java - 将两个Map String组合成JSON

这是我期望的JSON字符串：

{
    "startDate": "2013-01-01",
    "columns": "mode , event",
    "endDate": "2013-02-01",
    "selection": {
        "selectionMatch": "123456789012",
        "selectionType": "smart"
    }
}

这是JAVA代码，但是我没有成功：

public static String BuildJson() throws JSONException{

    Map<String, String> map1 = new HashMap<String, String>();
    map1.put("startDate", "2013-01-01");
    map1.put("endDate", "2013-02-01");
    map1.put("columns", "mode , event");

    Map<String, String> map2 = new HashMap<String, String>();
    map2.put("selectionType", "smart");
    map2.put("selectionMatch", "123456789012");

    JSONArray ja2 = new JSONArray();
    ja2.put(map2);
    System.out.println(ja2.toString());

    map1.put("selection", ja2.toString());

    System.out.println();
    JSONArray ja = new JSONArray();
    ja.put(map1);
    System.out.println(ja.toString());

    return null;
}

面临的挑战是如何合并两个不在同一级别的映射字符串。
我的代码结果是：

[{"startDate":"2013-01-01","columns":"mode , event","endDate":"2013-02-01","selection":"[{\"selectionMatch\":\"123456789012\",\"selectionType\":\"smart\"}]"}]

有人可以帮我吗？

最佳答案

这是您想要的代码，

public static String BuildJson() throws JSONException
    {

        JSONObject map1 = new JSONObject();
        map1.put("startDate", "2013-01-01");
        map1.put("endDate", "2013-02-01");
        map1.put("columns", "mode , event");

        JSONObject map2 = new JSONObject();

        map2.put("selectionType", "smart");
        map2.put("selectionMatch", "123456789012");

        map1.put("selection",map2);

        System.out.println(map1.toString());

        return null;

    }

输出将是

{
   "startDate":"2013-01-01",
   "columns":"mode , event",
   "endDate":"2013-02-01",
   "selection":{
      "selectionMatch":"123456789012",
      "selectionType":"smart"
   }
}

使用JSONObject而不是Map，如果您需要JSONArray，则也可以使用它。