Question

java解析json，The constructor JSONObject(String) is undefined，错哪了啊？？

///json-lib-2.4-jdk15.jar已导入
import net.sf.json.JSONArray;
import net.sf.json.JSONException;
import net.sf.json.JSONObject;

public class Test {

public static void main(String[] args) throws JSONException {
String jsonString = "{\"people\":[{\"firstName\":\"Brett\",\"lastName\":\"McLaughlin\",\"email\":\"aaaa\"},{\"firstName\":\"Jason\",\"lastName\":\"Hunter\",\"email\":\"bbbb\"},{\"firstName\":\"Elliotte\",\"lastName\":\"Harold\",\"email\":\"cccc\"}]}";
JSONObject dataJson = new JSONObject(jsonString);
JSONArray array = dataJson.getJSONArray("people");

for (int i = 0; i < array.length(); i++) {
System.out.println("array:" + array.get(i));
System.out.println("firstName:" + array.getJSONObject(i).get("firstName"));
System.out.println("lastName:" + array.getJSONObject(i).get("lastName"));
System.out.println("email:" + array.getJSONObject(i).get("email"));
}
}

}

Answer 1

import java.util.Iterator;

import net.sf.json.JSONArray;
import net.sf.json.JSONObject;

public class Test6
{
	public static void main(String[] args)
	{
		String str =
		        "{\"people\":[{\"firstName\":\"Brett\",\"lastName\":\"McLaughlin\",\"email\":\"aaaa\"},{\"firstName\":\"Jason\",\"lastName\":\"Hunter\",\"email\":\"bbbb\"},{\"firstName\":\"Elliotte\",\"lastName\":\"Harold\",\"email\":\"cccc\"}]}";
		JSONObject jo = JSONObject.fromString(str);
		JSONArray info = jo.getJSONArray("people");
		System.out.println(info);
		for(int i = 0; i < info.length(); i++)
		{
			JSONObject obj = info.getJSONObject(i);
			Iterator it = obj.keys();
			while(it.hasNext())
			{
				String key = (String) it.next();
				System.out.println(obj.get(key));
			}
		}
	}
}

Answer 2

net.sf.json.JSONObject这个类里面没有JSONObject(String)的初始化方法
所以不能那样初始化JSONObject实例