json和java转换

public static void main(String[] args) throws JsonParseException, JsonMappingException, IOException {

JSONObject json = new JSONObject();

json.put("id","1");

json.put("name","张三");

json.put("address","陕西西安市");

json.put("sex","男神");

json.put("age","1");

//fromObject将Java对象转换成json字符串，

//toBean将json对象转换成Java对象；

//将json转为为bean

System.out.println("=======将json转为为bean===========");

People people = (People) JSONObject.toBean(json, People.class);

System.out.println(people.getAddress());

//获取json，然后依次添加bean中

System.out.println("=======获取json，然后依次添加bean中===========");

JSONArray jsonArray = JSONArray.fromObject(json);

for(int i=0;i<jsonArray.size(); i++){

JSONObject jsonJ=jsonArray.getJSONObject(i);

jsonJ.getInt("id");

jsonJ.getString("name");

jsonJ.getString("address");

System.out.println(jsonJ.getString("address"));

}

//然后把bean转换为json传给前台

System.out.println("=======然后把bean转换为json传给前台===========");

People p1=new People();

p1.setId("1");

p1.setName("张岱年");

p1.setAddress("1");

p1.setSex("男");

p1.setAge(0);

JSONObject.fromObject(p1).toString();

//JSONArray.fromObject(p1).toString();

System.out.println(JSONObject.fromObject(p1).toString());

System.out.println(JSONArray.fromObject(p1).toString());

System.out.println(JSONSerializer.toJSON(p1).toString());

//转换 List集合到JSON

//如果你是转换List集合，一定得用JSONArray或是JSONSrializer提供的序列化方法。

//如果你用JSONObject.fromObject方法转换List会出现异常，

//通常使用JSONSrializer这个JSON序列化的方法，它会自动识别你传递的对象的类型，然后转换成相应的JSON字符串。

System.out.println("转换 List集合到JSON");

List<People> stu = new ArrayList<People>();

stu.add(p1);

JSONArray.fromObject(p1).toString();

//System.out.println(JSONObject.fromObject(p1).toString());

System.out.println(JSONArray.fromObject(p1).toString());

//将Map集合转换成JSON对象

System.out.println("将Map集合转换成JSON对象");

Map<String, Object> map = new HashMap<String, Object>();

 map.put("p", p1);

 map.put("int", new Integer(1));

 map.put("arr", new String[] { "a", "b" });

 map.put("func", "function(i){return this.arr[i]; }");

 JSONObject.fromObject(map).toString();

 JSONArray.fromObject(map).toString();

 JSONSerializer.toJSON(map).toString();

 System.out.println(JSONObject.fromObject(map).toString());

 System.out.println(JSONArray.fromObject(map).toString());

 System.out.println(JSONSerializer.toJSON(map).toString());

 //将更多类型转换成JSON

 System.out.println("将更多类型转换成JSON");

 String[] sa = {"a", "b", "c"};

 JSONArray.fromObject(sa).toString();

 JSONSerializer.toJSON(sa).toString();

 System.out.println(JSONArray.fromObject(sa).toString());

 System.out.println(JSONSerializer.toJSON(sa).toString());

}