org.springframework.cache.interceptor.SimpleKey cannot be cast to java.lang.String

springboot整合redis时，使用@Cacheable注解，如果方法的key参数为空，就会报org.springframework.cache.interceptor.SimpleKey cannot be cast to java.lang.String的错误。

? 1 错误信息

? 2 如图

? 3 解决方案

package com.test.config;

import org.springframework.cache.CacheManager;
import org.springframework.cache.annotation.CachingConfigurerSupport;
import org.springframework.cache.annotation.EnableCaching;
import org.springframework.cache.interceptor.KeyGenerator;
import org.springframework.context.annotation.Bean;
import org.springframework.context.annotation.Configuration;
import org.springframework.data.redis.cache.RedisCacheManager;
import org.springframework.data.redis.core.RedisTemplate;

/**
 * Created by toutou on 2019/3/9.
 */
@Configuration
@EnableCaching
public class RedisCacheConfig extends CachingConfigurerSupport {

    @Override
    @Bean
    public KeyGenerator keyGenerator() {
        return (target, method, params) -> {
            StringBuilder sb = new StringBuilder();
            sb.append(target.getClass().getName());
            sb.append(method.getName());
            for (Object obj : params) {
                sb.append(obj.toString());
            }
            return sb.toString();
        };
    }

    @Bean
    public CacheManager cacheManager(RedisTemplate redisTemplate) {
        RedisCacheManager cacheManager = new RedisCacheManager(redisTemplate);
        // 设置默认过期时间为60秒
        cacheManager.setDefaultExpiration(60);
        return cacheManager;
    }
}

原文地址：https://www.cnblogs.com/toutou/p/10516440.html