epoc32/include/caf/virtualpathptr.h
branchSymbian2
changeset 2 2fe1408b6811
child 4 837f303aceeb
     1.1 --- /dev/null	Thu Jan 01 00:00:00 1970 +0000
     1.2 +++ b/epoc32/include/caf/virtualpathptr.h	Tue Mar 16 16:12:26 2010 +0000
     1.3 @@ -0,0 +1,139 @@
     1.4 +/*
     1.5 +* Copyright (c) 2003-2006 Nokia Corporation and/or its subsidiary(-ies).
     1.6 +* All rights reserved.
     1.7 +* This component and the accompanying materials are made available
     1.8 +* under the terms of the License "Eclipse Public License v1.0"
     1.9 +* which accompanies this distribution, and is available
    1.10 +* at the URL "http://www.eclipse.org/legal/epl-v10.html".
    1.11 +*
    1.12 +* Initial Contributors:
    1.13 +* Nokia Corporation - initial contribution.
    1.14 +*
    1.15 +* Contributors:
    1.16 +*
    1.17 +* Description: 
    1.18 +*
    1.19 +*/
    1.20 +
    1.21 +
    1.22 +
    1.23 +/** 
    1.24 +@file
    1.25 +
    1.26 +@publishedPartner
    1.27 +@released
    1.28 +*/
    1.29 +
    1.30 +
    1.31 +#ifndef __CAFVIRTUALPATHPTR_H__
    1.32 +#define __CAFVIRTUALPATHPTR_H__
    1.33 +
    1.34 +#include <e32base.h>
    1.35 +
    1.36 +namespace ContentAccess
    1.37 +	{
    1.38 +	class CVirtualPath;
    1.39 +
    1.40 +	/** 
    1.41 +	The character used to separate the URI from the UniqueId 
    1.42 +	when the two are concatenated into a single descriptor 
    1.43 +	*/
    1.44 +	_LIT(KCafVirtualPathSeparator, "|");
    1.45 +
    1.46 +	/**	Identifies the location of a file and a particular content object inside it.
    1.47 +
    1.48 +	TVirtualPathPtr points to the two descriptors (the URI and UniqueId) used 
    1.49 +	to initialise it. These descriptors must not be modified or destroyed while 
    1.50 +	the TVirtualPathPtr object is in use. 
    1.51 +	
    1.52 +	The URI must be in the format specified in RFC2396, found at http://www.ietf.org/.
    1.53 +
    1.54 +	The UniqueId will be created by the Agent. Content is only ever
    1.55 +	accessed by one agent so it is the agents responsibility to ensure the 
    1.56 +	UniqueId is truly unique within the file.
    1.57 +
    1.58 +	It is also possible to flatten a virtual path into a single descriptor. The
    1.59 +	ContentAccess::CVirtualPath class concatenates the URI, a separator, the KCafVirtualPathSeparator
    1.60 +	character, and the UniqueId to form a single URI. TVirtualPathPtr can be used to 
    1.61 +	decode this virtual path into the URI and the content object UniqueId. The 
    1.62 +	concatenated URI and UniqueId take the format:
    1.63 +	@code
    1.64 +		<URI><KCafVirtualPathSeparator><UniqueID>
    1.65 +	@endcode
    1.66 +	
    1.67 +	An example of this format is shown below:		
    1.68 +	@code
    1.69 +	// Create a CVirtualPath object to point to OBJECT1 inside file.dcf
    1.70 +	CVirtualPath *path = CVirtualPath::NewL(_L("C:\\directory\file.dcf"), _L("OBJECT1"));
    1.71 +
    1.72 +	// convert the URI and unique ID into a single URI.
    1.73 +	TVirtualPathPtr aPath = path->GetCombinedUriUniqueId();
    1.74 +	@endcode
    1.75 +	@note
    1.76 +	If a URI is supplied which contains multiple KCafVirtualPathSeparator characters 
    1.77 +	the rightmost KCafVirtualPathSeparator character will be taken as marking the end
    1.78 +	of the URI and the start of the UniqueId. When multiple KCafVirtualPathSeparator
    1.79 +	characters are present, under certain situations this will result in an invalid 
    1.80 +	URI and UniqueId being created for the virtual path and can lead to an undefined failure.
    1.81 +
    1.82 +	@publishedPartner
    1.83 +	@released
    1.84 +	*/
    1.85 +	class TVirtualPathPtr
    1.86 +		{
    1.87 +	public:
    1.88 +		/** Constructor used when the URI and UniqueId fields are separate 
    1.89 +		@param aUri The location of the file
    1.90 +		@param aUniqueId The location of the content within the file
    1.91 +		*/
    1.92 +		IMPORT_C TVirtualPathPtr(const TDesC& aUri, const TDesC& aUniqueId);
    1.93 +
    1.94 +		/** Constructor used for a concatenated URI and UniqueId.
    1.95 +		
    1.96 +		Note that the descriptor here may be just a URI or it could be a URI
    1.97 +		concatenated with the file's UniqueId. If it is a concatenated URI and 
    1.98 +		UniqueId the URI and UniqueId will be seperated by the KCafVirtualPathSeparator character.
    1.99 +		For more information see above.
   1.100 +		@param aCombinedUriUniqueId The location of the content object
   1.101 +		*/
   1.102 +		IMPORT_C TVirtualPathPtr(const TDesC& aCombinedUriUniqueId);
   1.103 +
   1.104 +		/** Copy constructor */
   1.105 +		IMPORT_C TVirtualPathPtr(const TVirtualPathPtr& aPtr);
   1.106 +
   1.107 +		/** The location of the file containing the content object 
   1.108 +		@return The location of the file
   1.109 +		*/
   1.110 +		IMPORT_C const TDesC& URI() const;
   1.111 +
   1.112 +		/** UniqueId supplied by a CAF Agent to identify the object within the 
   1.113 +		file.  
   1.114 +		@return The location of the content within the file
   1.115 +		*/
   1.116 +		IMPORT_C const TDesC& UniqueId() const;
   1.117 +
   1.118 +		/** Assignment operator */
   1.119 +		IMPORT_C TVirtualPathPtr& operator = (const TVirtualPathPtr& aVirtualPath);
   1.120 +	
   1.121 +		/** Assignment operator converts a single descriptor to a TVirtualPathPtr.
   1.122 +		If the descriptor is just a URI, the TVirtualPathPtr will point to the KDefaultContentObject within that file.
   1.123 +		If it is a concatenated URI and UniqueId the URI and UniqueId will be seperated by the KCafVirtualPathSeparator. 
   1.124 +		character as detailed in the description above.   
   1.125 +		*/
   1.126 +		IMPORT_C TVirtualPathPtr& operator = (const TDesC& aCombinedUriUniqueId);
   1.127 +
   1.128 +
   1.129 +	private:
   1.130 +		// The Set() function is only used by CVirtualPath
   1.131 +		friend class CVirtualPath;
   1.132 +
   1.133 +		/** Used to redirect the TVirtualPathPtr to point at a different set of descriptors */
   1.134 +		void Set(const TDesC& aUri, const TDesC& aUniqueId);
   1.135 +
   1.136 +	private:
   1.137 +		TPtrC iUri;
   1.138 +		TPtrC iUniqueId;
   1.139 +		};
   1.140 +	}
   1.141 +
   1.142 +#endif