json.tojsonstring格式化成json字符串时保留null属性
使用阿里的
com.alibaba.fastjson.json
格式化时，默认null属性会被过滤掉，可以设置不过滤null
public static string parsescriptjsonstringwithnullvalue(object obj) {
if (obj == null || (obj instanceof undefined)) {
return null;
}
return json.tojsonstring(obj, new serializefilter[]{scriptarrayfilter}, serializerfeature.writemapnullvalue);
}
指定这个参数即可
serializerfeature.writemapnullvalue
属性说明
quotefieldnames———输出key时是否使用双引号,默认为true
writemapnullvalue———是否输出值为null的字段,默认为false
writenullnumberaszero———数值字段如果为null,输出为0,而非null
writenulllistasempty———list字段如果为null,输出为[],而非null
writenullstringasempty———字符类型字段如果为null,输出为”“,而非null
writenullbooleanasfalse———boolean字段如果为null,输出为false,而非null
例子
string ret = json.tojsonstringwithdateformat(returnvalue, "yyyy-mm-dd hh:mm:ss", serializerfeature.prettyformat, // 保留map空的字段 serializerfeature.writemapnullvalue, // 将string类型的null转成"" serializerfeature.writenullstringasempty, // 将number类型的null转成0 serializerfeature.writenullnumberaszero, // 将list类型的null转成[] serializerfeature.writenulllistasempty, // 将boolean类型的null转成false serializerfeature.writenullbooleanasfalse, // 避免循环引用 serializerfeature.disablecircularreferencedetect );
处理返回结果中字段为空或为null,不展示字段的问题(字段展示不全)
package com.aiqin.mgs.market.api.config;
import com.alibaba.fastjson.serializer.serializerfeature;
import com.alibaba.fastjson.support.config.fastjsonconfig;
import com.alibaba.fastjson.support.spring.fastjsonhttpmessageconverter;
import org.springframework.context.annotation.configuration;
import org.springframework.http.mediatype;
import org.springframework.http.converter.httpmessageconverter;
import org.springframework.web.servlet.config.annotation.resourcehandlerregistry;
import org.springframework.web.servlet.config.annotation.webmvcconfigurationsupport;
import java.nio.charset.charset;
import java.util.arraylist;
import java.util.list;
/**
* description: fastjson处理返回的参数为null、或者不返回
* date: 2019/11/22 15:03
* author: hantao
* version: 1.0
* springboot 处理返回结果中字段为空或为null，不展示字段的问题（字段展示不全）
*/
@configuration
public class fastjsonconfiguration extends webmvcconfigurationsupport {
/**
* 使用阿里 fastjson 作为json messageconverter
* @param converters
*/
@override
public void configuremessageconverters(list<httpmessageconverter<?>> converters) {
fastjsonhttpmessageconverter converter = new fastjsonhttpmessageconverter();
fastjsonconfig config = new fastjsonconfig();
config.setserializerfeatures(
// 保留map空的字段
serializerfeature.writemapnullvalue,
// 将string类型的null转成""
serializerfeature.writenullstringasempty,
// 将number类型的null转成0
serializerfeature.writenullnumberaszero,
// 将list类型的null转成[]
serializerfeature.writenulllistasempty,
// 将boolean类型的null转成false
serializerfeature.writenullbooleanasfalse,
// 避免循环引用
serializerfeature.disablecircularreferencedetect);
converter.setfastjsonconfig(config);
converter.setdefaultcharset(charset.forname("utf-8"));
list<mediatype> mediatypelist = new arraylist<>();
// 解决中文乱码问题，相当于在controller上的@requestmapping中加了个属性produces = "application/json"
mediatypelist.add(mediatype.application_json);
converter.setsupportedmediatypes(mediatypelist);
converters.add(converter);
}
/**
* 整合了swagger需要配置swagger拦截
* @param registry
*/
@override
public void addresourcehandlers(resourcehandlerregistry registry) {
registry.addresourcehandler("swagger-ui.html","index.html").addresourcelocations("classpath:/meta-inf/resources/");
registry.addresourcehandler("doc.html").addresourcelocations("classpath:/meta-inf/resources/");
registry.addresourcehandler("/webjars/**").addresourcelocations("classpath:/meta-inf/resources/webjars/");
registry.addresourcehandler("/static/**").addresourcelocations("classpath:/meta-inf/resources/static/");
}
}
以上为个人经验，希望能给大家一个参考，也希望大家多多支持。
