Long返回前段丢失精度

我会带着你远行 2021-09-29 01:42 313阅读 0赞

package com.tourism.sms.contact.message.init.configure;
    
    import com.fasterxml.jackson.databind.ObjectMapper;
    import com.fasterxml.jackson.databind.module.SimpleModule;
    import com.fasterxml.jackson.databind.ser.std.ToStringSerializer;
    import org.springframework.boot.web.servlet.MultipartConfigFactory;
    import org.springframework.context.annotation.Bean;
    import org.springframework.context.annotation.Configuration;
    import org.springframework.http.converter.HttpMessageConverter;
    import org.springframework.http.converter.json.MappingJackson2HttpMessageConverter;
    import org.springframework.stereotype.Component;
    import org.springframework.web.servlet.config.annotation.ResourceHandlerRegistry;
    import org.springframework.web.servlet.config.annotation.WebMvcConfigurationSupport;
    
    import javax.servlet.MultipartConfigElement;
    import java.util.List;
    
    /**
     * 解决前台返回Long类型精度损失的问题
     * @author 三多
     * @Time 2019/3/25
     */
    @Configuration
    public class WebConfig extends WebMvcConfigurationSupport {
        /**
         * 解决前端解析Long丢精度的问题
         * @param converters
         */
        @Override
        public void configureMessageConverters(List<HttpMessageConverter<?>> converters) {
            MappingJackson2HttpMessageConverter jackson2HttpMessageConverter = new MappingJackson2HttpMessageConverter();
            ObjectMapper objectMapper = new ObjectMapper();
            /**
             * 序列换成json时,将所有的long变成string
             * 因为js中得数字类型不能包含所有的java long值
             */
            SimpleModule simpleModule = new SimpleModule();
            simpleModule.addSerializer(Long.class, ToStringSerializer.instance);
            simpleModule.addSerializer(Long.TYPE, ToStringSerializer.instance);
            objectMapper.registerModule(simpleModule);
            jackson2HttpMessageConverter.setObjectMapper(objectMapper);
            converters.add(jackson2HttpMessageConverter);
        }
    
    
        /**
         * 解决 swagger-ui404问题
         * @param registry
         */
        @Override
        public void addResourceHandlers(ResourceHandlerRegistry registry) {
            registry.addResourceHandler("swagger-ui.html")
                    .addResourceLocations("classpath:/META-INF/resources/");
            registry.addResourceHandler("/webjars/**")
                    .addResourceLocations("classpath:/META-INF/resources/webjars/");
        }
    
    }

# [WebMvcConfigurerAdapter已过时，使用WebMvcConfigurationSupport或者WebMvcConfigurer来代替][WebMvcConfigurerAdapter_WebMvcConfigurationSupport_WebMvcConfigurer] #

如果上面全局修改失效采用下面注解模式，需要每个字段都添加

注解

import com.fasterxml.jackson.databind.annotation.JsonSerialize;
    
     ... 
    @JsonSerialize(using = ToStringSerializer.class) 
    private Long taskSn;

上面的方式只能解决返回前段是类对象的时候，或者是类列表的时候没问题，如果是多表联查会失效，可以采用sql修改类型

CAST(sm.BASE_ID AS CHAR) as baseId,

[WebMvcConfigurerAdapter_WebMvcConfigurationSupport_WebMvcConfigurer]: https://www.cnblogs.com/unknows/p/10620685.html