springretry

package com.example.demo.springretry;

import org.springframework.context.annotation.Configuration;
import org.springframework.retry.annotation.EnableRetry;

@EnableRetry
@Configuration
public class RetryConfiguration {


}

package com.example.demo.springretry;

import lombok.extern.slf4j.Slf4j;
import org.springframework.retry.annotation.Backoff;
import org.springframework.retry.annotation.Recover;
import org.springframework.retry.annotation.Retryable;
import org.springframework.stereotype.Service;

@Service
@Slf4j
public class RetryService {

    /**
     * @Retryable注解:
     * 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；multiplier（指定延迟倍数）
     */
    @Retryable(value = Exception.class, maxAttempts = 3, backoff = @Backoff(delay = 2000L, multiplier = 2))
    public void devide(double a, double b){
        log.info("开始进行除法运算");
        if (b == 0) {
            throw new RuntimeException();
        }
        log.info("{} / {} = {}", a, b, a / b);
    }

    /**
     * @Recover注解：
     * 当重试达到指定次数时候该注解的方法将被回调
     * 发生的异常类型需要和@Recover注解的参数一致
     * @Retryable注解的方法不能有返回值，不然@Recover注解的方法无效
     */
    @Recover
    public void recover() {
        log.error("被除数不能为0");
    }


}