SpringMVC使用FastJson并解决长数值精度丢失问题

项目中很多时候都会用到json，常用的有fastjson，Jackson等等这些，有时候为了统一，我们通常就会约定使用某一种。
不管使用哪种，Spring MVC返回个前段Long类型的数据时，js在获取数据时会丢失精度，从而造成数据的不准确，解决方式呢，就是在序列化时，会将Long类型的数据转化为String类型
在使用Spring MVC默认的Jackson时，我们可以这么做：

1、编写FastJsonConfig扩展类

package com.chz.component.basic.configure;

import com.alibaba.fastjson.serializer.SerializeConfig;
import com.alibaba.fastjson.serializer.ToStringSerializer;
import com.alibaba.fastjson.support.config.FastJsonConfig;

import java.math.BigInteger;

public class FastJsonConfigExt extends FastJsonConfig {

public FastJsonConfigExt(){
super();
SerializeConfig serializeConfig = SerializeConfig.globalInstance;
serializeConfig.put(BigInteger.class, ToStringSerializer.instance);
serializeConfig.put(Long.class,ToStringSerializer.instance);
serializeConfig.put(Long.TYPE,ToStringSerializer.instance);
this.setSerializeConfig(serializeConfig);
}

}

2、配置SpringMvc.xml配置文件

<?xml version="1.0" encoding="UTF-8"?>
<beans xmlns="http://www.springframework.org/schema/beans"
xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
xmlns:mvc="http://www.springframework.org/schema/mvc"
xmlns:context="http://www.springframework.org/schema/context"
xmlns:aop="http://www.springframework.org/schema/aop"
xsi:schemaLocation="http://www.springframework.org/schema/beans http://www.springframework.org/schema/beans/spring-beans.xsd http://www.springframework.org/schema/context  http://www.springframework.org/schema/context/spring-context.xsd http://www.springframework.org/schema/mvc http://www.springframework.org/schema/mvc/spring-mvc.xsd http://www.springframework.org/schema/aop http://www.springframework.org/schema/aop/spring-aop.xsd"> 
<aop:aspectj-autoproxy proxy-target-class="true" />

<mvc:annotation-driven />

<bean id="conversionService" class="org.springframework.format.support.FormattingConversionServiceFactoryBean"/>

<bean id="webBindingInitializer" class="org.springframework.web.bind.support.ConfigurableWebBindingInitializer">
<property name="conversionService" ref="conversionService"/>
</bean>

<bean id="fastJsonConfigExt" class="com.chz.component.basic.configure.FastJsonConfigExt"/>

<bean class="org.springframework.web.servlet.mvc.method.annotation.RequestMappingHandlerAdapter">
<property name="webBindingInitializer" ref="webBindingInitializer"/>
<property name="messageConverters">
<list>
<bean class="org.springframework.http.converter.BufferedImageHttpMessageConverter"/>
<bean class="com.alibaba.fastjson.support.spring.FastJsonHttpMessageConverter">
<property name="fastJsonConfig" ref="fastJsonConfigExt" />
<property name="supportedMediaTypes">
<list>
<value>text/html;charset=UTF-8</value>
<value>application/json</value>
<value>application/xml;charset=UTF-8</value>
<value>application/x-www-form-urlencoded</value>
</list>
</property>

</bean>
</list>
</property>
</bean>

<context:annotation-config />

<context:component-scan base-package="com.chz.**.controller,com.cxkh.**.controller" />

<!-- 上传拦截，如最大上传值及最小上传值 -->
<bean id="multipartResolver"
class="org.springframework.web.multipart.commons.CommonsMultipartResolver">
<property name="defaultEncoding" value="utf-8" />
<property name="maxUploadSize" value="25474565" />
</bean>

<mvc:resources mapping="/static/**" location="classpath:static/"/>
<mvc:resources mapping="/*.html" location="/"/>
</beans>