在新的Jsoncpp中 Json::Writer、Json::FastWriter、Json::Reader 等都被摒弃了，
用了新的Json::StreamWriterBuilder、Json::CharReaderBuilder代替。
示例代码如下：

#include <iostream>
#include <string>
#include <fstream>
#include <sstream>
#include "json/json.h"

std::string createJson()
{
    std::string jsonStr;
    Json::Value root, lang, mail;
    Json::StreamWriterBuilder writerBuilder;
    std::ostringstream os;

    root["Name"] = "monk";
    root["Age"] = 30;

    lang[0] = "C++";
    lang[1] = "Java";
    lang[2] = "Python";
    root["Language"] = lang;

    mail["Netease"] = "[email protected]";
    mail["Hotmail"] = "[email protected]";
    root["E-mail"] = mail;

    std::unique_ptr<Json::StreamWriter> jsonWriter(writerBuilder.newStreamWriter());
    jsonWriter->write(root, &os);
    jsonStr = os.str();

    std::cout << "Json:\n" << jsonStr << std::endl;
    return jsonStr;
}

bool parseJson(const std::string& info)
{
    if(info.empty()){
        return false;
    }

    bool res;
    JSONCPP_STRING errs;
    Json::Value root, lang, mail;
    Json::CharReaderBuilder readerBuilder;

    std::unique_ptr<Json::CharReader> const jsonReader(readerBuilder.newCharReader());
    res = jsonReader->parse(info.c_str(), info.c_str() + info.length(), &root, &errs);
    if(!res || !errs.empty()){
        std::cout << "parseJson err. " << errs << std::endl;
    }

    std::cout << "Name: " << root["Name"].asString() << std::endl;
    std::cout << "Age: " << root["Age"].asInt() << std::endl;

    lang = root["Language"];
    std::cout << "Language: ";
    for (int i = 0; i < lang.size(); ++i) {
        std::cout << lang[i] << " ";
    }
    std::cout << std::endl;

    mail = root["E-mail"];
    std::cout << "Netease: " << mail["Netease"].asString() << std::endl;
    std::cout << "Hotmail: " << mail["Hotmail"].asString() << std::endl;

    return true;
}

void json_test1()
{
    std::string json_str = createJson();
    parseJson(json_str);
}

int main(int argc, char **argv)
{
    json_test1();
    return 0;
}