JSON 字符串 与 java 对象的转换详解编程语言

 1. //把Map<String,Object> 对象列表转换为javaBean对象

　　BeanUtils.populate(exhibitions, map);

// 引入相应的包

//json-lib-2.2-jdk15.jar

import net.sf.json.JSONArray;
import net.sf.json.JSONObject;

1. //把java 对象列表转换为json对象数组，并转为字符串

    JSONArray array = JSONArray.fromObject(userlist);
    String jsonstr = array.toString();

2.//把java对象转换成json对象，并转化为字符串

  JSONObject object = JSONObject.fromObject(invite);
  Log4jInit.ysulogger.debug(object.toString());

3.//把JSON字符串转换为JAVA 对象数组

  String personstr = getRequest().getParameter(“persons”);
  JSONArray json = JSONArray.fromObject(personstr);
  List<InvoidPerson> persons = (List<InvoidPerson>)JSONArray.toCollection(json, nvoidPerson.class);
4.//把JSON字符串转换为JAVA 对象

str = “{/”lendperson/”:/”李四/”,/”lendcompany/”:/”有限公司/”,/”checkperson/”:/”李四/”,
  /”lenddate/”:/”2010-07-19T00:00:00/”,/”lendcounts/”:4,/”
  passports/”:[{/”passportid/”:/”d/”,/”name/”:/”李豫川/”,/”passporttype/”:/”K/”},
  {/”passportid/”:/”K9051/”,/”name/”:/”李平/”,/”passporttype/”:/”K/”},
  {/”passportid/”:/”K90517/”,/”name/”:/”袁寒梅/”,/”passporttype/”:/”K/”},
  {/”passportid/”:/”K905199/”,/”name/”:/”贺明/”,/”passporttype/”:/”K/”}]}”;
   JSONObject jsonobject = JSONObject.fromObject(str);
  PassportLendsEntity passportlends = null;
  try {
   //获取一个json数组
   JSONArray array = jsonobject.getJSONArray(“passports”);
   //将json数组 转换成 List<PassPortForLendsEntity>泛型
   List<PassPortForLendsEntity> list = new ArrayList<PassPortForLendsEntity>();
   for (int i = 0; i < array.size(); i++) {   
            JSONObject object = (JSONObject)array.get(i);  
            PassPortForLendsEntity passport = (PassPortForLendsEntity)JSONObject.toBean(object,
              PassPortForLendsEntity.class);
            if(passport != null){
             list.add(passport);
            }  
         }
   //转换PassportLendsEntity 实体类
   passportlends = (PassportLendsEntity)JSONObject.toBean(jsonobject, PassportLendsEntity.class);