Java讀取Json數據

一、Json示例

{
    "resCode":0,
    "msg":"SUCCESS",
    "firstJson":{
        "secondJson":"sencondJson value",
        "secondJson1":[
            {
                "thirdJson":1234,
                "thirdJson1":[
                    {
                        "fourthJson":[
                            {
                                "fifthJson":true
                            }
                        ]
                    }
                ],
                "thirdJson2":{
                    "fourthJsonList":"fourthJson list value",
                    "fourthJsonList1":"fourthJson list value1"
                }
            }
        ],
        "secondJson2":{
            "thirdJsonList":"thirdJson list value",
            "thirdJsonList1":"thirdJson list value1"
        }
    }
}

二、Java代碼

import com.alibaba.fastjson.JSONArray;
import com.alibaba.fastjson.JSONObject;

public class JsonUtil {
    /**
     * 獲取json串某一字段的值
     *
     * @param response 接口返回的json值轉換後
     * @param keys     調用示例 String str = JsonUtils.getJsonValueRec(string,"data.departments.subDepartments.name",0);
     * @param index    需要取列表中第幾個的值，一般傳0就可以
     * @return 返回String類型的結果值
     */
    public static String getJsonValueRec(String response, String keys, int index) {
        String[] key = keys.split("\\.");
        if (key.length == 1) {
            if (response.startsWith("[")) {
                return parseJsonArray(response, index, key[0]);
            }
            if (response.startsWith("{")) {
                return parseJsonObject(response, key[0]);
            }
        } else if (key.length > 1) {
            if (response.startsWith("[")) {
                response = parseJsonArray(response, index, key[0]);
                keys = keys.substring(key[0].length() + 1);
                return getJsonValueRec(response, keys, index);
            }
            if (response.startsWith("{")) {
                response = parseJsonObject(response, key[0]);
                keys = keys.substring(key[0].length() + 1);
                return getJsonValueRec(response, keys, index);
            }
        }
        return "No corresponding value found";
    }

    private static String parseJsonArray(String response, int index, String key) {
        JSONArray resultArray = JSONObject.parseArray(response);
        return resultArray.getJSONObject(index).getString(key);
    }

    private static String parseJsonObject(String response, String key) {
        JSONObject jsonObject = JSONObject.parseObject(response);
        return jsonObject.get(key).toString();
    }
}