src/apps/cortex/Persistence/Wrappers/FlatMessageIO.h

   1 /*
   2  * Copyright (c) 1999-2000, Eric Moon.
   3  * All rights reserved.
   4  *
   5  * Redistribution and use in source and binary forms, with or without
   6  * modification, are permitted provided that the following conditions
   7  * are met:
   8  *
   9  * 1. Redistributions of source code must retain the above copyright
  10  *    notice, this list of conditions, and the following disclaimer.
  11  *
  12  * 2. Redistributions in binary form must reproduce the above copyright
  13  *    notice, this list of conditions, and the following disclaimer in the
  14  *    documentation and/or other materials provided with the distribution.
  15  *
  16  * 3. The name of the author may not be used to endorse or promote products
  17  *    derived from this software without specific prior written permission.
  18  *
  19  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR "AS IS" AND ANY EXPRESS OR
  20  * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
  21  * OF TITLE, NON-INFRINGEMENT, MERCHANTABILITY AND FITNESS FOR A PARTICULAR
  22  * PURPOSE ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY
  23  * DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES
  24  * (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
  25  * LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED
  26  * AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR
  27  * TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
  28  * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
  29  */
  30
  31
  32 // FlatMessageIO.h
  33 // * PURPOSE
  34 //   Efficient export/import of BMessages to and from
  35 //   XML using the Cortex persistence library.
  36 //   Messages are stored in flattened form.
  37 // * HISTORY
  38 //   e.moon             6jul99          Begun.
  39 //
  40 // Example:
  41 //
  42 // <flat-BMessage
  43 //   encoding = 'base64'>
  44 //   nKJNFBlkn3lknbxlkfnbLKN/lknlknlDSLKn3lkn3l2k35234ljk234
  45 //   lkdsg23823nlknsdlkbNDSLKBNlkn3lk23n4kl23n423lknLKENL+==
  46 // </flat-BMessage>
  47
  48 #ifndef __FlatMessageIO_H__
  49 #define __FlatMessageIO_H__
  50
  51 #include <Message.h>
  52 #include <String.h>
  53 #include "XML.h"
  54
  55 #include "cortex_defs.h"
  56 __BEGIN_CORTEX_NAMESPACE
  57
  58 class FlatMessageIO :
  59         public          IPersistent {
  60
  61 public:                                 // *** ctor/dtor/accessor
  62         virtual ~FlatMessageIO();
  63
  64         FlatMessageIO();
  65
  66         // When given a message to export, this object does NOT take
  67         // responsibility for deleting it.  It will, however, handle
  68         // deletion of an imported BMessage.
  69
  70         FlatMessageIO(const BMessage* message);
  71         void setMessage(BMessage* message);
  72
  73         // Returns 0 if no message has been set, and if no message has
  74         // been imported.
  75
  76         const BMessage* message() const { return m_message; }
  77
  78         // Returns true if the message will be automatically deleted.
  79
  80         bool ownsMessage() const { return m_ownMessage; }
  81
  82 public:                                 // *** static setup method
  83         // call this method to install hooks for the tags needed by
  84         // FlatMessageIO into the given document type
  85         static void AddTo(XML::DocumentType* pDocType);
  86
  87 public:                                 // *** XML formatting
  88         static const char* const                        s_element;
  89         static const uint16                                     s_encodeToMax                   = 72;
  90         static const uint16                                     s_encodeToMin                   = 24;
  91
  92 public:                                 // *** IPersistent impl.
  93
  94 //      virtual void xmlExport(
  95 //              ostream&                                        stream,
  96 //              ExportContext&          context) const;
  97
  98         // EXPORT:
  99
 100         void xmlExportBegin(
 101                 ExportContext& context) const;
 102
 103         void xmlExportAttributes(
 104                 ExportContext& context) const;
 105
 106         void xmlExportContent(
 107                 ExportContext& context) const;
 108
 109         void xmlExportEnd(
 110                 ExportContext& context) const;
 111
 112
 113         // IMPORT:
 114
 115         virtual void xmlImportBegin(
 116                 ImportContext&          context);
 117
 118         virtual void xmlImportAttribute(
 119                 const char*                                     key,
 120                 const char*                                     value,
 121                 ImportContext&          context);
 122
 123         virtual void xmlImportContent(
 124                 const char*                                     data,
 125                 uint32                                          length,
 126                 ImportContext&          context);
 127
 128         virtual void xmlImportChild(
 129                 IPersistent*                    child,
 130                 ImportContext&          context);
 131
 132         virtual void xmlImportComplete(
 133                 ImportContext&          context);
 134
 135 private:                                        // *** members
 136         bool                                            m_ownMessage;
 137         BMessage*                       m_message;
 138
 139         // encoded data is cached here during the import process
 140         BString                         m_base64Data;
 141 };
 142
 143 __END_CORTEX_NAMESPACE
 144
 145 #endif /*__FlatMessageIO_H__*/