AOO410/main/connectivity/inc/connectivity/dbcharset.hxx

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#ifndef _DBHELPER_DBCHARSET_HXX_
#define _DBHELPER_DBCHARSET_HXX_

#include <comphelper/stl_types.hxx>
#include <rtl/textenc.h>
#include <rtl/tencinfo.h>
#include <rtl/ustring.hxx>
#include "connectivity/dbtoolsdllapi.hxx"

//.........................................................................
namespace dbtools
{
//.........................................................................

	//=========================================================================
	//= OCharsetMap
	//=========================================================================
	/** is a class which translates between different charset representations.

		<p>The set of recognized charsets is very limited: only the ones which are database relevant are
		implemented at the moment</p>

		<p>Possible representations are:
		<ul>
			<li><b>IANA names.</b>
			Have a look at <A href="http://www.iana.org/assignments/character-sets">this document</A> for
			more details</li>
			<li><b>rtl_TextEncoding</b></li>
		</ul>
		</p>
	*/
	class OOO_DLLPUBLIC_DBTOOLS OCharsetMap
	{
	protected:
		DECLARE_STL_STDKEY_SET( rtl_TextEncoding, TextEncBag );

		TextEncBag	m_aEncodings;

	public:
		class CharsetIterator;
		friend class OCharsetMap::CharsetIterator;
		typedef CharsetIterator iterator;
		typedef CharsetIterator const_iterator;

		OCharsetMap();
		virtual ~OCharsetMap();

		struct IANA { };

		/** find the given text encoding in the map.
			@return the <em>end</em> iterator if the encoding could not be found.
		*/
		CharsetIterator	find(const rtl_TextEncoding _eEncoding) const;
		/** find the given IANA name in the map.
			@return the <em>end</em> iterator if the IANA name could not be found.
		*/
		CharsetIterator	find(const ::rtl::OUString& _rIanaName, const IANA&) const;

		sal_Int32	size() const { ensureConstructed( ); return m_aEncodings.size(); }

		/// get access to the first element of the charset collection
		CharsetIterator	begin() const;
		/// get access to the (last + 1st) element of the charset collection
		CharsetIterator	end() const;

	protected:
		// needed because we want to call a virtual method during construction
				void lateConstruct();
		inline	void ensureConstructed( ) const { if ( m_aEncodings.empty() ) const_cast< OCharsetMap* >( this )->lateConstruct(); }

		virtual	sal_Bool approveEncoding( const rtl_TextEncoding _eEncoding, const rtl_TextEncodingInfo& _rInfo ) const;
	};

	//-------------------------------------------------------------------------
	//- CharsetIteratorDerefHelper
	//-------------------------------------------------------------------------
	class OOO_DLLPUBLIC_DBTOOLS CharsetIteratorDerefHelper
	{
		friend class OCharsetMap::CharsetIterator;

		rtl_TextEncoding	m_eEncoding;
		::rtl::OUString		m_aIanaName;

	public:
		CharsetIteratorDerefHelper(const CharsetIteratorDerefHelper& _rSource);

		rtl_TextEncoding	getEncoding() const	{ return m_eEncoding; }
		::rtl::OUString		getIanaName() const	{ return m_aIanaName; }

	protected:
		CharsetIteratorDerefHelper();
		CharsetIteratorDerefHelper( const rtl_TextEncoding _eEncoding, const ::rtl::OUString& _rIanaName );

	};


	//-------------------------------------------------------------------------
	//- OCharsetMap::CharsetIterator
	//-------------------------------------------------------------------------
	class OOO_DLLPUBLIC_DBTOOLS OCharsetMap::CharsetIterator
	{
		friend class OCharsetMap;

		friend OOO_DLLPUBLIC_DBTOOLS bool operator==(const CharsetIterator& lhs, const CharsetIterator& rhs);
		friend bool operator!=(const CharsetIterator& lhs, const CharsetIterator& rhs) { return !(lhs == rhs); }

//		friend sal_Int32 operator-(const CharsetIterator& lhs, const CharsetIterator& rhs);

	protected:
		const OCharsetMap*						m_pContainer;
		OCharsetMap::TextEncBag::const_iterator	m_aPos;

	public:
		CharsetIterator(const CharsetIterator& _rSource);
		~CharsetIterator();

		CharsetIteratorDerefHelper operator*() const;
		// no -> operator
		// this would require us to a) store CharsetIteratorDerefHelper instances ourself so that we
		// can return a pointer or b) introduce a -> operator on the CharsetIteratorDerefHelper, too.

		/// prefix increment
		const CharsetIterator&	operator++();
		/// postfix increment
		const CharsetIterator	operator++(int) { CharsetIterator hold(*this); ++*this; return hold; }

		/// prefix decrement
		const CharsetIterator&	operator--();
		/// postfix decrement
		const CharsetIterator	operator--(int) { CharsetIterator hold(*this); --*this; return hold; }

	protected:
		CharsetIterator(const OCharsetMap* _pContainer, OCharsetMap::TextEncBag::const_iterator _aPos );
	};

//.........................................................................
}	// namespace dbtools
//.........................................................................

#endif // _DBHELPER_DBCHARSET_HXX_