??????參考：技術(shù)參考-大幸運(yùn)的博客技術(shù)站

1，

String output = FileUtils.ReadFile(url);
    System.out.println(output);
    JSONArray jsonArray =  JSONObject.parseArray(output);
    return jsonArray;

2，String轉(zhuǎn)成JSON的實(shí)現(xiàn)_javaQQ561487941的博客-CSDN博客_string轉(zhuǎn)成json

String轉(zhuǎn)成JSON
String json = “{“abc”:”1″,”hahah”:”2″}”;
JSONObject jsonObject = JSONObject.parseObject(content);
一句話就能解決，非常便捷。

想要取出值，可以對(duì)`jsonObject`進(jìn)行操作：
jsonObject.getString(“abc”);
結(jié)果為：`1`
將String轉(zhuǎn)為list后轉(zhuǎn)為JSON
List<String> list = new ArrayList<String>();
list.add(“username”);
list.add(“age”);
list.add(“sex”);
JSONArray array = new JSONArray();
array.add(list);
將String轉(zhuǎn)為map后轉(zhuǎn)為JSON
Map<String, String> map = new HashMap<String, String>();
map.put(“abc”, “abc”);
map.put(“def”, “efg”);
JSONArray array_test = new JSONArray();
array_test.add(map);
JSONObject jsonObject = JSONObject.fromObject(map);
特別注意:從JSONObject中取值，碰到了數(shù)字為key的時(shí)候，如

{

“userAnswer”: {

“28568”: {

“28552”: {

“qId”: “28552”,
“order”: “1”,
“userScore”: {

“score”: 100
},
“answer”: {

“28554”: “28554”
},
“qScore”: “100.0”,
“qtype”: “SingleChoice”,
“sId”: “28568”
}
}
},
“paperType”: “1”,
“paperOid”: “28567”,
“instanceId”: 30823,
“remainingTime”: -1,
“examOid”: “28570”
}
獲取“userAnswer”的value,再轉(zhuǎn)成JSON,可仿照如下形式：
JSONObject userJson = JSONObject.parseObject(jsonObject.getString(“userAnswer”));
但是想獲取key”28568″就沒(méi)這么容易了。直接像上述的寫法，會(huì)報(bào)錯(cuò)。
我們?yōu)g覽fastjson中的源碼，總結(jié)下，應(yīng)該如下寫：
JSONObject question = (JSONObject) JSONObject.parseObject(section.getString(“28568”), Object.class);
整體代碼：

dao代碼很容易，就不貼出來(lái)了。
package com.xiamenair.training.business.service;
import com.alibaba.fastjson.JSONObject;
import com.xiamenair.training.business.dao.elearningdao.ELearningExamInstanceDao;
import com.xiamenair.training.business.dao.masterdao.ELearningChoiceRecordDao;
import com.xiamenair.training.business.model.LasChoiceRecord;
import com.xiamenair.training.business.model.entity.elearning.LasExamInstance;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.scheduling.annotation.Scheduled;
import org.springframework.stereotype.Service;
import java.math.BigDecimal;
import java.sql.Blob;
import java.sql.SQLException;
import java.text.SimpleDateFormat;
import java.util.*;
@Service
public class ChoiceRecordService {

//查詢數(shù)據(jù)Dao
@Autowired
private ELearningChoiceRecordDao eLearningChoiceRecordDao;
//轉(zhuǎn)儲(chǔ)數(shù)據(jù)Dao
@Autowired
private ELearningExamInstanceDao eLearningExamInstanceDao;
private ChoiceRecordService() {

}
private static class SingletonRecordInstance {

private static final LasChoiceRecord choiceRecord = new LasChoiceRecord();
}
public static LasChoiceRecord getMapInstance() {

return SingletonRecordInstance.choiceRecord;
}
private static SimpleDateFormat simpleDateFormat = new SimpleDateFormat(“yyyy-MM-dd”);
/**
* 定時(shí)任務(wù)，每天定時(shí)將E學(xué)網(wǎng)考試數(shù)據(jù)分析并轉(zhuǎn)儲(chǔ)
*
* @param : instanceIdList
* @return : void
* @author : 28370·皮育才
* @date : 2018/11/20
**/
@Scheduled(cron = “00 00 01 * * ?”)
public void analysisChoiceRecord() {

//獲取前一天的時(shí)間
Date date = new Date();
Calendar calendar = Calendar.getInstance();
calendar.setTime(date);
calendar.add(calendar.DATE, -1);
date = calendar.getTime();
String dateString = simpleDateFormat.format(date);
List<BigDecimal> instanceIdList = eLearningExamInstanceDao.findInstanceIdByFinishTime(dateString);
if(0 != instanceIdList.size()){

LasChoiceRecord lasChoiceRecord = getMapInstance();
instanceIdList.stream().forEach(instanceId -> {

Blob answerBlob = eLearningExamInstanceDao.findUserAnswer(instanceId);
Long userId = eLearningExamInstanceDao.findUserId(instanceId);
String content = null;
try {

content = new String(answerBlob.getBytes((long) 1, (int) answerBlob.length()));
} catch (SQLException e) {

e.printStackTrace();
System.out.println(“SQLEXCEPTION:” + e);
}
JSONObject jsonObject = JSONObject.parseObject(content);
//針對(duì)本section的”公共”屬性直接設(shè)置
lasChoiceRecord.setUserId(userId);
lasChoiceRecord.setPaperType(jsonObject.getString(“paperType”));
lasChoiceRecord.setPaperId(jsonObject.getString(“paperOid”));
lasChoiceRecord.setExamInstanceId(jsonObject.getString(“instanceId”));
lasChoiceRecord.setRemainingTime(jsonObject.getString(“remainingTime”));
lasChoiceRecord.setExamId(jsonObject.getString(“examOid”));
//針對(duì)section中的題目進(jìn)行細(xì)化循環(huán)拆分
JSONObject userJson = JSONObject.parseObject(jsonObject.getString(“userAnswer”));
Set sectionSet = userJson.keySet();
Iterator<String> setIt = sectionSet.iterator();
analyzeAnswer(lasChoiceRecord, userJson, setIt);
});
}
}
private void analyzeAnswer(LasChoiceRecord lasChoiceRecord, JSONObject userJson, Iterator<String> setIt) {

while (setIt.hasNext()) {

//對(duì)每個(gè)question進(jìn)行再次拆分出題目
JSONObject section = (JSONObject) JSONObject.parseObject(userJson.getString(setIt.next()), Object.class);
Set questionSet = section.keySet();
Iterator<String> queIt = questionSet.iterator();
while (queIt.hasNext()) {

JSONObject question = (JSONObject) JSONObject.parseObject(section.getString(queIt.next()), Object.class);
String userAnswer = question.getString(“answer”);
String userScore = question.getString(“userScore”);
lasChoiceRecord.setQuestionId(question.getString(“qId”));
lasChoiceRecord.setRecordId(UUID.randomUUID().toString());
eLearningChoiceRecordDao.save(lasChoiceRecord);
}
}
}
}
———————
作者：JavaQQ群854630135
來(lái)源：CSDN
原文：https://blog.csdn.net/javaQQ561487941/article/details/84328669
版權(quán)聲明：本文為博主原創(chuàng)文章，轉(zhuǎn)載請(qǐng)附上博文鏈接！

不知道為啥

String json = “{“abc”:”1″,”hahah”:”2″}”;
JSONObject jsonObject = JSONObject.parseObject(content);

會(huì)一直抱錯(cuò)， object這個(gè)好像不行

7-1

今天遇到的這個(gè)問(wèn)題，找了很多辦法

最后這樣解決的

src ：

[{“comcode”:”2143214″,”licenseno”:”粵·13″,”qqq”:”2131233123″,”startdate”:”2019-01-01″},

{“comcode”:”124124″,”licenseno”:”粵·1338″,”qqqq”:”1231233123123″,”startdate”:”2019-01-01″}]

JSONArray ja = JSONArray.parseArray(src); //把字符串轉(zhuǎn)成json數(shù)組

String one = ja.getString(0); //取第一個(gè)元素

JSONObject jb123 = JSONObject.parseObject(one); //把這一個(gè)json串轉(zhuǎn)成 json對(duì)象

System.out.println(“licenseno is —————+ jb123.get(“licenseno”)); //獲取屬性值

一開(kāi)始寫的是 把src直接傳進(jìn)到 parseObject 直接報(bào)錯(cuò)

com.alibaba.fastjson.JSONArray cannot be cast to com.alibaba.fastjson.JSONObject

debug進(jìn)去JSONObject 方法，慢慢發(fā)現(xiàn)，只能傳一個(gè){sadasdasd}這樣的json格式的字段，不能傳多個(gè)，[] 也不能有，嘗試把src 的【】用replace 去掉，也不能去掉中間那個(gè)逗號(hào)

所以最后思路

把字符串轉(zhuǎn)成 json格式的數(shù)據(jù)，然后再取了再傳進(jìn)去變成jsonobject

這樣就能獲取到一個(gè)json對(duì)象的對(duì)應(yīng)屬性 元素

所以啊 要多用 debug 多看底層源碼 搞懂為啥

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