Simple JSON Implementation

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Simple JSON Implementation

The reason I made this (except for the fun of it) is that I found a couple of people had issues with incorporating "QJson":http://qjson.sourceforge.net/ in their projects (be it what it may). I reserve no copyrights to this implementation so you are all welcome to ctrl+c ctrl+v and do as you see fit with it.

JsonObject.hpp

#ifndef JSONOBJECT_HPP<br />#define JSONOBJECT_HPP

#include &lt;QVariant&amp;gt;

typedef QVariantList JsonArray;

class JsonObject<br />{<br />public:<br /> static const QString null;<br /> static const QString True;<br /> static const QString False;

JsonObject(QString jsonData = &quot;&quot;);

QString toString() const;

void put(const QString&amp;amp; id,JsonObject obj);<br /> void put(const QString&amp;amp; id,QString value);<br /> void put(const QString&amp;amp; id,int value);<br /> void put(const QString&amp;amp; id,double value);<br /> void put(const QString&amp;amp; id,qlonglong value);<br /> void put(const QString&amp;amp; id,JsonArray value);

JsonObject getObject(const QString&amp;amp; id, bool *ok = NULL) const;<br /> QString getString(const QString&amp;amp; id, bool *ok = NULL) const;<br /> int getInt(const QString&amp;amp; id, bool *ok = NULL) const;<br /> double getDouble(const QString&amp;amp; id, bool *ok = NULL) const;<br /> qlonglong getLong(const QString&amp;amp; id, bool *ok = NULL) const;<br /> JsonArray getArray(const QString&amp;amp; id, bool *ok = NULL) const;

bool isNull(const QString&amp;amp; id) const;

QVariantMap getRawData() const;<br />protected:<br /> void setRawData(QVariantMap data);

private:<br /> QString stringFromList(const JsonArray&amp;amp; array) const;<br /> QString getKey(QString&amp;amp; data);<br /> QString getValue(QString&amp;amp; data);<br /> JsonArray parseArray(QString data);

QVariantMap objectData;<br />};

#endif // JSONOBJECT_HPP<br />

Here's the cpp code:

JsonObject.cpp

#include "JsonObject.hpp"
#include <QStringList&gt;

QString JsonObject::toString() const
{
QString result = "{";
QStringList keys = objectData.keys();
for(int i = 0; i < keys.count(); +i)
{
QVariant data = objectData.value(keys.at(i));
switch(data.type())
{
case QVariant::Map:
{
result.append('"');
result.append(keys.at(i));
result.append('"');
result.append(':');
JsonObject obj;
obj.setRawData(data.toMap());
result.append(obj.toString());
result.append(',');
}
break;
case QVariant::String:
{
result.append('"');
result.append(keys.at(i));
result.append('"');
result.append(':');
if(data.toString() null || data.toString() True
|| data.toString() == False)
result.append(data.toString());
else
{
result.append('"');
result.append(data.toString());
result.append('"');
}
result.append(',');
}
break;
case QVariant::Int:
{
result.append('"');
result.append(keys.at(i));
result.append('"');
result.append(':');
result.append(QString("%1&quot;).arg(data.toInt()));
result.append(',');
}
break;
case QVariant::Double:
{
result.append('"');
result.append(keys.at(i));
result.append('"');
result.append(':');
result.append(QString("%1&quot;).arg(data.toDouble()));
result.append(',');
}
break;
case QVariant::LongLong:
{
result.append('"');
result.append(keys.at(i));
result.append('"');
result.append(':');
result.append(QString("%1&quot;).arg(data.toLongLong()));
result.append(',');
}
break;
case QVariant::List:
{
result.append('"');
result.append(keys.at(i));
result.append('"');
result.append(':');
result.append(stringFromList(data.toList()));
result.append(',');
}
break;
default:
break;
}
}
if(result.endsWith(','))
result.remove(result.length() - 1,1);
result.append("}");
return result;
}
void JsonObject::put(const QString&amp; id,JsonObject obj)
{
objectData.insert(id,QVariant(obj.getRawData()));
}
void JsonObject::put(const QString&amp; id,QString value)
{
if(value.startsWith('"'))
value.remove(0,1);
if(value.endsWith('"'))
value.remove(value.length() - 1,1);
objectData.insert(id,QVariant(value));
}
void JsonObject::put(const QString&amp; id,int value)
{
objectData.insert(id,QVariant(value));
}
void JsonObject::put(const QString&amp; id,double value)
{
objectData.insert(id,QVariant(value));
}
void JsonObject::put(const QString&amp; id,qlonglong value)
{
objectData.insert(id,QVariant(value));
}
void JsonObject::put(const QString&amp; id,JsonArray value)
{
objectData.insert(id,QVariant(value));
}
JsonObject JsonObject::getObject(const QString&amp; id, bool *ok) const
{
JsonObject result;
bool isOk = false;
if(objectData.contains(id))
{
QVariant data = objectData.value(id);
if(data.type() == QVariant::Map)
{
result.setRawData(data.toMap());
isOk = true;
}
}
if(ok != NULL)
*ok = isOk;
return result;
}
QString JsonObject::getString(const QString&amp; id, bool *ok) const
{
QString result = "";
bool isOk = false;
if(objectData.contains(id))
{
QVariant data = objectData.value(id);
if(data.type() == QVariant::String)
{
result = data.toString();
isOk = true;
}
}
if(ok != NULL)
*ok = isOk;
return result;
}
int JsonObject::getInt(const QString&amp; id, bool *ok) const
{
int result = 0;
bool isOk = false;
if(objectData.contains(id))
{
QVariant data = objectData.value(id);
if(data.type() == QVariant::Int)
{
result = data.toInt();
isOk = true;
}
}
if(ok != NULL)
*ok = isOk;
return result;
}
double JsonObject::getDouble(const QString&amp; id, bool *ok) const
{
double result = 0.0;
bool isOk = false;
if(objectData.contains(id))
{
QVariant data = objectData.value(id);
if(data.type() == QVariant::Double)
{
result = data.toDouble();
isOk = true;
}
}
if(ok != NULL)
*ok = isOk;
return result;
}
qlonglong JsonObject::getLong(const QString&amp; id, bool *ok) const
{
qlonglong result = 0;
bool isOk = false;
if(objectData.contains(id))
{
QVariant data = objectData.value(id);
if(data.type() == QVariant::LongLong)
{
result = data.toLongLong();
isOk = true;
}
}
if(ok != NULL)
*ok = isOk;
return result;
}
JsonArray JsonObject::getArray(const QString&amp; id, bool *ok) const
{
JsonArray result;
bool isOk = false;
if(objectData.contains(id))
{
QVariant data = objectData.value(id);
if(data.type() == QVariant::List)
{
result = data.toList();
isOk = true;
}
}
if(ok != NULL)
*ok = isOk;
return result;
}
bool JsonObject::isNull(const QString&amp; id) const
{
if(objectData.contains(id))
{
if(objectData.value(id).type() QVariant::String)

           return objectData.value(id).toString()  null;
 return false;
 }
 return true;
}

QVariantMap JsonObject::getRawData() const
{
return objectData;
}
void JsonObject::setRawData(QVariantMap data)
{
objectData = data;
}
QString JsonObject::stringFromList(const JsonArray& array) const
{
QString result = "[";
for(int i = 0; i < array.count();i)
{
QVariant data = array.at(i);
switch(data.type())
{
case QVariant::Map:
{
JsonObject obj;
obj.setRawData(data.toMap());
result.append(obj.toString());
result.append(',');
}
break;
case QVariant::String:
{
if(data.toString() null || data.toString() False || data.toString() == True)
result.append(data.toString());
else
{
result.append('"');
result.append(data.toString());
result.append('"');
}
result.append(',');
}
break;
case QVariant::Int:
{
result.append(QString("%1&quot;).arg(data.toInt()));
result.append(',');
}
break;
case QVariant::Double:
{
result.append(QString("%1&quot;).arg(data.toDouble()));
result.append(',');
}
break;
case QVariant::LongLong:
{
result.append(QString("%1&quot;).arg(data.toLongLong()));
result.append(',');
}
break;
case QVariant::List:
{
result.append(stringFromList(data.toList()));
result.append(',');
}
break;
default:
break;
}
}
if(result.endsWith(','))
result.remove(result.length() - 1,1);
result.append("]");
return result;
}
QString JsonObject::getKey(QString&amp; data)
{
QString key = "";
int index = data.indexOf(':');
if(index >= 0)
{
key = data.mid(0,index);
data.remove(0,index);
if(data.startsWith(':'))
data.remove(0,1);
}
if(key.startsWith('"'))
key.remove(0,1);
if(key.endsWith('"'))
key.remove(key.length() - 1,1);
return key;
}
QString JsonObject::getValue(QString&amp; data)
{
QString value = "";
if(data.startsWith('{'))//object
{
int index = data.indexOf('}');
if(index >= 0)
{
value.append(data.mid(0,index 1));
data.remove(0,index + 1);
while(value.count('{') > value.count('}'))
{
index = data.indexOf('}');
if(index >= 0)
{
value.append(data.mid(0,index + 1));
data.remove(0,index + 1);
}
else
{
value = "";
break;
}
}
if(data.startsWith(','))
data.remove(0,1);
}
}
else if(data.startsWith('['))//Array
{
int index = data.indexOf(']');
if(index >= 0)
{
value.append(data.mid(0,index + 1));
data.remove(0,index + 1);
while(value.count('[') > value.count(']'))
{
index = data.indexOf(']');
if(index >= 0)
{
value.append(data.mid(0,index + 1));
data.remove(0,index + 1);
}
else
{
value = "";
break;
}
}
if(data.startsWith(','))
data.remove(0,1);
}
}
else
{
int index = data.indexOf(',');
if(index >= 0)
{
value = data.mid(0,index);
data.remove(0,index);
if(data.startsWith(','))
data.remove(0,1);
}
else if(!data.contains(','))
{
value = data;
data.clear();
}
}
return value;
}

JsonArray JsonObject::parseArray(QString data)
{
JsonArray result;
if(data.startsWith('[') && data.endsWith(']'))
{
data.remove(0,1);
data.remove(data.length() - 1,1);
while(data.length() > 0)
{
QString value = getValue(data);
if(value.startsWith('{'))//Object
{
JsonObject obj(value);
result.append(QVariant(obj.getRawData()));
}
else if(value.startsWith('['))//Array
{
JsonArray array = parseArray(value);
result.append(QVariant(array));
}
else if(value.startsWith('"'))//String
{
value.remove(0,1);
if(value.endsWith('"'))
value.remove(value.length() - 1,1);
result.append(QVariant(value));
}
else if(value null)

               result.append(QVariant(null));
           else if(value  True)
 result.append(QVariant(True));
 else if(value == False)
 result.append(QVariant(False));
 else//Number
 {
 if(value.contains('.'))//double
 {
 bool ok;
 double doubleValue = value.toDouble(&ok);
 if(ok)
 result.append(QVariant(doubleValue));
 else
 result.append(QVariant(0.0));
 }
 else//int || long
 {
 bool ok;
 int intValue = value.toInt(&ok);
 if(ok)
 result.append(QVariant(intValue));
 else
 {
 qlonglong longValue = value.toLongLong(&ok);
 if(ok)
 result.append(QVariant(longValue));
 else
 result.append(QVariant(0));
 }
 }
 }
 }
 }
 return result;
}

JsonObject::JsonObject(QString jsonData)
{
if(jsonData.startsWith('{') && jsonData.endsWith('}'))
{
jsonData.remove(0,1);
jsonData.remove(jsonData.length() - 1,1);
while(jsonData.length() > 0)
{
QString key = getKey(jsonData);
QString value = getValue(jsonData);
if(value.startsWith('{'))//Object
this->put(key,JsonObject(value));
else if(value.startsWith('['))//Array
{
JsonArray array = parseArray(value);
this->put(key,array);
}
else if(value.startsWith('"'))//String
this->put(key,value);
else if(value null)

               this->put(key,null);
           else if(value  True)
 this->put(key,True);
 else if(value == False)
 this->put(key,False);
 else//Number
 {
 if(value.contains('.'))//double
 {
 bool ok;
 double doubleValue = value.toDouble(&ok);
 if(ok)
 this->put(key,doubleValue);
 else
 this->put(key,0.0);
 }
 else//int || long
 {
 bool ok;
 int intValue = value.toInt(&ok);
 if(ok)
 this->put(key,intValue);
 else
 {
 qlonglong longValue = value.toLongLong(&ok);
 if(ok)
 this->put(key,longValue);
 else
 this->put(key,0);
 }
 }
 }
 }
 }
}

const QString JsonObject::null = "null&quot;;
const QString JsonObject::True = "true&quot;;
const QString JsonObject::False = "false&quot;;