im/src/main/java/com/example/course/config/RedisConfig.java

package com.example.course.config;

import com.fasterxml.jackson.annotation.JsonTypeInfo;
import com.fasterxml.jackson.databind.ObjectMapper;
import com.fasterxml.jackson.databind.SerializationFeature;
import com.fasterxml.jackson.datatype.jsr310.JavaTimeModule;
import org.springframework.context.annotation.Bean;
import org.springframework.data.redis.connection.RedisConnectionFactory;
import org.springframework.data.redis.core.RedisTemplate;
import org.springframework.data.redis.serializer.GenericJackson2JsonRedisSerializer;
import org.springframework.data.redis.serializer.StringRedisSerializer;
import org.springframework.stereotype.Component;

import java.text.SimpleDateFormat;

@Component
public class RedisConfig {

    @Bean
    public RedisTemplate<String, Object> redisTemplate(RedisConnectionFactory connectionFactory) {
        RedisTemplate<String, Object> redisTemplate = new RedisTemplate<>();
        redisTemplate.setConnectionFactory(connectionFactory);

        // Key/HashKey 使用字符串序列化
        StringRedisSerializer stringSerializer = new StringRedisSerializer();
        redisTemplate.setKeySerializer(stringSerializer);
        redisTemplate.setHashKeySerializer(stringSerializer);

        // Value/HashValue 使用 JSON 序列化（带类型信息）
        GenericJackson2JsonRedisSerializer jsonSerializer = createJsonSerializer();
        redisTemplate.setValueSerializer(jsonSerializer);
        redisTemplate.setHashValueSerializer(jsonSerializer);

        redisTemplate.afterPropertiesSet();
        return redisTemplate;
    }

    /**
     * 创建支持类型信息的 JSON 序列化器
     */
    private GenericJackson2JsonRedisSerializer createJsonSerializer() {
        ObjectMapper objectMapper = new ObjectMapper();

        // 启用默认类型信息（解决嵌套对象反序列化问题）
        objectMapper.activateDefaultTyping(
                objectMapper.getPolymorphicTypeValidator(),
                ObjectMapper.DefaultTyping.NON_FINAL,
                JsonTypeInfo.As.PROPERTY
        );

        // 配置日期格式（根据实际需求调整）
        objectMapper.disable(SerializationFeature.WRITE_DATES_AS_TIMESTAMPS);
        objectMapper.registerModule(new JavaTimeModule());
        objectMapper.setDateFormat(new SimpleDateFormat("yyyy-MM-dd HH:mm:ss"));
        return new GenericJackson2JsonRedisSerializer(objectMapper);
    }
}