Question

我有这段代码

@Retryable(maxAttempts = 3, stateful = true, include = ServiceUnavailableException.class,
        exclude = URISyntaxException.class, backoff = @Backoff(delay = 1000, multiplier = 2) )
public void testThatService(String serviceAccountId)
        throws ServiceUnavailableException, URISyntaxException {

//这里有一些实现 }

有没有办法可以使用@Value配置maxAttempts，延迟和乘数？或者是否有其他方法可以使注释中的这些字段可配置？

Answer 1

随着Spring-retry 1.2版的发布，它是可能的。可以使用SPEL配置@Retryable。

@Retryable(
    value = { SomeException.class,AnotherException.class },
    maxAttemptsExpression = "#{@myBean.getMyProperties('retryCount')}",
    backoff = @Backoff(delayExpression = "#{@myBean.getMyProperties('retryInitalInterval')}"))
public void doJob(){
    //your code here
}

有关详细信息，请参阅：https://github.com/spring-projects/spring-retry/blob/master/README.md

Answer 2

如果您想提供一个默认值，然后有选择地在application.properties文件中覆盖它：

@Retryable(maxAttemptsExpression = "#{${my.max.attempts:10}}")
public void myRetryableMethod() {
    // ...
}

Answer 3

目前不可能;要在属性中连接，必须更改注释以获取字符串值，并且注释bean后处理器必须解析占位符和/或SpEL表达式。

有关替代方案，请参阅this answer，但目前无法通过注释完成。

修改

<bean id="retryAdvice" class="org.springframework.retry.interceptor.RetryOperationsInterceptor"> <property name="retryOperations"> <bean class="org.springframework.retry.support.RetryTemplate"> <property name="retryPolicy"> <bean class="org.springframework.retry.policy.SimpleRetryPolicy"> <property name="maxAttempts" value="${max.attempts}" /> </bean> </property> <property name="backOffPolicy"> <bean class="org.springframework.retry.backoff.ExponentialBackOffPolicy"> <property name="initialInterval" value="${delay}" /> <property name="multiplier" value="${multiplier}" /> </bean> </property> </bean> </property> </bean> <aop:config> <aop:pointcut id="retries" expression="execution(* org..EchoService.test(..))" /> <aop:advisor pointcut-ref="retries" advice-ref="retryAdvice" order="-1" /> </aop:config>

EchoService.test是您要将重试应用于的方法。

Answer 4

您可以使用RetryTemplate bean代替@Retryable注释，如下所示：

@Value("${retry.max-attempts}")
private int maxAttempts;
@Value("${retry.delay}")
private long delay;

@Bean
public RetryTemplate retryTemplate() {
    SimpleRetryPolicy retryPolicy = new SimpleRetryPolicy();
    retryPolicy.setMaxAttempts(maxAttempts);

    FixedBackOffPolicy backOffPolicy = new FixedBackOffPolicy();
    backOffPolicy.setBackOffPeriod(delay);

    RetryTemplate template = new RetryTemplate();
    template.setRetryPolicy(retryPolicy);
    template.setBackOffPolicy(backOffPolicy);
    return template;
}

然后使用此模板的execute方法：

@Autowired
private RetryTemplate retryTemplate;

public ResponseVo doSomething(final Object data) {
    RetryCallback<ResponseVo, SomeException> retryCallback = new RetryCallback<ResponseVo, SomeException>() {
        @Override
        public ResponseVo doWithRetry(RetryContext context) throws SomeException {
             // do the business
             return responseVo;
        }
    };
    return retryTemplate.execute(retryCallback);
}

Answer 5

正如这里解释的那样： https://stackoverflow.com/a/43144064

1.2版引入了为某些属性使用表达式的功能。

所以你需要这样的东西：

@Retryable(maxAttempts = 3, stateful = true, include = ServiceUnavailableException.class,
        exclude = URISyntaxException.class, backoff = @Backoff(delayExpression = "#{${your.delay}}" , multiplier = 2) )
public void testThatService(String serviceAccountId)
        throws ServiceUnavailableException, URISyntaxException {

如何使spring @retryable可配置？

5 个答案: