你好，这个报错如何解决?

代码如下:

package json;

import java.io.File;

public class JsonObjectSample {

public static void main(String[] args) {

// TODO Auto-generated method stub

}

private static void jSONObjectSample(){

JSONObject wangxiaoer = new JSONObject();

Object nullObj = null;

try{

   wangxiaoer.put("name","王小二");

   wangxiaoer.put("age",25.2);

       System.out.println(wangxiaoer.toString());

   }catch(JSONException e){

      e.printStackTrace();

   }

}

private static void createJsonByMap(){

Map<String,Object> wangxiaoer = new HashMap<String,Object>

wangxiaoer.put("name","王小二");

wangxiaoer.put("age",25.2);

System.out.println(new JSONObject(wangxiaoer).toString());

}

}

}