1 /*

     2 * Copyright (c) 2005-2009 Nokia Corporation and/or its subsidiary(-ies).

     3 * All rights reserved.

     4 * This component and the accompanying materials are made available

     5 * under the terms of "Eclipse Public License v1.0"

     6 * which accompanies this distribution, and is available

     7 * at the URL "http://www.eclipse.org/legal/epl-v10.html".

     8 *

     9 * Initial Contributors:

    10 * Nokia Corporation - initial contribution.

    11 *

    12 * Contributors:

    13 *

    14 * Description: 

    15 *

    16 */

    17 

    18 

    19 #ifndef __TXTWRITER_H__

    20 #define __TXTWRITER_H__

    21 

    22 #include <e32std.h>

    23 

    24 //////////////////////////////////////////////////////////////////////////////////////////////

    25 //////////////////////////////////////////////////////////////////////////////////////////////

    26 // MTextWriter interface

    27 

    28 /**

    29 MTextWriter class is an interface, implemented by TParagraphTextWriter and

    30 TLineTextWriter classes. It offers two functions:

    31 1) void WriteL(TText aChar) - to output a single character.

    32 2) void FlushL() - if the implementations have stored some of the incomming characters 

    33                    for further processing, they will be immediately flushed to the output.

    34 They are not supposed to be called directly. MTextWriter class, together with TSLBTransaltor,

    35 MOutputChar, TParagraphTextWriter and TLineTextWriter classes builds a framework, used for 

    36 correct filtering of the 0x0D and 0x0A characters and translating them to line breaks or spaces,

    37 depending of the text file organisation.

    38 @internalComponent

    39 */

    40 class MTextWriter

    41 	{

    42 public:

    43 	virtual void WriteL(TText aChar) = 0;

    44 	virtual void FlushL()

    45 		{

    46 		}

    47 	};

    48 

    49 //////////////////////////////////////////////////////////////////////////////////////////////

    50 //////////////////////////////////////////////////////////////////////////////////////////////

    51 // MOutputChar interface

    52 

    53 /**

    54 MOutputChar interface offers "void OutputCharL(TText aChar)" method, which gets as an input 

    55 character, which may be a line break or something else, but not 0x0D or 0x0A characters, which

    56 were filtered earlier.

    57 @internalComponent

    58 */

    59 class MOutputChar

    60 	{

    61 public:

    62 	virtual void OutputCharL(TText aChar) = 0;

    63 	};

    64 

    65 //////////////////////////////////////////////////////////////////////////////////////////////

    66 //////////////////////////////////////////////////////////////////////////////////////////////

    67 // TSLBTransaltor class

    68 

    69 /**

    70 TSLBTransaltor class offers functionality for processing a stream of characters, filtering

    71 0x0D and 0x0A characters or (0x0D 0x0A) combination, and transating them to single line breaks.  

    72 It sends translated characters for a further processing using MTextWriter::WriteL() call.

    73 The translation rules are:

    74  - 0x0D      - line break;

    75  - 0x0A      - line break;

    76  - 0x0D 0x0A - line break;

    77 @internalComponent

    78 */

    79 class TSLBTransaltor

    80 	{

    81 public:

    82 	inline TSLBTransaltor(MTextWriter& aTextWriter);

    83 	void ProcessL(TText aChar);

    84 	void FlushL();

    85 private:

    86 	MTextWriter&	iTextWriter;

    87 	TText			iPrevChar;

    88 	};

    89 

    90 //////////////////////////////////////////////////////////////////////////////////////////////

    91 //////////////////////////////////////////////////////////////////////////////////////////////

    92 // TParagraphTextWriter class

    93 

    94 /**

    95 TParagraphTextWriter class is a concrete implementation of MTextWriter interface.

    96 It is used to translate line breaks in the input sequence to paragraph delimiters.

    97 Every line break from the input is replaced with paragraph delimiter in the output.

    98 MOutputChar interface is used for the output.

    99 @internalComponent

   100 */

   101 NONSHARABLE_CLASS(TParagraphTextWriter) : public MTextWriter

   102 	{

   103 public:

   104 	inline TParagraphTextWriter(MOutputChar& aOutputChar);

   105 	virtual void WriteL(TText aChar);

   106 private:

   107 	MOutputChar&	iOutputChar;

   108 	};

   109 

   110 //////////////////////////////////////////////////////////////////////////////////////////////

   111 //////////////////////////////////////////////////////////////////////////////////////////////

   112 // TLineTextWriter class

   113 

   114 /**

   115 TLineTextWriter class is a concrete implementation of MTextWriter interface.

   116 It is used to translate line breaks in the input sequence to paragraph delimiters or spaces.

   117 The translation rules are:

   118  - single line break - space;

   119  - double line break - paragraph delimiter;

   120 MOutputChar interface is used for the output.

   121 @internalComponent

   122 */

   123 NONSHARABLE_CLASS(TLineTextWriter) : public MTextWriter

   124 	{

   125 public:

   126 	inline TLineTextWriter(MOutputChar& aOutputChar);

   127 	virtual void WriteL(TText aChar);

   128 	virtual void FlushL();

   129 private:

   130 	MOutputChar&	iOutputChar;

   131 	TText			iPrevChar;

   132 	};

   133 

   134 

   135 #include "TxtWriter.inl"

   136 

   137 #endif //__TXTWRITER_H__