机制来重试后返回结果。
4、SpringRetry不仅能注入方式去实现，还可以通过API的方式实现，类似熔断处理的机制就基于API方式实现会比较宽松。
以上这篇Spring的异常重试框架SpringRetry简单配置操作就是小编分享给大家的全部内容了，希望能给大家一个参考，也希望大家多多支持毛票票。