ClickHouse/contrib/libpoco/Foundation/include/Poco/Manifest.h

183 lines
3.3 KiB
C++

//
// Manifest.h
//
// $Id: //poco/1.4/Foundation/include/Poco/Manifest.h#1 $
//
// Library: Foundation
// Package: SharedLibrary
// Module: ClassLoader
//
// Definition of the Manifest class.
//
// Copyright (c) 2004-2006, Applied Informatics Software Engineering GmbH.
// and Contributors.
//
// SPDX-License-Identifier: BSL-1.0
//
#ifndef Foundation_Manifest_INCLUDED
#define Foundation_Manifest_INCLUDED
#include "Poco/Foundation.h"
#include "Poco/MetaObject.h"
#include <map>
#include <typeinfo>
namespace Poco {
class Foundation_API ManifestBase
/// ManifestBase is a common base class for
/// all instantiations of Manifest.
{
public:
ManifestBase();
virtual ~ManifestBase();
virtual const char* className() const = 0;
/// Returns the type name of the manifest's class.
};
template <class B>
class Manifest: public ManifestBase
/// A Manifest maintains a list of all classes
/// contained in a dynamically loadable class
/// library.
/// Internally, the information is held
/// in a map. An iterator is provided to
/// iterate over all the classes in a Manifest.
{
public:
typedef AbstractMetaObject<B> Meta;
typedef std::map<std::string, const Meta*> MetaMap;
class Iterator
/// The Manifest's very own iterator class.
{
public:
Iterator(const typename MetaMap::const_iterator& it)
{
_it = it;
}
Iterator(const Iterator& it)
{
_it = it._it;
}
~Iterator()
{
}
Iterator& operator = (const Iterator& it)
{
_it = it._it;
return *this;
}
inline bool operator == (const Iterator& it) const
{
return _it == it._it;
}
inline bool operator != (const Iterator& it) const
{
return _it != it._it;
}
Iterator& operator ++ () // prefix
{
++_it;
return *this;
}
Iterator operator ++ (int) // postfix
{
Iterator result(_it);
++_it;
return result;
}
inline const Meta* operator * () const
{
return _it->second;
}
inline const Meta* operator -> () const
{
return _it->second;
}
private:
typename MetaMap::const_iterator _it;
};
Manifest()
/// Creates an empty Manifest.
{
}
virtual ~Manifest()
/// Destroys the Manifest.
{
clear();
}
Iterator find(const std::string& className) const
/// Returns an iterator pointing to the MetaObject
/// for the given class. If the MetaObject cannot
/// be found, the iterator points to end().
{
return Iterator(_metaMap.find(className));
}
Iterator begin() const
{
return Iterator(_metaMap.begin());
}
Iterator end() const
{
return Iterator(_metaMap.end());
}
bool insert(const Meta* pMeta)
/// Inserts a MetaObject. Returns true if insertion
/// was successful, false if a class with the same
/// name already exists.
{
return _metaMap.insert(typename MetaMap::value_type(pMeta->name(), pMeta)).second;
}
void clear()
/// Removes all MetaObjects from the manifest.
{
for (typename MetaMap::iterator it = _metaMap.begin(); it != _metaMap.end(); ++it)
{
delete it->second;
}
_metaMap.clear();
}
int size() const
/// Returns the number of MetaObjects in the Manifest.
{
return int(_metaMap.size());
}
bool empty() const
/// Returns true iff the Manifest does not contain any MetaObjects.
{
return _metaMap.empty();
}
const char* className() const
{
return typeid(*this).name();
}
private:
MetaMap _metaMap;
};
} // namespace Poco
#endif // Foundation_Manifest_INCLUDED