json字符串怎么取值啊!,求大神帮帮忙

String jsonStr = {"entry":[{"key":"a","value":"123"},{"key":"b","value":"456"}]}
怎么根据key取到值呢

    public static void main(String[] args) {
        String key = "a";
        String value = "";
        String jsonStr = "{\"entry\":[{\"key\":\"a\",\"value\":\"123\"},{\"key\":\"b\",\"value\":\"456\"}]}";
        String entry = JSON.parseObject(jsonStr).get("entry").toString();
        List<JSONObject> jsonObjects = JSON.parseArray(entry, JSONObject.class);
        for (JSONObject jsonObject : jsonObjects) {
            if (key.equals(jsonObject.get("key"))) {
                value = jsonObject.get("value").toString();
                break;
            }
            throw new RuntimeException("未找到");
        }
        System.out.println(value);

    }

Map json = (Map) JSONObject.parse(jsonStr ); 用FastJson即可

String jsonStr = "{\"entry\":[{\"key\":\"a\",\"value\":\"123\"},{\"key\":\"b\",\"value\":\"456\"}]}";
        Map<String,Object> paramMap = (Map<String,Object>)JSONObject.parse(jsonStr) ;
        String entry = paramMap.get("entry").toString();
        List<Map<String,Object>> entryObjectList = (List<Map<String,Object>>)JSONObject.parse(entry) ;
        System.out.println(entryObjectList);
        entryObjectList.forEach(map->{
            if("a".equals(map.get("key"))){
                System.out.println(map.get("value"));
            }
        });