在spring boot中为想要的类进行，序列化||反序列化

自定义自己的序列化||反序列化器

//以LocalDateTime为例

/*
 *序列化器
 *必须要继承JsonSerializer<T>
 */
@Component
public class LocalDateTimeSerializer extends JsonSerializer<LocalDateTime> {

    @Override
    public void serialize(LocalDateTime localDateTime, JsonGenerator jsonGenerator, SerializerProvider serializerProvider) throws IOException {
        //将localDateTime序列化为时间戳
        jsonGenerator.writeNumber(localDateTime.toInstant(ZoneOffset.ofHours(8)).toEpochMilli());
    }

    @Override
    public Class<LocalDateTime> handledType() {
        return LocalDateTime.class;
    }
}

/*
 *反序列化器
 *必须要继承JsonDeserializer<T>
 */
@Component
public class LocalDateTimeDeserializer extends JsonDeserializer<LocalDateTime> {

    @Override
    public LocalDateTime deserialize(JsonParser jsonParser, DeserializationContext deserializationContext) throws IOException {
        //获取时间戳
        long timestamp = jsonParser.getLongValue();
        //将时间戳反序列化为localDateTime
        return LocalDateTime.ofEpochSecond(timestamp / 1000, 0, ZoneOffset.ofHours(8));
    }

    @Override
    public Class<LocalDateTime> handledType() {
        return LocalDateTime.class;
    }
}

在spring boot接管MVC的类中进行配置自己的序列化||反序列化器

@Configuration
//@EnableWebMvc，全面接管springMVC，建议菜鸡不要用
public class MySpringMVConfig implements WebMvcConfigurer {
    
    //装配自己的localDateTime序列化器
    @Autowired
    private LocalDateTimeSerializer localDateTimeSerializer;
    //装配自己的localDateTime反序列化器
    @Autowired
    private LocalDateTimeDeserializer localDateTimeDeserializer;


    /**
     * 配置 Jackson
     *
     * @param converters 消息转换器
     */
    @Override
    public void configureMessageConverters(List<HttpMessageConverter<?>> converters) {
        ObjectMapper objectMapper = Jackson2ObjectMapperBuilder
                .json()
                // 属性为 null 时不进行序列化
                .serializationInclusion(JsonInclude.Include.NON_NULL)
                // 指定 LocalDateTime 序列化器
                .serializers(localDateTimeSerializer)
                // 指定 LocalDateTime 反序列化器
                .deserializers(localDateTimeDeserializer)
                .build();

        StringHttpMessageConverter stringHttpMessageConverter = new StringHttpMessageConverter(StandardCharsets.UTF_8);

        converters.add(new MappingJackson2HttpMessageConverter(objectMapper));
        converters.add(stringHttpMessageConverter);
    }
}