java对象与JSON对象的互换

jar 包

json - 20090211.jar (Myeclipse 自带jar包)

1.java 对象列表转换成json对象数组

List list = new ArrayList();

JSONArray jsonArray = JSONArray.fromObject(list);

String jsonstr = jsonArray.toString ();

2.java对象转换成json对象

JSONＯbject jsonObject = JSONObject.fromObject(object);

3.json字符串转换为Java对象

String personstr =getRequest().getParameter(“persons”);

JSONArray json =JSONArray.fromObject(personstr);

Listpersons =(List)JSONArray.toCollection(json,nvoidPerson.class);

4 json 字符串转换成java对象

JSONObject jsonObject = new JSONObject (objectStr) ;

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\”}]}”;

JSONObjectjsonobject = JSONObject.fromObject(str);

PassportLendsEntitypassportlends = null;

try {

//获取一个json数组

JSONArrayarray = jsonobject.getJSONArray(“passports”);

//将json数组 转换成List泛型

Listlist = newArrayList();

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);