JSON 字符串 与 java 对象的转换

jsonLib
经典文章：http://json-lib.sourceforge.net/xref-test/net/sf/json/TestJSONObject.html

// 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);