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String转成JSON的实现

String转成JSON的实现

作者: e4e9aa34f536 | 来源:发表于2018-11-21 19:43 被阅读3次

String转成JSON

这个依赖很重要,我们将围绕fastjson中的JSONObject这个类来谈转换

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<dependency>

<groupId>com.alibaba</groupId>

<artifactId>fastjson</artifactId>

<version>1.2.15</version>

</dependency>

String转成JSON

String json = "{"abc":"1","hahah":"2"}";

JSONObject jsonObject = JSONObject.parseObject(content);

一句话就能解决,非常便捷。

想要取出值,可以对`jsonObject`进行操作:

jsonObject.getString("abc");

结果为:`1`

将String转为list后转为JSON

List<String> list = new ArrayList<String>();

list.add("username");

list.add("age");

list.add("sex");

JSONArray array = new JSONArray();

array.add(list);

将String转为map后转为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);

特别注意:从JSONObject中取值,碰到了数字为key的时候,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"

}

获取“userAnswer”的value,再转成JSON,可仿照如下形式:

JSONObject userJson = JSONObject.parseObject(jsonObject.getString("userAnswer"));

但是想获取key"28568"就没这么容易了。直接像上述的写法,会报错。

我们浏览fastjson中的源码,总结下,应该如下写:

JSONObject question = (JSONObject) JSONObject.parseObject(section.getString("28568"), Object.class);

整体代码:

dao代码很容易,就不贴出来了。

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 {

//查询数据Dao

@Autowired

private ELearningChoiceRecordDao eLearningChoiceRecordDao;

//转储数据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");

/**

* 定时任务,每天定时将E学网考试数据分析并转储

*

* @param : instanceIdList

* @return : void

* @author : 28370·皮育才

* @date : 2018/11/20

**/

@Scheduled(cron = "00 00 01 * * ?")

public void analysisChoiceRecord() {

//获取前一天的时间

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);

//针对本section的"公共"属性直接设置

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"));

//针对section中的题目进行细化循环拆分

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()) {

//对每个question进行再次拆分出题目

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);

}

}

}

}

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