使用JSON -simple，您可以将数据JSON转换为映射和映射到JSON。

try
{
    JSONObject obj11 = new JSONObject();
    obj11.put(1, "Kishan");
    obj11.put(2, "Radhesh");
    obj11.put(3, "Sonal");
    obj11.put(4, "Madhu");

    Map map = new  HashMap();

    obj11.toJSONString();

    map = obj11;

    System.out.println(map.get(1));


    JSONObject obj12 = new JSONObject();

    obj12 = (JSONObject) map;

    System.out.println(obj12.get(1));
}
catch(Exception e)
{
    System.err.println("EROR : 01 :"+e);
}

如果你想要无库版本，这里是与regex的解决方案:

public static HashMap<String, String> jsonStringToMap(String inputJsonString) {
    final String regex = "(?:\\\"|\\')(?<key>[\\w\\d]+)(?:\\\"|\\')(?:\\:\\s*)(?:\\\"|\\')?(?<value>[\\w\\s-]*)(?:\\\"|\\')?";
    HashMap<String, String> map = new HashMap<>();
    final Pattern pattern = Pattern.compile(regex, Pattern.MULTILINE);
    final Matcher matcher = pattern.matcher(inputJsonString);

    while (matcher.find()) {
        for (int i = 1; i <= matcher.groupCount(); i++) {
            map.put(matcher.group("key"), matcher.group("value"));
        }
    }
    return map;
}

我只用了Gson

HashMap<String, Object> map = new Gson().fromJson(json.toString(), HashMap.class);

使用Gson，你可以做以下事情:

Map<String, Object> retMap = new Gson().fromJson(
    jsonString, new TypeToken<HashMap<String, Object>>() {}.getType()
);

使用JSON -simple，您可以将数据JSON转换为映射和映射到JSON。

try
{
    JSONObject obj11 = new JSONObject();
    obj11.put(1, "Kishan");
    obj11.put(2, "Radhesh");
    obj11.put(3, "Sonal");
    obj11.put(4, "Madhu");

    Map map = new  HashMap();

    obj11.toJSONString();

    map = obj11;

    System.out.println(map.get(1));


    JSONObject obj12 = new JSONObject();

    obj12 = (JSONObject) map;

    System.out.println(obj12.get(1));
}
catch(Exception e)
{
    System.err.println("EROR : 01 :"+e);
}

希望这能起作用，试试这个:

import com.fasterxml.jackson.databind.ObjectMapper;
Map<String, Object> response = new ObjectMapper().readValue(str, HashMap.class);

str，你的JSON字符串

就这么简单，如果你想要电子邮件，

String emailIds = response.get("email id").toString();