cbs/CbsServer/ServerInc/CCbsDbImpTopicCollection.h
changeset 0 ff3b6d0fd310
--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/cbs/CbsServer/ServerInc/CCbsDbImpTopicCollection.h	Tue Feb 02 01:11:09 2010 +0200
@@ -0,0 +1,205 @@
+/*
+* Copyright (c) 2003 Nokia Corporation and/or its subsidiary(-ies). 
+* All rights reserved.
+* This component and the accompanying materials are made available
+* under the terms of "Eclipse Public License v1.0"
+* which accompanies this distribution, and is available
+* at the URL "http://www.eclipse.org/legal/epl-v10.html".
+*
+* Initial Contributors:
+* Nokia Corporation - initial contribution.
+*
+* Contributors:
+*
+* Description:  This file contains the header file of the CCbsDbImpTopicCollection class.
+*    
+*                This class represents the topic collection stored in the database.
+*                Topic collection keeps a record of topic identities received from
+*                the network. Topic identity includes a topic name and a topic number. 
+*                These can be accessed but not modified.
+*
+*/
+
+
+#ifndef     CCBSDBIMPTOPICCOLLECTION_H   
+#define     CCBSDBIMPTOPICCOLLECTION_H   
+
+//  INCLUDES
+
+#include <e32base.h>
+#include <e32std.h>
+#include <s32stor.h>
+#include <f32file.h>
+#include <s32file.h>
+
+#include "MCbsDbTopicCollectionObserver.H"
+
+//  CLASS DECLARATION 
+
+class CCbsDbImp;
+
+/**
+*   This class defines the interface for handling topic collections.
+*
+*   User's Guide for accessing stored topic identities:
+*   GetTopicIdentityCount(TInt&)
+*       Retrieves the number of topic identities currently stored in the 
+*       topic collection.
+*   GetTopicIdentityL(TInt&, TCbsDbTopicIdentity&)
+*       Retrieves a single topic identity identified with an index.
+*
+*   User's Guide for observing the topic collection.
+*   AddObserverL(MCbsDbTopicCollectionObserver*)
+*       Registers an observer which is notified of changes in the topic
+*       collection.
+*   RemoveObserverL(MCbsDbTopicCollectionObserver*)
+*       Unregisters an observer.
+*
+*   User's Guide for modifying the topic collection:
+*   Clear()
+*       Clears the current topic collection. This is called by the index
+*       message parsing routine when it's about to parse a root index
+*       message. Topic identities contained in subsequent child subindex 
+*       messages, if any, are then simply added with AddTopicIdentityL()
+*   AddTopicIdentityL(TCbsDbTopicIdentity&)
+*       Adds a topic identity into the topic collection's buffer.
+*   Apply()
+*       Writes the topic identity buffer into persistent storage.
+*       Clears the buffer.
+*   
+*/
+class CCbsDbImpTopicCollection : public CBase
+    {
+
+    public:     // New functions.
+        /**
+        *   Creates a new instance of the class.
+        *       
+        *   @return                     A pointer to the created 
+        *                               CCbsDbImpTopicCollection instance.
+        */
+        static CCbsDbImpTopicCollection* NewL();
+
+        /**
+        *   Destructor. 
+        */
+        ~CCbsDbImpTopicCollection();
+
+    public: 
+        /**
+        *   Returns the total amount of topic identities 
+        *   the collection contans.
+        *
+        *   @param aCount               The method stores the topic identity
+        *                               count to this variable.
+        */
+        void GetTopicIdentityCount( TInt& aCount ) const;
+
+        /**
+        *   Stores a topic identity (index is aIndex in the list) to aIdentity.
+        *   The method leaves if the parameter aIndex is invalid.
+        *
+        *   Exceptions:
+        *   KErrNotFound                The requested topic identity was not 
+        *                               found.
+        *
+        *   @param aIndex               Used to index identities.
+        *   @param aIdentity            The method stores a topic identity to 
+        *                               the parameter.
+        */
+        void GetTopicIdentityL( 
+            TInt& aIndex, 
+            TCbsDbTopicIdentity& aIdentity ) const;
+
+        /**
+        *   Adds a topic collection observer. 
+        *
+        *   Panics if aObserver is null.
+        *
+        *   Exceptions:
+        *   KErrNoMemory                OOM
+        *
+        *   @param aObserver            Pointer to the new observer to be added
+        */
+        void AddObserverL( MCbsDbTopicCollectionObserver* aObserver );
+
+        /**
+        *   Removes a topic collection observer. 
+        *
+        *   Panics if aObserver is null or aObserver is not registered
+        *   as an observer.
+        *
+        *   @param aObserver            Pointer to the observer to be removed
+        */
+        void RemoveObserver( const MCbsDbTopicCollectionObserver* aObserver );
+
+        /**
+        *   Clears the topic collection builder's buffered topic list.
+        *   This does not have any effect on identities stored in 
+        *   the database.
+        *
+        *   This method should be called prior to parsing a root index
+        *   message. Any topic identities extracted from subindex messages
+        *   should be appended into collection with AddTopicIdentityL()
+        *   without any call to Clear().
+        */
+        void Clear();
+
+        /**
+        *   Stores topic identities which were added to the topic 
+        *   collection with AddTopicIdentityL() after previous call to 
+        *   Apply().
+        *
+        */
+        void Apply();
+
+        /**
+        *   Adds a new topic identity to the buffered collection.
+        *   A topic identity contains topic name and number. If the
+        *   topic exists already, nothing is done.
+        *   
+        *   This method will return KErrAlreadyExists, if there is already 
+        *   another topic identity that has the same number.
+        *
+        *   Exceptions:
+        *   KErrNoMemory                OOM
+        *   KErrArgument                Topic number of the given identity is
+        *                               out of valid range.
+        *
+        *   @param  aIdentity           Topic identity to be added.
+        */
+        void AddTopicIdentityL( const TCbsDbTopicIdentity& aIdentity );
+
+    private:
+
+        /**
+        *   Constructor. 
+        *
+        */
+        CCbsDbImpTopicCollection();
+
+        /**
+        *   Finalizes the construction.
+        *
+        */
+        void ConstructL();
+
+        /**
+        *   Notifies topic collection observers about changed topic 
+        *   collection.
+        */       
+        void NotifyObservers();
+
+    private:
+
+        // Own: Contains the observers.
+        CArrayFixFlat< MCbsDbTopicCollectionObserver* >* iObservers;
+
+        // Own: Contains buffered topic identities.
+        CArrayFix< TCbsDbTopicIdentity >* iIdentities;
+
+    };
+
+#endif      //  CCBSDBIMPTOPICCOLLECTION_H   
+            
+// End of File