src/framework/XMLRecognizer.hpp

/*
 * The Apache Software License, Version 1.1
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 * This software consists of voluntary contributions made by many
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/**
 *  $Log$
 *  Revision 1.2  1999/11/23 01:49:27  rahulj
 *  Cannot use class qualifier in class defn. CC under HPUX is happy.
 *
 *  Revision 1.1.1.1  1999/11/09 01:08:37  twl
 *  Initial checkin
 *
 *  Revision 1.2  1999/11/08 20:44:40  rahul
 *  Swat for adding in Product name and CVS comment log variable.
 *
 */

#if !defined(XMLRECOGNIZER_HPP)
#define XMLRECOGNIZER_HPP

//
//  This class provides some simple code to recognize the encodings of
//  XML files. This recognition only does very basic sensing of the encoding
//  in a broad sense. Basically its just enough to let us get started and
//  read the XMLDecl line. The scanner, once it reads the XMLDecl, will
//  tell the reader any actual encoding string it found and the reader can
//  update itself to be more specific at that point.
//
class XMLPARSER_EXPORT XMLRecognizer
{
public :
    // -----------------------------------------------------------------------
    //  Class types
    //
    //  This enum represents the various encoding families that we have to
    //  deal with individually at the scanner level. This does not indicate
    //  the exact encoding, just the rough family that would let us scan
    //  the XML/TextDecl to find the encoding string.
    //
    //  The 'L's and 'B's stand for little or big endian. We conditionally
    //  create versions that will automatically map to the local UTF-16 and
    //  UCS-4 endian modes.
    //
    //  OtherEncoding means that its some transcoder based encoding, i.e. not
    //  one of the ones that we do internally. Its a special case and should
    //  never be used directly outside of the reader.
    //
    //  NOTE: Keep this in sync with the name map array in the Cpp file!!
    // -----------------------------------------------------------------------
    enum Encodings
    {
        EBCDIC          = 0
        , UCS_4B        = 1
        , UCS_4L        = 2
        , US_ASCII      = 3
        , UTF_8         = 4
        , UTF_16B       = 5
        , UTF_16L       = 6

        , Encodings_Count
        , Encodings_Min = EBCDIC
        , Encodings_Max = UTF_16L

        , OtherEncoding = 999

        #if defined(ENDIANMODE_BIG)
        , Def_UTF16     = UTF_16B
        , Def_UCS4      = UCS_4B
        #else
        , Def_UTF16     = UTF_16L
        , Def_UCS4      = UCS_4L
        #endif
    };


    // -----------------------------------------------------------------------
    //  Encoding recognition methods
    // -----------------------------------------------------------------------
    static Encodings basicEncodingProbe
    (
        const   XMLByte* const      rawBuffer
        , const unsigned int        rawByteCount
    );

    static Encodings encodingForName
    (
        const   XMLCh* const    theEncName
    );

    static const XMLCh* nameForEncoding(const Encodings theEncoding);


private :
    // -----------------------------------------------------------------------
    //  Unimplemented constructors, operators, and destructor
    //
    //  This class is effectively being used as a namespace for some static
    //  methods.
    // -----------------------------------------------------------------------
    XMLRecognizer();
    ~XMLRecognizer();
    void operator=(const XMLRecognizer&);
};

#endif