Question

怎么把string转成json

Answer 1

你需要用到第三方的lib文件： json-lib。
From Beans to JSON：
class MyBean{
private String name = "json";
private int pojoId = 1;
private char[] options = new char[];
private String func1 = "function(i)";
private JSONFunction func2 = new JSONFunction(new String[],"return this.options[i];");
// getters & setters
...
}
JSONObject jsonObject = JSONObject.fromObject( new MyBean() );
System.out.println( jsonObject );
/* prints
{"name":"json","pojoId":1,"options":["a","f"],
"func1":function(i),
"func2":function(i)}
*/
在你这里就是：JSONObject jsonObject = JSONObject.fromObject(user );
From JSON to Beans：
String json = "";
JSONObject jsonObject = JSONObject.fromObject( json );
BeanA bean = (BeanA) JSONObject.toBean( jsonObject, BeanA.class );
在你这里就是：
JSONObject jsonObject = JSONObject.fromObject( json );
User bean = (User) JSONObject.toBean( jsonObject, User.class );