SpringBoot解决LocalDateTime_cannot deserialize value of type `java.time.locald

项目场景：开发问题记录

例如： 前端传入时间报错，无法反序列化。向前端返回时间需要格式化

问题描述

前端传入的时间无法反序列化，向前端返回格式化时间

Cannot deserialize value of type `java.time.LocalDateTime` from String "2023-04-06 14:33:33": Failed to deserialize java.time.LocalDateTime: (java.time.format.DateTimeParseException) Text '2023-04-06 14:33:33' could not be parsed at index 10
 at [Source: (org.glassfish.jersey.message.internal.ReaderInterceptorExecutor$UnCloseableInputStream); line: 4, column: 18] (through reference chain: com.taiji.businessdomain.stmbsscpacdc.client.api.dto.persist.PersistExpressInfoRequest["updatedAt"])

 Cannot deserialize value of type `java.time.LocalDateTime` from String "2023-04-06 14:33:33": Failed to deserialize java.time.LocalDateTime: (java.time.format.DateTimeParseException) Text '2023-04-06 14:33:33' could not be parsed at index 10
 at [Source: (org.glassfish.jersey.message.internal.ReaderInterceptorExecutor$UnCloseableInputStream); line: 4, column: 18] (through reference chain: com.taiji.businessdomain.stmbsscpacdc.client.api.dto.persist.PersistExpressInfoRequest["updatedAt"])

原因分析：

提示：这里填写问题的分析：

时间格式导致无法反序列化，前端时间默认格式一般为“2023-04-06T14:33:14.997Z”，而"2023-04-06 14:33:33"这种时间格式化无法接收

解决方案1：

提示：这里填写该问题的具体解决方案：

直接在属性上加上注解

@JsonFormat(shape=JsonFormat.Shape.STRING, pattern = "yyyy-MM-dd HH:mm:ss")

解决方案2：

提示：这里填写该问题的具体解决方案：

通过jackson来自定义一个全局类型处理，通过序列化可以将返回前端的时间进行格式化，反序列化将前端传来的时间进行格式化

package com.taiji.config;
 
import com.fasterxml.jackson.core.JsonParser;
import com.fasterxml.jackson.databind.DeserializationContext;
import com.fasterxml.jackson.databind.JsonDeserializer;
import com.fasterxml.jackson.datatype.jsr310.ser.LocalDateTimeSerializer;
import org.springframework.boot.autoconfigure.jackson.Jackson2ObjectMapperBuilderCustomizer;
import org.springframework.context.annotation.Bean;
import org.springframework.context.annotation.Configuration;
import java.io.IOException;
import java.time.Instant;
import java.time.LocalDateTime;
import java.time.ZoneId;
import java.time.format.DateTimeFormatter;
 
@Configuration
public class LocalDateTimeSerializerConfig {
 
    @Bean
    public Jackson2ObjectMapperBuilderCustomizer jackson2ObjectMapperBuilderCustomizer() {
        return builder -> {
            //序列化
            builder.serializerByType(LocalDateTime.class, new LocalDateTimeSerializer(DateTimeFormatter.ofPattern("yyyy-MM-dd HH:mm:ss")));
            //反序列化
            builder.deserializerByType(LocalDateTime.class, new LocalDateTimeDeserializer());
        };
    }
 
    /**
     * 反序列化
     */
        public static class LocalDateTimeDeserializer extends JsonDeserializer<LocalDateTime> {
        @Override
        public LocalDateTime deserialize(JsonParser p, DeserializationContext deserializationContext)
                throws IOException {
            long timestamp = p.getValueAsLong();
            if (timestamp > 0) {
                return LocalDateTime.ofInstant(Instant.ofEpochMilli(timestamp), ZoneId.systemDefault());
            } else {
                return null;
            }
        }
    }
 
}