Java中的json数据类型操作
package com.ss1.json; import java.util.ArrayList; import java.util.HashMap; import java.util.List; import java.util.Map; import org.json.JSONArray; import org.json.JSONException; import org.json.JSONObject; public class JsonParse { public static void main(String[] args) throws JSONException { //接收到的JSON字符串 String result = "[{\"username\" : \"yourname\",\"nickname\" : \"yournickname\"}]"; //根据字符串生成JSON对象 JSONArray json = new JSONArray(result); JSONObject resultJson = json.optJSONObject(0); //获取数据项 String username = resultJson.getString("username"); System.out.println(username); String jsonStr = "{\"id\": 2," + " \"title\": \"json title\", " + "\"config\": {" + "\"width\": 34," + "\"height\": 35," + "}, \"data\": [" + "\"JAVA\", \"JavaScript\", \"PHP\"" + "]}"; //创建JSONObject对象 JSONObject jsonObject = new JSONObject(jsonStr); System.out.println(jsonObject.getInt("id")); System.out.println(jsonObject.getString("title")); JSONObject config = jsonObject.getJSONObject("config"); System.out.println(config.getInt("width")); //向json中添加数据 JSONObject json1 = new JSONObject(); json1.put("username", "cmy"); json1.put("height", 172); json1.put("age", 23); //创建JSONArray数组,并将json添加到数组 JSONArray jsonArray1 = new JSONArray(); jsonArray1.put(json1); //转换为字符串 System.out.println(jsonArray1.toString()); //初始化ArrayList集合并添加数据 List<String> list = new ArrayList<String>(); list.add("username"); list.add("age"); list.add("sex"); //初始化HashMap集合并添加数组 Map map = new HashMap<>(); map.put("bookname","css/html"); map.put("price","42.0"); //初始化JSONArray对象,并添加数据 JSONArray array = new JSONArray(); array.put(list); array.put(map); System.out.println(array); } }