Json lib JsonConfig用法

import java.util.Arrays;import java.util.List;import net.sf.json.JSONArray;import net.sf.json.JsonConfig;import net.sf.json.processors.JsonValueProcessor;public class JsonTest {      public static void main(String[] args) {JsonConfig jsonConfig = new JsonConfig();            jsonConfig.registerJsonValueProcessor(User.class, new JsonValueProcessor() {             public Object processArrayValue(Object value, JsonConfig jsonConfig) {                 User u=(User)value;                 return String.format("{\"id\":'%d',\"name\":\"%s\"}",u.getUserid(),u.getUsername());             }             public Object processObjectValue(String key, Object value, JsonConfig jsonConfig) {                 return value;             }         });         User user=new User();         user.setUserid(123);         user.setUsername("json-lib");                  List<User> users=Arrays.asList(user);        String data=JSONArray.fromObject(users,jsonConfig).toString();        System.out.println(data);     }}class User{private int userid;private String username;public int getUserid() {return userid;}public void setUserid(int userid) {this.userid = userid;}public String getUsername() {return username;}public void setUsername(String username) {this.username = username;}}