Map to JSON (java)

package com.blogspot.na5cent;

import java.util.Date;
import java.util.HashMap;
import java.util.Map;
import org.json.simple.JSONObject;

public class Test {
    public static void main(String[] args) {
        JSONObject json = new JSONObject();
        Map<String, Object> data = new HashMap<String, Object>();
        data.put("firstName", "redcrow");
        data.put("lastName", "na5cent");
        data.put("birthday", new Date(1989, 01, 01));
        data.put("address", "bangkok");
        data.put("age", 23);
        
        json.putAll(data);
        System.out.println(json.toJSONString());
    }
}

{
    "lastName":"na5cent",
    "birthday":Fri Feb 01 00:00:00 ICT 3889,
    "address":"bangkok",
    "age":23,
    "firstName":"redcrow"
}