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Poco::JSON::Array 中object 设置preserveInsertionOrder 时,stringify出错-->深入解析

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在使用poco version 1.6.0时 Poco::JSON::Array 在object  设置preserveInsertionOrder =true 时

调用 array.stringify出错.

在使用poco::json 输出字符串

std::string str1 = "\r";
std::string str2 = "\n";
Poco::JSON::Object obj1, obj2;
obj1.set("payload", str1);
obj2.set("payload", str2);
std::ostringstream oss1, oss2;
Poco::JSON::Stringifier::stringify(obj1, oss1);
Poco::JSON::Stringifier::stringify(obj2, oss2); string srxxx=oss1.str()//正常输出...

poco::json::array 输出 字符串:

Object jObj2(true); std::string strValue2="[{\"backspace1\":\"bs2222\",\"1backspace1\":\"1bs2222\"},{\"te1\":\"t1\",\"t2\":\"t2\"}]";
jObj2.set("car", "这是中文abc@qwe.com1231");
jObj2.set("baz", "fas"); std::stringstream ss2222;
jObj2.stringify(ss2222);
strxxx.clear();
strxxx=CMyCodeConvert::Gb2312ToUtf8(ss2222.str());//gbk->utf8 Object jObj3(true); jObj3.set("", "");
jObj3.set("", ""); Object jObj4(false); jObj4.set("", "");
jObj4.set("", ""); Poco::JSON::Array array1; //array1.add(resultxxx);
array1.add(jObj2);
array1.add(jObj3);
array1.add(jObj4);
//jObj.set("arrar",array1); std::stringstream ssArray1;
Stringifier::stringify(array1,ssArray1);
//array1.stringify(ssArray1);
std::string strArray1=ssArray1.str();//->>>>>>输出字符串出错.

but run time is error

追踪代码发现:

\JSON\src\Object.cpp:

Object(bool preserveInsertionOrder = false); //在map 中排序 ,输出时按字母大小顺序.
/// Default constructor. If preserveInsertionOrder, object
/// will preserve the items insertion order. Otherwise, items
/// will be sorted by keys.

preserveInsertionOrder = false 这个我比较反感,因为之前用jsoncpp 处理 某些东东时,因为输出时入 输入的json顺序不 一致  走了不少弯路.

所以  preserveInsertionOrder = true  是我的爱 .

Stringifier::stringify(array1,ssArray1);

----->

JSON\src\Stringifier.cpp:

else if ( any.type() == typeid(Array) )
{
const Array& a = any.extract<Array>();
a.stringify(out, indent == 0 ? 0 : indent, step);
}

--->

if ( any.type() == typeid(Object) )
{
const Object& o = any.extract<Object>();
o.stringify(out, indent == 0 ? 0 : indent, step);
}

--->

\JSON\src\Object.cpp:

void Object::stringify(std::ostream& out, unsigned int indent, int step) const
{
if (step < 0) step = indent;

if(!_preserveInsOrder)
doStringify(_values, out, indent, step);  // 不用代码添加顺序 ,则使用map窗口..jsoncpp也是map
else
doStringify(_keys, out, indent, step);//保留原有代码添加顺序, 则使用 std::deque<Dynamic::Var*> KeyPtrList
}

--->

\Poco\JSON\Object.h

template <typename C>
void doStringify(const C& container, std::ostream& out, unsigned int indent, unsigned int step) const
{
 ....

Stringifier::stringify(getKey(it), out); //这儿   getKey(it), 出了问题
out << ((indent > 0) ? " : " : ":");

Stringifier::stringify(getValue(it), out, indent + step, step);

...

}

\JSON\src\Object.cpp:

const std::string& Object::getKey(KeyPtrList::const_iterator& iter) const
{
ValueMap::const_iterator it = _values.begin();
ValueMap::const_iterator end = _values.end();
for (; it != end; ++it)
{
if (it->second == **iter) return it->first;
}

throw NotFoundException((*iter)->convert<std::string>());  //----->这儿报错
}

--->

Object.cpp中:

void Object::set(const std::string& key, const Dynamic::Var& value)
{
_values[key] = value;
if (_preserveInsOrder)
{
KeyPtrList::iterator it = _keys.begin();
KeyPtrList::iterator end = _keys.end();
for (; it != end; ++it)
{
if (key == **it) return;
}
_keys.push_back(&_values[key]);  //->这儿的内存地址发生了变化.
}
}

示例代码中:

array1.add(jObj2);-->Object 转到 (const Dynamic::Var& value)时

Foundation\include\Poco\Dynamic\Var.h:

Var(const T& val)
/// Creates the Var from the given value.
#ifdef POCO_NO_SOO
: _pHolder(new VarHolderImpl<T>(val))  --->>>发生了拷贝所以内存地址变化了.
{
}

后面在 https://github.com/pocoproject/poco/commit/3553a86d608321c1a06262c721aa766f1808cf2c

作者说

const std::string& Object::getKey(KeyPtrList::const_iterator& iter) const 中

if (&it->second == *iter) return it->first;

改成

if (it->second == **iter) return it->first;

注意 这个==是

poco开发版本地址:

https://github.com/pocoproject/poco/blob/develop/JSON/include/Poco/JSON/Object.h

https://github.com/pocoproject/poco/blob/develop/JSON/src/Object.cpp

以下只贴出了 重要更新的代码.

//
// Object.h如果是vs08的环境:

inline const Dynamic::Var& Object::getValue(KeyPtrList::const_iterator& it) const
{

return _values.at(**it);  //map.at 是C++ 11的标准,这儿不支持.

}

改成:

inline const Dynamic::Var& Object::getValue(KeyPtrList::const_iterator& it) const
{
const std::string & strKey=**it;
ValueMap ::const_iterator iter = _values.find(strKey);
if(iter!=_values.end())
return iter->second;

throw NotFoundException(strKey);
}

 

//
// Object.cpp
//
// $Id$
............void Object::stringify(std::ostream& out, unsigned int indent, int step) const
{
if (step < ) step = indent; if(!_preserveInsOrder)
doStringify(_values, out, indent, step);
else
doStringify(_keys, out, indent, step);
}const std::string& Object::getKey(KeyPtrList::const_iterator& iter) const
{
ValueMap::const_iterator it = _values.begin();
ValueMap::const_iterator end = _values.end();
for (; it != end; ++it)
{
if (it->first == **iter) return it->first;
} throw NotFoundException(**iter);
}void Object::set(const std::string& key, const Dynamic::Var& value)
{
std::pair<ValueMap::iterator, bool> ret = _values.insert(ValueMap::value_type(key, value));
if (_preserveInsOrder)
{
KeyPtrList::iterator it = _keys.begin();
KeyPtrList::iterator end = _keys.end();
for (; it != end; ++it)
{
if (key == **it) return;
}
_keys.push_back(&ret.first->first);
}
}

测试结果:

Object jObj2(true);//-------->use preserveInsertionOrder=truejObj2.set("car", "这是中文abc@qwe.com1231");
jObj2.set("baz", "fas");
jObj2.set("baz1", "fas");
jObj2.set("1baz11", "fas");
Poco::JSON::Array array1;
array1.add(jObj2);std::ostringstream oss122;
array1.stringify(oss122);
std::string fdsafsa=oss122.str();std::cout<<"array1="<<fdsafsa<<std::endl;
//输出:[{"car":"这是中文abc@qwe.com1231","baz":"fas","baz1":"fas","1baz11":"fas"}]

本以为到这儿就已经结束了....

然而我错了...

上篇附笔中:

poco json 中文字符，抛异常JSON Exception -->iconv 转换 备忘录。

http://www.cnblogs.com/bleachli/p/4646092.html

中的 suite()作下改变:

std::string suite()
{ std::string json = "";
//"{"
//"\"id\": 1123,"
//"\"jsonrpc\": \" 123.abc@hello.com,大圣归来.. \","
//"\"total\": 2,"
//"\"result\": "
//"["
//"{"
//"\"id\": null,"
//"\"picture\": \"http://placehold.it/32x32\","
//"\"name\": \"这是中文测试.Crossman\","
//"\"about\": \"《西游记之大圣归来》是根据中国传统神话故事进行拓展和演绎的3D动画电影.xxxx Consectetuer suscipit volutpat eros dolor .\","
//"\"friends\": "
//"["
//"{"
//"},"
//"{"
//"\"id\": 2,"
//"\"name\": \"Bailey Oldridge2\""
//"},"
//"{"
//"\"id\": 3,"
//"\"name\": \"Makayla Campbell3\""
//"}"
//"]"
//"},"
//"{"
//"\"id\": 2,"
//"\"picture\": \"http://placehold.it/32x32\","
//"\"name\": \"2中名 欢迎 \","
//"\"about\": \"2北京你好 dolor .\","
//"\"friends\": "
//"["
//"]"
//"}"
//"]"
//"}"; std::string strUtf8=GetJsonSource(true); Parser parser;
Var result; try
{
result = parser.parse(strUtf8);//json转换...
}
catch(JSONException& jsone)
{
std::cout << jsone.message() << std::endl;
return "result==NULL";
} Object::Ptr object = result.extract<Object::Ptr>();
int nObjectSize=object->size(); //assert(object->size() > 0);
DynamicStruct ds = *object; //遍历...
for(DynamicStruct::Iterator itBegin=ds.begin();itBegin!=ds.end();itBegin++)
{
//std::string strvalue=itBegin;
//Var var= itBegin->second;
//std::cout<<"type:"<<var.type()<<std::endl; std::cout<<"K:" << itBegin->first << " , value: " <<CMyCodeConvert::Utf8ToGb2312( itBegin->second.toString()) << std::endl;
} std::cout<<std::endl<<std::endl<<std::endl;
std::cout<<"+++++++++++++++++++++++++++++++++++++++++++++++++++"<<std::endl; json=""; std::string strlation1xxxx;
std::string strjstostring=strUtf8;
std::string strTemp;
std::string strKey; //std::string strKey="id"; //key 是否存在
strKey="id";
if(object->has(strKey))
{
strTemp=CMyCodeConvert::Utf8ToGb2312( object->get(strKey).toString());
std::cout<<"object->get("<<strKey<<")="<<strTemp<<std::endl;
} strKey="id2232";
if(object->has(strKey))
{
strTemp=CMyCodeConvert::Utf8ToGb2312( object->get(strKey).toString()); std::cout<<"object->get("<<strKey<<")="<<strTemp<<std::endl;
} strKey="jsonrpc";
if(object->has(strKey))
{
strTemp=CMyCodeConvert::Utf8ToGb2312( object->get(strKey).toString()); std::cout<<"object->get("<<strKey<<")="<<strTemp<<std::endl; std::string strxxx; std::cout<<"jsonrpc 编码:"<<std::endl;
std::string strxxxx=strTemp;
for(int nxxx=;nxxx<strxxxx.size();++nxxx)
{
unsigned char chTemp=strxxxx[nxxx];
std::string strTemp=Poco::format("%hX",(unsigned short )chTemp);
strTemp+=" ";
//std::cout<<strTemp;
} std::cout<<std::endl; //strjstostring+=strTemp; std::cout<<"object333->get("<<strKey<<")="<<strTemp<<std::endl;
} strKey="total";
if(object->has(strKey))
{
strTemp=CMyCodeConvert::Utf8ToGb2312( object->get(strKey).toString()); std::cout<<"object->get("<<strKey<<")="<<strTemp<<std::endl;
} strKey="result";
if(object->has(strKey))
{
strTemp=CMyCodeConvert::Utf8ToGb2312( object->get(strKey).toString()); std::cout<<"object->get("<<strKey<<")="<<strTemp<<std::endl; Var vResult=object->get("result"); Poco::JSON::Array::Ptr arrayResult = object->getArray("result");
Poco::JSON::Array::Ptr arr22222 = vResult.extract<Poco::JSON::Array::Ptr>(); Poco::Dynamic::Array dsarrayResult = *arrayResult; std::cout<<"arr22222->size()"<<arr22222->size()<<std::endl;
std::cout<<"arrayResult->size()"<<arrayResult->size()<<std::endl;
std::cout<<"arrayResult->size()"<<dsarrayResult.size()<<std::endl; for(int nIndex=;nIndex<arrayResult->size();++nIndex)
{
Object::Ptr object = arrayResult->getObject(nIndex); strKey="id";
if(object->has(strKey))
{
strTemp="";
if(!object->get(strKey).isEmpty())
{
strTemp=CMyCodeConvert::Utf8ToGb2312( object->get(strKey).toString()); std::cout<<"object->get("<<strKey<<")="<<strTemp<<std::endl;
} } strKey="picture";
if(object->has(strKey))
{
strTemp=CMyCodeConvert::Utf8ToGb2312( object->get(strKey).toString()); std::cout<<"object->get("<<strKey<<")="<<strTemp<<std::endl;
} strKey="name";
if(object->has(strKey))
{
strTemp=CMyCodeConvert::Utf8ToGb2312( object->get(strKey).toString()); std::cout<<"object->get("<<strKey<<")="<<strTemp<<std::endl;
} strKey="about";
if(object->has(strKey))
{
strTemp=CMyCodeConvert::Utf8ToGb2312( object->get(strKey).toString()); std::cout<<"object->get("<<strKey<<")="<<strTemp<<std::endl;
} strKey="friends";
if(object->has(strKey))
{
strTemp=object->get(strKey).toString(); std::cout<<"object->get("<<strKey<<")="<<strTemp<<std::endl; Poco::JSON::Array::Ptr arrayFriends = object->getArray(strKey);
for(int nIndex=;nIndex<arrayFriends->size();++nIndex)
{
Object::Ptr objectFriends = arrayFriends->getObject(nIndex);
DynamicStruct dsTemp = *objectFriends; for(DynamicStruct::Iterator itBegin=dsTemp.begin();itBegin!=dsTemp.end();itBegin++)
{
std::cout<<"K:" << itBegin->first << " , value: " << CMyCodeConvert::Utf8ToGb2312(itBegin->second.toString() )<< std::endl;
} }
} std::cout<<std::endl<<std::endl<<std::endl;
std::cout<<"+++++++++++++++++++++++++++++++++++++++++++++++++++"<<std::endl; std::cout<<std::endl<<std::endl<<std::endl; } } return strjstostring;
}

GetJsonSource()代码:

std::string GetJsonSource(bool bUtf8)
{
bool bIspreserveInsertionOrder=true; Object jObjRoot(bIspreserveInsertionOrder);//-------->use preserveInsertionOrder=true jObjRoot.set("id", );
jObjRoot.set("car", ("这是中文abc@qwe.com1231,123.abc@hello.com,大圣归来..") );
jObjRoot.set("total", ); Poco::JSON::Array arrayResult; for(int nIndex=;nIndex<;nIndex++)
{
Object jArrayObj(bIspreserveInsertionOrder);
jArrayObj.set("id", nIndex);
jArrayObj.set("picture",("http://placehold.it/111.abc.") );
jArrayObj.set("name",("这是中文测试.Crossman.") );
jArrayObj.set("about",("《西游记之大圣归来》是根据中国传统神话故事进行拓展和演绎的3D动画电影.xxxx Consectetuer suscipit volutpat eros dolor .") ); Poco::JSON::Array arrayFriends;
for(int i=;i<;++i)
{
Object jarrayFriendsObj(bIspreserveInsertionOrder);
jarrayFriendsObj.set("id", i);
jarrayFriendsObj.set("name", (Poco::format("name%d,这是无可奈何花落去!",i))); arrayFriends.add(jarrayFriendsObj);
} jArrayObj.set("friends",arrayFriends); arrayResult.add(jArrayObj); } jObjRoot.set("result",arrayResult); std::string strObjRoot;
std::ostringstream ojObjRoot;
//
//bIspreserveInsertionOrder =false时程序正常运行.
//bIspreserveInsertionOrder =true 时程序出错
//Poco\JSON\Object.cpp
//const std::string& Object::getKey(KeyPtrList::const_iterator& iter) const
//iter is null.
//产生memcpy 错误..
//
jObjRoot.stringify(ojObjRoot);//

strObjRoot=ojObjRoot.str(); if(bUtf8)
strObjRoot=CMyCodeConvert::Gb2312ToUtf8(strObjRoot); //std::string strGbkTemp=CMyCodeConvert::Utf8ToGb2312(strObjRoot);
return strObjRoot;}

原因是

typedef std::deque<const std::string*> KeyPtrList; 这儿是指针地址,临时变量内容已经over了.

so...再改改代码:

poco\JSON\include\Poco\JSON\Object.h 改动部分

typedef std::deque< std::string> KeyPtrList;inline const Dynamic::Var& Object::getValue(KeyPtrList::const_iterator& it) const
{
const std::string & strKey=*it;
ValueMap ::const_iterator iter = _values.find(strKey);
if(iter!=_values.end())
return iter->second;throw NotFoundException(strKey);
}

poco\JSON\src\Object.cpp 中改动部分:

const std::string& Object::getKey(KeyPtrList::const_iterator& iter) const
{
ValueMap::const_iterator it = _values.begin();
ValueMap::const_iterator end = _values.end();
for (; it != end; ++it)
{
if (it->first == *iter) return it->first;
}throw NotFoundException(*iter);
}void Object::set(const std::string& key, const Dynamic::Var& value)
{
std::pair<ValueMap::iterator, bool> ret = _values.insert(ValueMap::value_type(key, value));
if (_preserveInsOrder)
{
KeyPtrList::iterator it = _keys.begin();
KeyPtrList::iterator end = _keys.end();
for (; it != end; ++it)
{
if (key == *it) return;
}
_keys.push_back(ret.first->first);
}
}

GetJsonSource()输出的结果可在 http://www.bejson.com/  中校验.

-_- 终于成功了...

把代码在debian下编译看下 通过http访问结果:

然而作者又回复了我:

Don't nest objects and arrays by value, it won't work properly - use smart pointers (Object::Ptr and Array::Ptr). See this issue for explanation.

object.h,object.cpp还是用作者的code.

poco开发版本地址:

https://github.com/pocoproject/poco/blob/develop/JSON/include/Poco/JSON/Object.h

https://github.com/pocoproject/poco/blob/develop/JSON/src/Object.cpp

然后测试代码如下:

std::string GetJsonSource(bool bUtf8)
{
bool bIspreserveInsertionOrder=true; //Object result(bIspreserveInsertionOrder);//-------->use preserveInsertionOrder=true //result.set("id", 1123); //Poco::JSON::Object::Ptr inner= new Poco::JSON::Object(bIspreserveInsertionOrder) ;
//inner->set("some_number", 5);
//inner->set("some_string", "xyz");
//std::string key = "new_object";
//result.set(key, inner); // OK
////assert (result.isObject()); // OK
// //std::string strOxxxxx;
//std::ostringstream oxxxxx;
//result.stringify(oxxxxx);//
//strOxxxxx=oxxxxx.str(); //return ""; Object jObjRoot(bIspreserveInsertionOrder);//-------->use preserveInsertionOrder=true jObjRoot.set("id", );
jObjRoot.set("car", ("这是中文abc@qwe.com1231,123.abc@hello.com,大圣归来..") );
jObjRoot.set("total", ); //Poco::JSON::Array arrayResult;
Poco::JSON::Array::Ptr parrayResult= new Poco::JSON::Array() ;
for(int nIndex=;nIndex<;nIndex++)
{
Poco::JSON::Object::Ptr pjArrayObj= new Poco::JSON::Object(bIspreserveInsertionOrder) ;
//Object jArrayObj(bIspreserveInsertionOrder);
pjArrayObj->set("id", nIndex);
pjArrayObj->set("picture",("http://placehold.it/111.abc.") );
pjArrayObj->set("name",("这是中文测试.Crossman.") );
pjArrayObj->set("about",("《西游记之大圣归来》是根据中国传统神话故事进行拓展和演绎的3D动画电影.xxxx Consectetuer suscipit volutpat eros dolor .") ); Poco::JSON::Array::Ptr parrayFriends= new Poco::JSON::Array() ;
//Poco::JSON::Array arrayFriends;
for(int i=;i<;++i)
{
Poco::JSON::Object::Ptr pjarrayFriendsObj= new Poco::JSON::Object(bIspreserveInsertionOrder) ;
//Object jarrayFriendsObj(bIspreserveInsertionOrder);
pjarrayFriendsObj->set("id", i);
pjarrayFriendsObj->set("name", (Poco::format("name%d,这是无可奈何花落去!",i))); parrayFriends->add(pjarrayFriendsObj);
} pjArrayObj->set("friends",parrayFriends); parrayResult->add(pjArrayObj); } jObjRoot.set("result",parrayResult); std::string strObjRoot;
std::ostringstream ojObjRoot;
////
jObjRoot.stringify(ojObjRoot);// strObjRoot=ojObjRoot.str(); if(bUtf8)
strObjRoot=CMyCodeConvert::Gb2312ToUtf8(strObjRoot); //std::string strGbkTemp=CMyCodeConvert::Utf8ToGb2312(strObjRoot);
return strObjRoot;}

这个问题终于得到解决...

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