Redis反序列化LocalDateTime时报错

报错信息

Caused by: com.fasterxml.jackson.databind.exc.InvalidDefinitionException: Cannot construct instance of `java.time.LocalDateTime` (no Creators, like default construct, exist): cannot deserialize from Object value (no delegate- or property-based Creator)

查看后发现是数据从redis中取出时，Jackson2反序列化数据处理LocalDateTime类型时出错，原因是：Jackson2在序列化LocalDateTime时输出的不是普通的字符串时间格式，而是如下所示的格式（普通时间格式：2019-02-27 12:10:17）。

"registeredTime": {
    "nano": 251128500,
    "year": 2020,
    "monthValue": 2,
    "dayOfMonth": 15,
    "hour": 16,
    "minute": 17,
    "second": 2,
    "month": "FEBRUARY",
    "dayOfWeek": "SATURDAY",
    "dayOfYear": 46,
    "chronology": {
      "@class": "java.time.chrono.IsoChronology",
      "id": "ISO",
      "calendarType": "iso8601"
    }
  }

所以是Jackson2序列化LocalDateTime跟我们所预想的不一致，将注册给redis的序列化模板修改成以下就行。

import com.example.redis.pojo.User;
import com.fasterxml.jackson.annotation.JsonAutoDetect;
import com.fasterxml.jackson.annotation.JsonTypeInfo;
import com.fasterxml.jackson.annotation.PropertyAccessor;
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.context.annotation.Configuration;
import org.springframework.data.redis.connection.jedis.JedisConnectionFactory;
import org.springframework.data.redis.connection.lettuce.LettuceConnectionFactory;
import org.springframework.data.redis.core.RedisTemplate;
import org.springframework.data.redis.serializer.GenericJackson2JsonRedisSerializer;
import org.springframework.data.redis.serializer.Jackson2JsonRedisSerializer;
import org.springframework.data.redis.serializer.StringRedisSerializer;
import java.io.Serializable;

@Configuration
public class RedisConfig {

    @Bean
    public RedisTemplate<String, Serializable> redisTemplate(LettuceConnectionFactory connectionFactory) {
        RedisTemplate<String, Serializable> redisTemplate = new RedisTemplate<>();
        redisTemplate.setKeySerializer(new StringRedisSerializer());
        //redisTemplate.setValueSerializer(new GenericJackson2JsonRedisSerializer());
        redisTemplate.setConnectionFactory(connectionFactory);
        //redisTemplate.setConnectionFactory(new JedisConnectionFactory());

        //下面代码解决LocalDateTime序列化与反序列化不一致问题
        Jackson2JsonRedisSerializer<Object> j2jrs = new Jackson2JsonRedisSerializer<>(Object.class);
        ObjectMapper om = new ObjectMapper();
        om.setVisibility(PropertyAccessor.ALL, JsonAutoDetect.Visibility.ANY);
        // 解决jackson2无法反序列化LocalDateTime的问题
        om.disable(SerializationFeature.WRITE_DATES_AS_TIMESTAMPS);
        om.registerModule(new JavaTimeModule());
        om.enableDefaultTyping(ObjectMapper.DefaultTyping.NON_FINAL, JsonTypeInfo.As.PROPERTY);
        j2jrs.setObjectMapper(om);
        // 序列化 value 时使用此序列化方法
        redisTemplate.setValueSerializer(j2jrs);
        redisTemplate.setHashValueSerializer(j2jrs);

        return redisTemplate;
    }

}

转载连接： https://www.cnblogs.com/quec1994/p/10452230.html