text: /*=========================================================================
   *
   *  Copyright Insight Software Consortium
   *
   *  Licensed under the Apache License, Version 2.0 (the "License");
   *  you may not use this file except in compliance with the License.
   *  You may obtain a copy of the License at
   *
   *         http://www.apache.org/licenses/LICENSE-2.0.txt
   *
   *  Unless required by applicable law or agreed to in writing, software
   *  distributed under the License is distributed on an "AS IS" BASIS,
   *  WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
   *  See the License for the specific language governing permissions and
   *  limitations under the License.
   *
   *=========================================================================*/
  /*=========================================================================
   *
   *  Portions of this file are subject to the VTK Toolkit Version 3 copyright.
   *
   *  Copyright (c) Ken Martin, Will Schroeder, Bill Lorensen
   *
   *  For complete copyright, license and disclaimer of warranty information
   *  please refer to the NOTICE file at the top of the ITK source tree.
   *
   *=========================================================================*/
  #ifndef itkMetaDataObject_h
  #define itkMetaDataObject_h
  
  #include "itkMetaDataDictionary.h"
  #include "itkMacro.h"
  #include "itkArray.h"
  #include "itkMatrix.h"
  
  #include <cstring>
  
  namespace itk
  {
  /**
   * \class MetaDataObject
   * \brief Allows arbitrary data types to be stored as MetaDataObjectBase types,
   *        and to be stored in a MetaDataDictionary.
   *
   * \author Hans J. Johnson
   *
   * The MetaDataObject class is a templated class that
   * is a specialization of the MetaDataObjectBase type.
   * This class allows arbitrary data types to be
   * stored as MetaDataObjectBase types, and to be stored in
   * a MetaDataDictionary.
   *
   * Any class or built in type that has valid copy constructor and operator=
   * can be wrapped directly with this simple template type.
   *
   * Classes or built in types that do not have valid copy constructors or operator=
   * implemented will have to implement those functions by deriving from MetaDataObject<MetaDataObjectType>
   * and redefining the copy constructor and initializing constructor and the Get/Set functions
   * to work around those deficiencies.
   *
   * The behavior of the MetaDataObject<Type>::Print() function has many plausible
   * application dependent implementations.  The default implementation prints the
   * string "[UNKNOWN PRINT CHARACTERISTICS]" that works for all possible
   * MetaDataObject types.
   *
   * The application developer may overload the default implementation to provide
   * a specialized Print() characteristics to produce results desirable for their application.
   * A set of very crude Macros {NATIVE_TYPE_METADATAPRINT, ITK_OBJECT_TYPE_METADATAPRINT_1COMMA, ITK_IMAGE_TYPE_METADATAPRINT  }
   * are provided to facilitate a very simple implementation, and as an example.
   * \ingroup ITKCommon
   */
  template< typename MetaDataObjectType >
  class ITK_TEMPLATE_EXPORT MetaDataObject:public MetaDataObjectBase
  {
  public:
    ITK_DISALLOW_COPY_AND_ASSIGN(MetaDataObject);
  
    /** Smart pointer type alias support */
    using Self = MetaDataObject;
    using Superclass = MetaDataObjectBase;
    using Pointer = SmartPointer< Self >;
    using ConstPointer = SmartPointer< const Self >;
  
    /** Method for creation through the object factory. */
    itkFactorylessNewMacro(Self);
  
    /** Run-time type information (and related methods). */
    itkTypeMacro(MetaDataObject, MetaDataObjectBase);
  
    /**
     * The definition of this function is necessary to fulfill
     * the interface of the MetaDataObjectBase
     * \author Hans J. Johnson
     * \return A pointer to a const char array containing the unique type name.
     */
    const char * GetMetaDataObjectTypeName() const override;
  
    /**
     * The definition of this function is necessary to fulfill
     * the interface of the MetaDataObjectBase
     * \author Hans J. Johnson
     * \return A constant reference to a std::type_info object
     */
    const std::type_info & GetMetaDataObjectTypeInfo() const override;
  
    /**
     * Function to return the stored value of type MetaDataObjectType.
     * \author Hans J. Johnson
     * \return a constant reference to a MetaDataObjectType
     */
    const MetaDataObjectType & GetMetaDataObjectValue() const;
  
    /**
     * Function to set the stored value of type MetaDataObjectType.
     * \author Hans J. Johnson
     * \param newValue A constant reference to at MetaDataObjectType.
     */
    void SetMetaDataObjectValue(const MetaDataObjectType & newValue);
  
    /**
     * Defines the default behavior for printing out this element
     * \param os An output stream
     */
    void Print(std::ostream & os) const override;
  
  protected:
    MetaDataObject() = default;
    ~MetaDataObject() override = default;
  
  private:
    /**
     * A variable to store this derived type.
     * \author Hans J. Johnson
     */
    MetaDataObjectType m_MetaDataObjectValue;
  };
  
  /**
   * EncapsulateMetaData is a convenience function that encapsulates raw MetaData into a
   * MetaDataObject that can be put into the MetaDataDictionary.
   * \param Dictionary TODO
   * \param key TODO
   * \param invalue the value of type T that is to be encapsulated.
   * \return A smartpointer ot a MetaDataObject that is suitable for
   * insertion into a MetaDataDictionary.
   */
  template< typename T >
  inline void EncapsulateMetaData(MetaDataDictionary & Dictionary, const std::string & key, const T & invalue)
  {
    typename MetaDataObject< T >::Pointer temp = MetaDataObject< T >::New();
    temp->SetMetaDataObjectValue(invalue);
    Dictionary[key] = temp;
  }
  
  template< typename T >
  inline void EncapsulateMetaData(MetaDataDictionary & Dictionary, const char *key, const T & invalue)
  {
    EncapsulateMetaData(Dictionary, std::string(key), invalue);
  }
  
  /**
   * ExposeMetaData provides a shortcut for pulling a value of type
   * T out of a MetaDataDictionary.
   * If Dictionary[key] isn't set, return false, otherwise copy into
   * outval reference and return true.
   * \param Dictionary -- reference to a dictionary
   * \param key -- string identifier for this object
   * \param outval -- where to store value found in table.
   */
  template< typename T >
  inline bool ExposeMetaData(const MetaDataDictionary & Dictionary, const std::string key, T & outval)
  {
    auto keyIter = Dictionary.Find(key);
    if ( keyIter == Dictionary.End() )
      {
      return false;
      }
  
    auto const * const TempMetaDataObject = dynamic_cast< MetaDataObject< T > const * >( keyIter->second.GetPointer() );
    if ( TempMetaDataObject == nullptr )
      {
      return false;
      }
  
    outval = TempMetaDataObject->GetMetaDataObjectValue();
    return true;
  }
  
  } // end namespace itk
  
  /**
   * \def ITK_NATIVE_TYPE_METADATAPRINT( TYPE_NAME )
   * \brief An ugly macro to facilitate creating a simple implementation of
   * the MetaDataObject<Type>::Print() function for types that
   * have operator<< defined.
   * \param TYPE_NAME the native type parameter type
   */
  #define ITK_NATIVE_TYPE_METADATAPRINT(TYPE_NAME)        \
    template< >                                       \
    void                                              \
    ::itk::MetaDataObject< TYPE_NAME >                  \
    ::Print(std::ostream & os) const                  \
      {                                               \
      os << this->m_MetaDataObjectValue << std::endl; \
      }                                               \
  
  /**
   * \def ITK_OBJECT_TYPE_METADATAPRINT_1COMMA( TYPE_NAME_PART1, TYPE_NAME_PART2 )
   * \brief An ugly macro to facilitate creating a simple implementation of
   * the MetaDataObject< Type >::Print() function for
   * itk::Objects that have 1 comma in their type definition
   * \param TYPE_NAME_PART1
   * \param TYPE_NAME_PART2
   */
  #define ITK_OBJECT_TYPE_METADATAPRINT_1COMMA(TYPE_NAME_PART1, TYPE_NAME_PART2) \
    template< >                                                                  \
    void                                                                         \
    itk::MetaDataObject< TYPE_NAME_PART1, TYPE_NAME_PART2 >                      \
    ::Print(std::ostream & os) const                                             \
      {                                                                          \
      this->m_MetaDataObjectValue->Print(os);                                    \
      }                                                                          \
  
  /**
   * \def ITK_IMAGE_TYPE_METADATAPRINT( STORAGE_TYPE )
   * An ugly macro to facilitate creating a simple implementation of
   * the MetaDataObject<Type>::Print() function for
   * itk::Image\<STORAGE_TYPE,[1-8]\>\::Pointer
   * \param STORAGE_TYPE The storage type of the image type to print.
   */
  #define ITK_IMAGE_TYPE_METADATAPRINT(STORAGE_TYPE)                             \
    ITK_OBJECT_TYPE_METADATAPRINT_1COMMA(itk::Image< STORAGE_TYPE, 1 >::Pointer) \
    ITK_OBJECT_TYPE_METADATAPRINT_1COMMA(itk::Image< STORAGE_TYPE, 2 >::Pointer) \
    ITK_OBJECT_TYPE_METADATAPRINT_1COMMA(itk::Image< STORAGE_TYPE, 3 >::Pointer) \
    ITK_OBJECT_TYPE_METADATAPRINT_1COMMA(itk::Image< STORAGE_TYPE, 4 >::Pointer) \
    ITK_OBJECT_TYPE_METADATAPRINT_1COMMA(itk::Image< STORAGE_TYPE, 5 >::Pointer) \
    ITK_OBJECT_TYPE_METADATAPRINT_1COMMA(itk::Image< STORAGE_TYPE, 6 >::Pointer) \
    ITK_OBJECT_TYPE_METADATAPRINT_1COMMA(itk::Image< STORAGE_TYPE, 7 >::Pointer) \
    ITK_OBJECT_TYPE_METADATAPRINT_1COMMA(itk::Image< STORAGE_TYPE, 8 >::Pointer) \
  
  #ifndef ITK_MANUAL_INSTANTIATION
  #include "itkMetaDataObject.hxx"
  #endif
  
  #endif //itkMetaDataObject_h
  
  /** Explicit instantiations */
  #ifndef ITK_TEMPLATE_EXPLICIT_MetaDataObject
  // Explicit instantiation is required to ensure correct dynamic_cast
  // behavior across shared libraries.
  //
  // IMPORTANT: Since within the same compilation unit,
  //            ITK_TEMPLATE_EXPLICIT_<classname> defined and undefined states
  //            need to be considered. This code *MUST* be *OUTSIDE* the header
  //            guards.
  //
  #  if defined( ITKCommon_EXPORTS )
  //   We are building this library
  #    define ITKCommon_EXPORT_EXPLICIT ITK_TEMPLATE_EXPORT
  #  else
  //   We are using this library
  #    define ITKCommon_EXPORT_EXPLICIT ITKCommon_EXPORT
  #  endif
  namespace itk
  {
  
  ITK_GCC_PRAGMA_DIAG_PUSH()
  ITK_GCC_PRAGMA_DIAG(ignored "-Wattributes")
  
  extern template class ITKCommon_EXPORT_EXPLICIT MetaDataObject< bool >;
  extern template class ITKCommon_EXPORT_EXPLICIT MetaDataObject< unsigned char >;
  extern template class ITKCommon_EXPORT_EXPLICIT MetaDataObject< char >;
  extern template class ITKCommon_EXPORT_EXPLICIT MetaDataObject< signed char >;
  extern template class ITKCommon_EXPORT_EXPLICIT MetaDataObject< unsigned short >;
  extern template class ITKCommon_EXPORT_EXPLICIT MetaDataObject< short >;
  extern template class ITKCommon_EXPORT_EXPLICIT MetaDataObject< unsigned int >;
  extern template class ITKCommon_EXPORT_EXPLICIT MetaDataObject< int >;
  extern template class ITKCommon_EXPORT_EXPLICIT MetaDataObject< unsigned long >;
  extern template class ITKCommon_EXPORT_EXPLICIT MetaDataObject< long >;
  extern template class ITKCommon_EXPORT_EXPLICIT MetaDataObject< unsigned long long >;
  extern template class ITKCommon_EXPORT_EXPLICIT MetaDataObject< long long >;
  extern template class ITKCommon_EXPORT_EXPLICIT MetaDataObject< float >;
  extern template class ITKCommon_EXPORT_EXPLICIT MetaDataObject< double >;
  extern template class ITKCommon_EXPORT_EXPLICIT MetaDataObject< std::string >;
  extern template class ITKCommon_EXPORT_EXPLICIT MetaDataObject< std::vector<float> >;
  extern template class ITKCommon_EXPORT_EXPLICIT MetaDataObject< std::vector<double> >;
  extern template class ITKCommon_EXPORT_EXPLICIT MetaDataObject< std::vector<std::vector<float> > >;
  extern template class ITKCommon_EXPORT_EXPLICIT MetaDataObject< std::vector<std::vector<double> > >;
  extern template class ITKCommon_EXPORT_EXPLICIT MetaDataObject< Array<char> >;
  extern template class ITKCommon_EXPORT_EXPLICIT MetaDataObject< Array<int> >;
  extern template class ITKCommon_EXPORT_EXPLICIT MetaDataObject< Array<float> >;
  extern template class ITKCommon_EXPORT_EXPLICIT MetaDataObject< Array<double> >;
  extern template class ITKCommon_EXPORT_EXPLICIT MetaDataObject< Matrix<double> >;
  
  ITK_GCC_PRAGMA_DIAG_POP()
  
  } // end namespace itk
  #  undef ITKCommon_EXPORT_EXPLICIT
  #endif
  