JAVA对象JSON数据互相转换的四种常见情况

时间：2022-05-14 10:00:46|栏目：JAVA代码|点击：次

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

复制代码代码如下:

 
   JSONObject object = JSONObject.fromObject(invite);
 
    String str=object.toString());

3.把JSON字符串转换为JAVA 对象数组

复制代码代码如下:

 
   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

复制代码代码如下:

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);

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\"}]}";

相关的jar包：