File indexing completed on 2024-05-19 03:51:49

 /*
     SPDX-FileCopyrightText: 2007, 2008 Nikolas Zimmermann <zimmermann@kde.org>
 
     SPDX-License-Identifier: LGPL-2.0-or-later
 */
 
 #ifndef MARBLE_GEOTAGHANDLER_H
 #define MARBLE_GEOTAGHANDLER_H
 
 #include <QHash>
 #include "marble_export.h"
 #include "GeoParser.h"
 
 namespace Marble
 {
 
 class GeoNode;
 
 /**
  * @brief A base class for XML tag handlers
  * This is a base class that is used in the GeoParser architecture. To implement
  * a new GeoData format you will need to subclass GeoTagHandler and reimplement
  * the @see parse(GeoParser&) method. You also need to register the newly
  * implemented GeoTagHandler by declaring an instance of the helper structure
  * @see GeoTagHandlerRegistrar with a corresponding @see QualifiedName.
  */
 class MARBLE_EXPORT GeoTagHandler
 {
 public:
     // API to be implemented by child handlers.
     virtual GeoNode* parse(GeoParser&) const = 0;
 
 protected: // This base class is not directly constructable nor is it copyable.
     GeoTagHandler();
     virtual ~GeoTagHandler();
 
 private:
     GeoTagHandler(const GeoTagHandler&) = delete;
     GeoTagHandler& operator=(const GeoTagHandler&) = delete;
 
 private: // Only our registrar is allowed to register tag handlers.
     friend struct GeoTagHandlerRegistrar;
     static void registerHandler(const GeoParser::QualifiedName&, const GeoTagHandler*);
     static void unregisterHandler(const GeoParser::QualifiedName&);
 
 private: // Only our parser is allowed to access tag handlers.
     friend class GeoParser;
     static const GeoTagHandler* recognizes(const GeoParser::QualifiedName&);
 
 private:
     typedef QHash<GeoParser::QualifiedName, const GeoTagHandler*> TagHash;
 
     static TagHash* tagHandlerHash();
     static TagHash* s_tagHandlerHash;
 };
 
 // Helper structure
 struct GeoTagHandlerRegistrar
 {
 public:
     GeoTagHandlerRegistrar(const GeoParser::QualifiedName& name, const GeoTagHandler* handler)
         :m_name( name )
     {
         GeoTagHandler::registerHandler(name, handler);
     }
 
     ~GeoTagHandlerRegistrar()
     {
         GeoTagHandler::unregisterHandler(m_name);
     }
 
 private:
     GeoParser::QualifiedName m_name;
 };
 
 // Macros to ease registering new handlers
 #define GEODATA_DEFINE_TAG_HANDLER(Module, UpperCaseModule, Name, NameSpace) \
     static GeoTagHandlerRegistrar s_handler##Name##NameSpace(GeoParser::QualifiedName(QLatin1String(Module##Tag_##Name), QLatin1String(NameSpace)), \
                                                              new UpperCaseModule##Name##TagHandler());
 
 }
 
 #endif