Java 解决long类型数据在前后端传递失真问题

问题：雪花算法的id长度为19位，前端能够接收的数字最多只能是16位的，因此就会造成精度丢失，得到的ID不是真正的ID。

解决：

在拦截器中加入Long类型转换，返回给前端string

package io.global.iot.common.config;

import com.fasterxml.jackson.annotation.JsonAutoDetect;
import com.fasterxml.jackson.annotation.PropertyAccessor;
import com.fasterxml.jackson.databind.ObjectMapper;
import com.fasterxml.jackson.databind.SerializationFeature;
import com.fasterxml.jackson.databind.ser.std.ToStringSerializer;
import com.fasterxml.jackson.datatype.jsr310.JavaTimeModule;
import com.fasterxml.jackson.datatype.jsr310.ser.LocalDateTimeSerializer;
import org.springframework.context.annotation.Configuration;
import org.springframework.http.converter.HttpMessageConverter;
import org.springframework.http.converter.json.MappingJackson2HttpMessageConverter;
import org.springframework.web.servlet.config.annotation.WebMvcConfigurer;

import java.time.LocalDateTime;
import java.time.format.DateTimeFormatter;
import java.util.List;

@Configuration
public class MvcConfiguration implements WebMvcConfigurer {

    @Override
    public void extendMessageConverters(List> converters) {
        MappingJackson2HttpMessageConverter messageConverter = new MappingJackson2HttpMessageConverter();
        ObjectMapper objectMapper = new ObjectMapper();
        objectMapper.setVisibility(PropertyAccessor.ALL, JsonAutoDetect.Visibility.ANY);
        objectMapper.disable(SerializationFeature.WRITE_DATES_AS_TIMESTAMPS);
        JavaTimeModule javaTimeModule = new JavaTimeModule();
        javaTimeModule.addSerializer(LocalDateTime.class,
                new LocalDateTimeSerializer(DateTimeFormatter.ofPattern("yyyy-MM-dd HH:mm:ss")));
        javaTimeModule.addSerializer(Long.class, ToStringSerializer.instance);
        javaTimeModule.addSerializer(Long.TYPE, ToStringSerializer.instance);
        objectMapper.registerModule(javaTimeModule);
        messageConverter.setObjectMapper(objectMapper);
        converters.add(0, messageConverter);
    }

}