// C++ informative line for the emacs editor: -*- C++ -*-
/* * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * *
  * Copyright by the Board of Trustees of the University of Illinois.         *
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#ifndef _IdComponent_H
#define _IdComponent_H

// IdComponent provides a mechanism to handle
// reference counting for an identifier of any HDF5 object.

#ifndef H5_NO_NAMESPACE
namespace H5 {
#endif

class H5_DLLCPP IdComponent {
   public:
	// Parent classes must reset the current IdComponent copy
	// before setting new id to control reference count
	void setId( hid_t new_id );

	// Pure virtual function so appropriate close function can
	// be called by subclasses' for the corresponding object
	virtual void p_close() const = 0;

	// Creates an object to hold an HDF5 identifier
	IdComponent( const hid_t h5_id );

	// Copy constructor: makes copy of the original IdComponent object.
	IdComponent( const IdComponent& original );

	// Gets the value of IdComponent's data member
	virtual hid_t getId () const;

	// Increment reference counter
	void incRefCount();

	// Decrement reference counter
	void decRefCount();

	// Get the reference counter to this identifier
	int getCounter();

	// Decrements the reference counter then determines if there are no more
	// reference to this object
	bool noReference();

	// Assignment operator
	IdComponent& operator=( const IdComponent& rhs );

	void reset();
	void resetId();

	// Destructor
	virtual ~IdComponent();

   protected:
	hid_t id;	// HDF5 object id
	RefCounter* ref_count; // used to keep track of the
	                              // number of copies of an object

	// Default constructor
	IdComponent();

	// Creates a reference to an HDF5 object or a dataset region.
	void* p_reference(const char* name, hid_t space_id, H5R_type_t ref_type) const;
	
	// Retrieves the type of object that an object reference points to.
	H5G_obj_t p_get_obj_type(void *ref, H5R_type_t ref_type) const;

	// Retrieves a dataspace with the region pointed to selected.
	hid_t p_get_region(void *ref, H5R_type_t ref_type) const;

}; // end class IdComponent

#ifndef H5_NO_NAMESPACE
}
#endif
#endif