Jsonlizer，一个把C++各类数据转成 Json 结构体的玩意儿

        这段时间突发奇想，觉得可以弄一个Json和C++各种数据类型互转的工具，因为Json在进行数据储存的时候，有一些先天的优势，传统的C++的序列化方式是将数据序列化到流数据里面，而流数据是典型的串行结构（或则说是一维结构），因此，流数据对数据的位置特别的敏感，一旦序列化的元素有调整，就会导致原来存储的流数据完全失效。这一点在游戏开发时非常的麻烦，我们不得不将各个接口进行拆分，让接口对应其独自的流数据，做到局部的隔离。但是这个办法也不是万能，因为，一旦接口内某些元素顺序因为开始时过于简单而并没有做拆分时，隐藏的风险种子就种下了。随着时间推移，一旦需要更改这些元素时，就会发现被锁死了手脚！

        Json具有结构化的特征，涵盖了原型，数组，对象等数据类型，用来做存储是非常理想的，如果项目中存储的数据用Json存储，然后再序列化到二进制流数据内，这样似乎就结合了两者的优点，结合了速度和可扩展性。而我自己写的CJson类本身就是可以序列化到流数据的。而且从流数据恢复的速度远比解析Json字符串的速度快几倍，那么现在欠缺的就是如何将C++数据转换成CJson类。

        思考了一段时间，我意识到 Jsonlizer 和 Serializer 有本质的区别，一个是构建层次结构，一个是构建一维结构，我本来想尽可能的复用Serializer的代码，但我意识到，这是不可能的。我能利用的，可能仅仅是一部分最基本的，被称为 trait 模板代码。

        而想复用Serialize函数的想法是不可能的。毕竟一个是结构化的数据，一个是一维数据。于是我改变了策略，重新构造了Jsonlizer。首先要做的是重写整个Jsonlizer的模板代码。这部分代码非常的关键，就是用于识别C++的各类数据。

这几个文件的代码如下：

#ifndef TAGPJSONLIZERRIMITIVE_H
#define TAGPJSONLIZERRIMITIVE_H
//Begin section for file tagJsonPrimitive.h
//TODO: Add definitions that you want preserved
//End section for file tagJsonPrimitive.hnamespace atom
{//@generated "UML to C++ (com.ibm.xtools.transform.uml2.cpp.CPPTransformation)"template <class A, class T, bool save>struct tagJsonPrimitive{//Begin section for si::tagJsonPrimitive//TODO: Add attributes that you want preserved//End section for si::tagJsonPrimitivepublic://@generated "UML to C++ (com.ibm.xtools.transform.uml2.cpp.CPPTransformation)"inline static void Invoke(A & node, T & t){//TODO Auto-generated method stubnode.Bind( t );}};  //end struct tagJsonPrimitive} // end namespace atom#endif

原型非常简单，没什么好说的。

#ifndef TAGJSONLIZERINVALID_H
#define TAGJSONLIZERINVALID_H
//Begin section for file tagJsonInvalid.h
//TODO: Add definitions that you want preserved
//End section for file tagJsonInvalid.hnamespace atom
{//@generated "UML to C++ (com.ibm.xtools.transform.uml2.cpp.CPPTransformation)"template <class A, class T, bool save>struct tagJsonInvalid{//Begin section for si::tagJsonInvalid//TODO: Add attributes that you want preserved//End section for si::tagJsonInvalidpublic://@generated "UML to C++ (com.ibm.xtools.transform.uml2.cpp.CPPTransformation)"inline static void Invoke(A & n, T & t){UNREFERENCED_PARAMETER(n);UNREFERENCED_PARAMETER(t);//TODO Auto-generated method stubprintf( "Jsonlization NOT support these keyword: mutable\n" );}};  //end struct tagJsonInvalid} // end namespace atom#endif

 不支持的类型就是输出提示。

#ifndef TAGJSONLIZERARRAY_H
#define TAGJSONLIZERARRAY_H
//Begin section for file tagJsonArray.h
//TODO: Add definitions that you want preserved
//End section for file tagJsonArray.h
#include "../../../serialization/trait/array_trait.h"namespace atom
{//@generated "UML to C++ (com.ibm.xtools.transform.uml2.cpp.CPPTransformation)"template <class A, class T, bool save>struct tagJsonArray{//Begin section for si::tagJsonArray//TODO: Add attributes that you want preserved//End section for si::tagJsonArraypublic://@generated "UML to C++ (com.ibm.xtools.transform.uml2.cpp.CPPTransformation)"inline static void Invoke(A & jr, T & t){//TODO Auto-generated method stub// 读取或写入数组的长度；U32 bound = static_cast<U32>( array_trait<T>::bound );U32 limit = bound;CJson node = jr.GetCurrentNode();if( save == false ) {bound = static_cast<U32>( node.Length() );}// 确认数组的长度是否越界；bound = atom_min( bound, limit );// 读取或写入数组的元素；for( size_t i = 0; i < bound; ++ i ){CJson child( true );if( save == false ) {child = node[i];}jr.Push( child );jr.Bind( t[i] );jr.Pop();if( save ) {node.Push( child );}}}};  //end struct tagJsonArray} // end namespace atom#endif

        数组开始有点东西了，其中能看到 Jsonlizer 有几个函数：Push，Pop，GetCurrentNode。这几个函数其实就是维护一个节点堆栈，堆栈内放入的是被操作的节点列表。顶部的节点就是最新需要被操作的节点。

#ifndef TAGJSONLIZERCLASS_H
#define TAGJSONLIZERCLASS_H
//Begin section for file tagJsonClass.h
//TODO: Add definitions that you want preserved
//End section for file tagJsonClass.h// 为序列化类而特别准备的缺省模板函数。
template<class A, class T>
inline void Jsonlize(A & jr, T & t, bool save)
{t.Jsonlize( jr, save );
}namespace atom
{//@generated "UML to C++ (com.ibm.xtools.transform.uml2.cpp.CPPTransformation)"template <class A, class T, bool save>struct tagJsonClass{//Begin section for si::tagJsonClass//TODO: Add attributes that you want preserved//End section for si::tagJsonClasspublic://@generated "UML to C++ (com.ibm.xtools.transform.uml2.cpp.CPPTransformation)"inline static void Invoke(A & jr, T & t){//TODO Auto-generated method stubJsonlize( jr, t, save );}};  //end struct tagJsonClass} // end namespace atom#endif

 类的代码其实不复杂，因为类的代码需要用户自己完成。

#ifndef TAGJSONLIZER_H
#define TAGJSONLIZER_H
//Begin section for file tagJsonlizer.h
//TODO: Add definitions that you want preserved
//End section for file tagJsonlizer.h#include "../../../serialization/trait/is_primitive.h"
#include "../../../serialization/trait/is_array.h"
#include "../../../serialization/trait/is_class.h"
#include "../../../serialization/trait/is_pointer.h"
#include "../../../serialization/trait/if_else.h"
#include "../../../serialization/trait/degradation_trait.h"
#include "tagJsonPrimitive.h"
#include "tagJsonArray.h" 
#include "tagJsonClass.h"
#include "tagJsonInvalid.h"namespace atom
{//@generated "UML to C++ (com.ibm.xtools.transform.uml2.cpp.CPPTransformation)"template <class A, class T, bool B>struct tagJsonlizer{//Begin section for si::tagJsonlizer//TODO: Add attributes that you want preserved//End section for si::tagJsonlizerpublic://@generated "UML to C++ (com.ibm.xtools.transform.uml2.cpp.CPPTransformation)"inline static void Jsonlize(A & json, T & data){//TODO Auto-generated method stubtypedef typename degradation_trait<T>::type C;typedef typenameif_else<is_array<C>::value,tagJsonArray<A, C, B>, typenameif_else<is_class<C>::value, tagJsonClass<A, C, B>, typenameif_else<is_primitive<C>::value,tagJsonPrimitive<A, C, B>,tagJsonInvalid  <A, C, B>>::type >::type >::type Invoker;Invoker::Invoke( json, type_cast(data) );}};  //end struct tagJsonlizer} // end namespace atom#endif

这个就是Jsonlizer模板的入口了，接下来就是导入，导出类的代码。

#ifndef CJSONIMPORTER_H
#define CJSONIMPORTER_H
//Begin section for file CJsonImporter.h
//TODO: Add definitions that you want preserved
//End section for file CJsonImporter.h
#include "../../../Common.h"
#include "../../../interface/IEmbedInterface.h"
#include "../../../interface/IInterface.h"
#include "../../../interface/IJsonlizerRoot.h"
#include "../../../enumeration/INTERFACE_ID.h"
#include "../../../os/character/CCharset.h"
#include "../../stl/a_string.h"
#include "../../stl/a_wstring.h"
#include "../../hex/hex.h"
#include "../../tool/CInterface.h"
#include "tagJsonlizer.h"namespace atom
{//@generated "UML to C++ (com.ibm.xtools.transform.uml2.cpp.CPPTransformation)"class CJsonImporter : public IEmbedInterface{//Begin section for atom::CJsonImporter//TODO: Add attributes that you want preserved//End section for atom::CJsonImporterprivate://@generated "UML to C++ (com.ibm.xtools.transform.uml2.cpp.CPPTransformation)"IInterface * nest;#ifdef _SHIPPING_//@generated "UML to C++ (com.ibm.xtools.transform.uml2.cpp.CPPTransformation)"IReferencedInterface * cast;#endifpublic://@generated "UML to C++ (com.ibm.xtools.transform.uml2.cpp.CPPTransformation)"CJsonImporter(); //@generated "UML to C++ (com.ibm.xtools.transform.uml2.cpp.CPPTransformation)"virtual ~CJsonImporter(); //@generated "UML to C++ (com.ibm.xtools.transform.uml2.cpp.CPPTransformation)"virtual int IncRef(); //@generated "UML to C++ (com.ibm.xtools.transform.uml2.cpp.CPPTransformation)"virtual int DecRef(); //@generated "UML to C++ (com.ibm.xtools.transform.uml2.cpp.CPPTransformation)"virtual int GetRef(); //@generated "UML to C++ (com.ibm.xtools.transform.uml2.cpp.CPPTransformation)"virtual IInterface * QueryInterface(U32 iid); //@generated "UML to C++ (com.ibm.xtools.transform.uml2.cpp.CPPTransformation)"virtual void SetNest(IInterface * nest); //@generated "UML to C++ (com.ibm.xtools.transform.uml2.cpp.CPPTransformation)"inline CJson GetCurrentNode(){// TODO Auto-generated method stubCJson result;CInterface<IJsonlizerRoot> root;if( root.Mount(this, IID_JSONLIZER_ROOT) ) {result = root -> GetCurrentNode();}return result;}//@generated "UML to C++ (com.ibm.xtools.transform.uml2.cpp.CPPTransformation)"inline void Push(CJson & node){// TODO Auto-generated method stubCInterface<IJsonlizerRoot> root;if( root.Mount(this, IID_JSONLIZER_ROOT) ) {root -> Push( node );}}//@generated "UML to C++ (com.ibm.xtools.transform.uml2.cpp.CPPTransformation)"inline void Pop(){// TODO Auto-generated method stubCInterface<IJsonlizerRoot> root;if( root.Mount(this, IID_JSONLIZER_ROOT) ) {root -> Pop();}}//@generated "UML to C++ (com.ibm.xtools.transform.uml2.cpp.CPPTransformation)"inline void Bind(bool & value){// TODO Auto-generated method stubCInterface<IJsonlizerRoot> root;if( root.Mount(this, IID_JSONLIZER_ROOT) ){CJson node = root -> GetCurrentNode();value = static_cast<bool>( node );}}//@generated "UML to C++ (com.ibm.xtools.transform.uml2.cpp.CPPTransformation)"inline void Bind(char & value){// TODO Auto-generated method stubCInterface<IJsonlizerRoot> root;if( root.Mount(this, IID_JSONLIZER_ROOT) ){CJson node = root -> GetCurrentNode();value = static_cast<U08>( node );}}//@generated "UML to C++ (com.ibm.xtools.transform.uml2.cpp.CPPTransformation)"inline void Bind(I08 & value){// TODO Auto-generated method stubCInterface<IJsonlizerRoot> root;if( root.Mount(this, IID_JSONLIZER_ROOT) ){CJson node = root -> GetCurrentNode();value = static_cast<I08>( node );}}//@generated "UML to C++ (com.ibm.xtools.transform.uml2.cpp.CPPTransformation)"inline void Bind(I16 & value){// TODO Auto-generated method stubCInterface<IJsonlizerRoot> root;if( root.Mount(this, IID_JSONLIZER_ROOT) ){CJson node = root -> GetCurrentNode();value = static_cast<I16>( node );}}//@generated "UML to C++ (com.ibm.xtools.transform.uml2.cpp.CPPTransformation)"inline void Bind(I32 & value){// TODO Auto-generated method stubCInterface<IJsonlizerRoot> root;if( root.Mount(this, IID_JSONLIZER_ROOT) ){CJson node = root -> GetCurrentNode();value = static_cast<I32>( node );}}//@generated "UML to C++ (com.ibm.xtools.transform.uml2.cpp.CPPTransformation)"inline void Bind(I64 & value){// TODO Auto-generated method stubCInterface<IJsonlizerRoot> root;if( root.Mount(this, IID_JSONLIZER_ROOT) ){CJson node = root -> GetCurrentNode();value = static_cast<I64>( node );}}//@generated "UML to C++ (com.ibm.xtools.transform.uml2.cpp.CPPTransformation)"inline void Bind(U08 & value){// TODO Auto-generated method stubCInterface<IJsonlizerRoot> root;if( root.Mount(this, IID_JSONLIZER_ROOT) ){CJson node = root -> GetCurrentNode();value = static_cast<U08>( node );}}//@generated "UML to C++ (com.ibm.xtools.transform.uml2.cpp.CPPTransformation)"inline void Bind(U16 & value){// TODO Auto-generated method stubCInterface<IJsonlizerRoot> root;if( root.Mount(this, IID_JSONLIZER_ROOT) ){CJson node = root -> GetCurrentNode();value = static_cast<U16>( node );}}//@generated "UML to C++ (com.ibm.xtools.transform.uml2.cpp.CPPTransformation)"inline void Bind(U32 & value){// TODO Auto-generated method stubCInterface<IJsonlizerRoot> root;if( root.Mount(this, IID_JSONLIZER_ROOT) ){CJson node = root -> GetCurrentNode();value = static_cast<U32>( node );}}//@generated "UML to C++ (com.ibm.xtools.transform.uml2.cpp.CPPTransformation)"inline void Bind(U64 & value){// TODO Auto-generated method stubCInterface<IJsonlizerRoot> root;if( root.Mount(this, IID_JSONLIZER_ROOT) ){CJson node = root -> GetCurrentNode();value = static_cast<U64>( node );}}//@generated "UML to C++ (com.ibm.xtools.transform.uml2.cpp.CPPTransformation)"inline void Bind(float & value){// TODO Auto-generated method stubCInterface<IJsonlizerRoot> root;if( root.Mount(this, IID_JSONLIZER_ROOT) ){CJson node = root -> GetCurrentNode();value = static_cast<float>( node );}}//@generated "UML to C++ (com.ibm.xtools.transform.uml2.cpp.CPPTransformation)"inline void Bind(double & value){// TODO Auto-generated method stubCInterface<IJsonlizerRoot> root;if( root.Mount(this, IID_JSONLIZER_ROOT) ){CJson node = root -> GetCurrentNode();value = static_cast<double>( node );}}//@generated "UML to C++ (com.ibm.xtools.transform.uml2.cpp.CPPTransformation)"inline void Bind(a_string & value){// TODO Auto-generated method stubCInterface<IJsonlizerRoot> root;if( root.Mount(this, IID_JSONLIZER_ROOT) ){CJson node = root -> GetCurrentNode();value = static_cast<a_string>( node );}}//@generated "UML to C++ (com.ibm.xtools.transform.uml2.cpp.CPPTransformation)"inline void Bind(a_wstring & value){// TODO Auto-generated method stubCInterface<IJsonlizerRoot> root;if( root.Mount(this, IID_JSONLIZER_ROOT) ){CJson node = root -> GetCurrentNode();a_string text = node;CCharset charset( text.c_str() );value = charset.FromUtf8.ToUnicode;}}//@generated "UML to C++ (com.ibm.xtools.transform.uml2.cpp.CPPTransformation)"inline void Bind(void * buffer, U64 length){// TODO Auto-generated method stubif( buffer && length ){CInterface<IJsonlizerRoot> root;if( root.Mount(this, IID_JSONLIZER_ROOT) ){CJson node = root -> GetCurrentNode();a_string text = node;FromHex( text, buffer, length );}}}//@generated "UML to C++ (com.ibm.xtools.transform.uml2.cpp.CPPTransformation)"template<class T>inline void Bind(T & value){//TODO Auto-generated method stubtagJsonlizer<CJsonImporter, T, false>::Jsonlize( *this, value );}//@generated "UML to C++ (com.ibm.xtools.transform.uml2.cpp.CPPTransformation)"template<class T>inline void Bind(const char * name, T & value){//TODO Auto-generated method stubif( name ){CInterface<IJsonlizerRoot> root;if( root.Mount(this, IID_JSONLIZER_ROOT) ){CJson node  = root -> GetCurrentNode();CJson child = node[name];root -> Push( child );Bind( value );root -> Pop();}}}};  //end class CJsonImporter} //end namespace atom#endif

#ifndef CJSONEXPORTER_H
#define CJSONEXPORTER_H
//Begin section for file CJsonExporter.h
//TODO: Add definitions that you want preserved
//End section for file CJsonExporter.h
#include "../../../Common.h"
#include "../../../interface/IEmbedInterface.h"
#include "../../../interface/IInterface.h"
#include "../../../interface/IJsonlizerRoot.h"
#include "../../../enumeration/INTERFACE_ID.h"
#include "../../../os/character/CCharset.h"
#include "../../stl/a_string.h"
#include "../../stl/a_wstring.h"
#include "../../hex/hex.h"
#include "../../tool/CInterface.h"
#include "tagJsonlizer.h"namespace atom
{//@generated "UML to C++ (com.ibm.xtools.transform.uml2.cpp.CPPTransformation)"class CJsonExporter : public IEmbedInterface{//Begin section for atom::CJsonExporter//TODO: Add attributes that you want preserved//End section for atom::CJsonExporterprivate://@generated "UML to C++ (com.ibm.xtools.transform.uml2.cpp.CPPTransformation)"IInterface * nest;#ifdef _SHIPPING_//@generated "UML to C++ (com.ibm.xtools.transform.uml2.cpp.CPPTransformation)"IReferencedInterface * cast;#endifpublic://@generated "UML to C++ (com.ibm.xtools.transform.uml2.cpp.CPPTransformation)"CJsonExporter(); //@generated "UML to C++ (com.ibm.xtools.transform.uml2.cpp.CPPTransformation)"virtual ~CJsonExporter(); //@generated "UML to C++ (com.ibm.xtools.transform.uml2.cpp.CPPTransformation)"virtual int IncRef(); //@generated "UML to C++ (com.ibm.xtools.transform.uml2.cpp.CPPTransformation)"virtual int DecRef(); //@generated "UML to C++ (com.ibm.xtools.transform.uml2.cpp.CPPTransformation)"virtual int GetRef(); //@generated "UML to C++ (com.ibm.xtools.transform.uml2.cpp.CPPTransformation)"virtual IInterface * QueryInterface(U32 iid); //@generated "UML to C++ (com.ibm.xtools.transform.uml2.cpp.CPPTransformation)"virtual void SetNest(IInterface * nest); //@generated "UML to C++ (com.ibm.xtools.transform.uml2.cpp.CPPTransformation)"inline CJson GetCurrentNode(){// TODO Auto-generated method stubCJson result;CInterface<IJsonlizerRoot> root;if( root.Mount(this, IID_JSONLIZER_ROOT) ) {result = root -> GetCurrentNode();}return result;}//@generated "UML to C++ (com.ibm.xtools.transform.uml2.cpp.CPPTransformation)"inline void Push(CJson & node){// TODO Auto-generated method stubCInterface<IJsonlizerRoot> root;if( root.Mount(this, IID_JSONLIZER_ROOT) ) {root -> Push( node );}}//@generated "UML to C++ (com.ibm.xtools.transform.uml2.cpp.CPPTransformation)"inline void Pop(){// TODO Auto-generated method stubCInterface<IJsonlizerRoot> root;if( root.Mount(this, IID_JSONLIZER_ROOT) ) {root -> Pop();}}//@generated "UML to C++ (com.ibm.xtools.transform.uml2.cpp.CPPTransformation)"inline void Bind(bool & value){//TODO Auto-generated method stubCInterface<IJsonlizerRoot> root;if( root.Mount(this, IID_JSONLIZER_ROOT) ){CJson node = root -> GetCurrentNode();node = value;}}//@generated "UML to C++ (com.ibm.xtools.transform.uml2.cpp.CPPTransformation)"inline void Bind(char & value){//TODO Auto-generated method stubCInterface<IJsonlizerRoot> root;if( root.Mount(this, IID_JSONLIZER_ROOT) ){CJson node = root -> GetCurrentNode();node = value;}}//@generated "UML to C++ (com.ibm.xtools.transform.uml2.cpp.CPPTransformation)"inline void Bind(I08 & value){//TODO Auto-generated method stubCInterface<IJsonlizerRoot> root;if( root.Mount(this, IID_JSONLIZER_ROOT) ){CJson node = root -> GetCurrentNode();node = value;}}//@generated "UML to C++ (com.ibm.xtools.transform.uml2.cpp.CPPTransformation)"inline void Bind(I16 & value) {//TODO Auto-generated method stubCInterface<IJsonlizerRoot> root;if( root.Mount(this, IID_JSONLIZER_ROOT) ){CJson node = root -> GetCurrentNode();node = value;}}//@generated "UML to C++ (com.ibm.xtools.transform.uml2.cpp.CPPTransformation)"inline void Bind(I32 & value){//TODO Auto-generated method stubCInterface<IJsonlizerRoot> root;if( root.Mount(this, IID_JSONLIZER_ROOT) ){CJson node = root -> GetCurrentNode();node = value;}}//@generated "UML to C++ (com.ibm.xtools.transform.uml2.cpp.CPPTransformation)"inline void Bind(I64 & value){//TODO Auto-generated method stubCInterface<IJsonlizerRoot> root;if( root.Mount(this, IID_JSONLIZER_ROOT) ){CJson node = root -> GetCurrentNode();node = value;}}//@generated "UML to C++ (com.ibm.xtools.transform.uml2.cpp.CPPTransformation)"inline void Bind(U08 & value){//TODO Auto-generated method stubCInterface<IJsonlizerRoot> root;if( root.Mount(this, IID_JSONLIZER_ROOT) ){CJson node = root -> GetCurrentNode();node = value;}}//@generated "UML to C++ (com.ibm.xtools.transform.uml2.cpp.CPPTransformation)"inline void Bind(U16 & value){//TODO Auto-generated method stubCInterface<IJsonlizerRoot> root;if( root.Mount(this, IID_JSONLIZER_ROOT) ){CJson node = root -> GetCurrentNode();node = value;}}//@generated "UML to C++ (com.ibm.xtools.transform.uml2.cpp.CPPTransformation)"inline void Bind(U32 & value){//TODO Auto-generated method stubCInterface<IJsonlizerRoot> root;if( root.Mount(this, IID_JSONLIZER_ROOT) ){CJson node = root -> GetCurrentNode();node = value;}}//@generated "UML to C++ (com.ibm.xtools.transform.uml2.cpp.CPPTransformation)"inline void Bind(U64 & value){//TODO Auto-generated method stubCInterface<IJsonlizerRoot> root;if( root.Mount(this, IID_JSONLIZER_ROOT) ){CJson node = root -> GetCurrentNode();node = value;}}//@generated "UML to C++ (com.ibm.xtools.transform.uml2.cpp.CPPTransformation)"inline void Bind(float & value){//TODO Auto-generated method stubCInterface<IJsonlizerRoot> root;if( root.Mount(this, IID_JSONLIZER_ROOT) ){CJson node = root -> GetCurrentNode();node = value;}}//@generated "UML to C++ (com.ibm.xtools.transform.uml2.cpp.CPPTransformation)"inline void Bind(double & value){//TODO Auto-generated method stubCInterface<IJsonlizerRoot> root;if( root.Mount(this, IID_JSONLIZER_ROOT) ){CJson node = root -> GetCurrentNode();node = value;}}//@generated "UML to C++ (com.ibm.xtools.transform.uml2.cpp.CPPTransformation)"inline void Bind(const char * value) {//TODO Auto-generated method stubif( value ){CInterface<IJsonlizerRoot> root;if( root.Mount(this, IID_JSONLIZER_ROOT) ){CJson node = root -> GetCurrentNode();node = value;}}}//@generated "UML to C++ (com.ibm.xtools.transform.uml2.cpp.CPPTransformation)"inline void Bind(const wchar_t * value){//TODO Auto-generated method stubif( value ){CInterface<IJsonlizerRoot> root;if( root.Mount(this, IID_JSONLIZER_ROOT) ){CJson node = root -> GetCurrentNode();CCharset charset( value );a_string text = charset.ToUtf8;node = text.c_str();}}}//@generated "UML to C++ (com.ibm.xtools.transform.uml2.cpp.CPPTransformation)"inline void Bind(a_string & value) {//TODO Auto-generated method stubCInterface<IJsonlizerRoot> root;if( root.Mount(this, IID_JSONLIZER_ROOT) ){CJson node = root -> GetCurrentNode();node = value.c_str();}}//@generated "UML to C++ (com.ibm.xtools.transform.uml2.cpp.CPPTransformation)"inline void Bind(a_wstring & value){//TODO Auto-generated method stubCInterface<IJsonlizerRoot> root;if( root.Mount(this, IID_JSONLIZER_ROOT) ){CJson node = root -> GetCurrentNode();CCharset charset( value.c_str() );a_string text = charset.ToUtf8;node = text.c_str();}}//@generated "UML to C++ (com.ibm.xtools.transform.uml2.cpp.CPPTransformation)"inline void Bind(void * buffer, U64 length){//TODO Auto-generated method stubif( buffer && length ){CInterface<IJsonlizerRoot> root;if( root.Mount(this, IID_JSONLIZER_ROOT) ){a_string text = ToHex( buffer, length );CJson node = root -> GetCurrentNode();node = text.c_str();}}}//@generated "UML to C++ (com.ibm.xtools.transform.uml2.cpp.CPPTransformation)"template<class T>inline void Bind(T & value){//TODO Auto-generated method stubtagJsonlizer<CJsonExporter, T, true>::Jsonlize( * this, value );}//@generated "UML to C++ (com.ibm.xtools.transform.uml2.cpp.CPPTransformation)"template<class T>inline void Bind(const T & value){//TODO Auto-generated method stubBind( const_cast<T &>(value) );}//@generated "UML to C++ (com.ibm.xtools.transform.uml2.cpp.CPPTransformation)"template<class T>inline void Bind(const char * name, T & value){//TODO Auto-generated method stubif( name ){CInterface<IJsonlizerRoot> root;if( root.Mount(this, IID_JSONLIZER_ROOT) ){CJson node  = root -> GetCurrentNode();CJson child = node[name];root -> Push( child );Bind( value );root -> Pop();}}}//@generated "UML to C++ (com.ibm.xtools.transform.uml2.cpp.CPPTransformation)"template<class T>inline void Bind(const char * name, const T & value){//TODO Auto-generated method stubBind( name, const_cast<T &>(value) );}};  //end class CJsonExporter} //end namespace atom#endif

导入导出的类有一个特殊的函数：

inline void Bind(const char * name, T & value)

这个函数带了一个name的参数，其实就是针对类的成员变量而设的。

#ifndef CJSONLIZER_H
#define CJSONLIZER_H
//Begin section for file CJsonlizer.h
//TODO: Add definitions that you want preserved
//End section for file CJsonlizer.h
#include "../../../Common.h"
#include "CJsonExporter.h"
#include "CJsonImporter.h"
#include "CJsonlizerRoot.h"
#include "../CJson.h"inline const char * last_dot(const char * value)
{const char * result(value);if( value ) {for( ;; ++ value ){if( *value == 0 ) break;if( *value == '.' ) {result = value + 1;}}}    return result;
}#define JKV(V) make_pair(a_string(#V), V)
#define JBD(A,V)  A.Bind(last_dot(#V), V)namespace atom
{//@generated "UML to C++ (com.ibm.xtools.transform.uml2.cpp.CPPTransformation)"class CJsonlizer : public IInterface{//Begin section for atom::CJsonlizer//TODO: Add attributes that you want preserved//End section for atom::CJsonlizerprivate://@generated "UML to C++ (com.ibm.xtools.transform.uml2.cpp.CPPTransformation)"CJsonExporter exporter;//@generated "UML to C++ (com.ibm.xtools.transform.uml2.cpp.CPPTransformation)"CJsonImporter importer;//@generated "UML to C++ (com.ibm.xtools.transform.uml2.cpp.CPPTransformation)"CJsonlizerRoot root;public://@generated "UML to C++ (com.ibm.xtools.transform.uml2.cpp.CPPTransformation)"CJsonlizer(); //@generated "UML to C++ (com.ibm.xtools.transform.uml2.cpp.CPPTransformation)"virtual ~CJsonlizer(); //@generated "UML to C++ (com.ibm.xtools.transform.uml2.cpp.CPPTransformation)"virtual IInterface * QueryInterface(U32 iid); //@generated "UML to C++ (com.ibm.xtools.transform.uml2.cpp.CPPTransformation)"bool Assign(CJson & data); //@generated "UML to C++ (com.ibm.xtools.transform.uml2.cpp.CPPTransformation)"bool Obtain(CJson & data); //@generated "UML to C++ (com.ibm.xtools.transform.uml2.cpp.CPPTransformation)"void Clear(); //@generated "UML to C++ (com.ibm.xtools.transform.uml2.cpp.CPPTransformation)"inline CJson GetCurrentNode(){//TODO Auto-generated method stubroot.GetCurrentNode();}//@generated "UML to C++ (com.ibm.xtools.transform.uml2.cpp.CPPTransformation)"inline void Push(CJson & node){//TODO Auto-generated method stubroot.Push( node );}//@generated "UML to C++ (com.ibm.xtools.transform.uml2.cpp.CPPTransformation)"inline void Pop(){//TODO Auto-generated method stubroot.Pop();}//@generated "UML to C++ (com.ibm.xtools.transform.uml2.cpp.CPPTransformation)"template<class T>inline CJsonlizer & operator <<(const T & value){//TODO Auto-generated method stubexporter.Bind( value );return( * this );}//@generated "UML to C++ (com.ibm.xtools.transform.uml2.cpp.CPPTransformation)"template<class T>inline CJsonlizer & operator <<(const pair<a_string, T> & value){//TODO Auto-generated method stubexporter.Bind( value.first.c_str(), value.second );return( * this );}//@generated "UML to C++ (com.ibm.xtools.transform.uml2.cpp.CPPTransformation)"template<class T>inline CJsonlizer & operator >>(T & value){//TODO Auto-generated method stubimporter.Bind( value );return( * this );}//@generated "UML to C++ (com.ibm.xtools.transform.uml2.cpp.CPPTransformation)"template<class T>inline CJsonlizer & operator >>(pair<a_string, T> & value){//TODO Auto-generated method stubimporter.Bind( value.first.c_str(), value.second );return( * this );}};  //end class CJsonlizer} //end namespace atom#endif

        最后就是最终的绑定接口了，接下来我展示一个简单的例子：

struct tagTest
{U32 index;a_string name;tagTest():index(0) {}~tagTest() {}
};struct tagTest2
{U32 index;tagTest value[4];tagTest2():index(0) {}~tagTest2() {}
};template<class A>
inline void Jsonlize(A & jr, tagTest & t, bool save)
{JBD( jr, t.index );JBD( jr, t.name );
}template<class A>
inline void Jsonlize(A & jr, tagTest2 & t, bool save)
{JBD( jr, t.index );JBD( jr, t.value );
}

准备了两个类，这两个类有聚合关系。然后我初始化这两个类，然后用Jsonizer将这个类导出成Json数据结构。

		tagTest2 in, out;in.index = 1;in.value[0].index = 101;in.value[0].name  = "101";in.value[1].index = 102;in.value[1].name  = "102";in.value[2].index = 103;in.value[2].name  = "103";in.value[3].index = 104;in.value[3].name  = "104";CJsonlizer jr;jr << in;CJson json;jr.Obtain( json );a_string value = json.Stringify();printf( "%s\n", value.c_str() );

运行的结果如下：

其实并不困难。大家也可以试试，其中 trait 的那些代码可以去看看boost的序列化相关的代码。