--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/emailservices/emailstore/base_plugin/inc/nestedao.h	Mon May 03 12:23:15 2010 +0300
@@ -0,0 +1,85 @@
+/*
+* Copyright (c) 2010 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:  Class used to implement nested active object used to handle 
+* deletion of large number of messages by breaking them into smaller chunks
+*
+*/
+
+#ifndef __NESTED_AO_H__
+#define __NESTED_AO_H__
+
+//  Include Files
+
+
+#include <e32base.h>
+
+
+class MDeletionHandler
+    {
+public:
+    enum TState
+        {
+        EInProgress,
+        EFree
+        };
+    //Deletes messages from aStartIndex KSizeOfChunk at a time
+    virtual TBool DeleteMessagesInChunksL( TInt aStartIndex ) = 0;
+    };
+//Time interval between issuing 2 requests to delete messages
+const TInt KWaitIntervalInMicroSecs=500;
+//Maximum number of messages deleted in one go
+const TInt KSizeOfChunk=10;
+
+NONSHARABLE_CLASS ( CNestedAO ) : public CTimer
+    {
+    public:
+        
+        static CNestedAO* NewL( MDeletionHandler& aDeletionHandler );
+        virtual ~CNestedAO();
+        // --------------------------------------------------------------------------
+        // CNestedAO::DeleteMessagesAsync
+        // Used to delete messages asynchronously 
+        // Deleting a small number of messages at a time
+        // ------------
+        void DeleteMessagesAsync();
+        // --------------------------------------------------------------------------
+        // CNestedAO::Rc
+        // Used to return the iStatus return value
+        // ------------        
+        TInt Rc() { return iRc; }
+        
+    private:
+        CNestedAO( MDeletionHandler& aDeletionHandler );
+        void ConstructL();
+        
+        // inherited from CActive
+        virtual void RunL();
+        virtual void DoCancel();
+        // --------------------------------------------------------------------------
+        // CNestedAO::Stop
+        // Stops the scheduler from running
+        // Called after all messages are processed
+        // or in error condition
+        // ------------           
+        void Stop();
+        
+    private:
+        CActiveSchedulerWait* iNestedWait;
+        MDeletionHandler& iDeletionHandler;
+        TInt iDeletionIndex;
+        TInt iRc;
+    };
+
+
+#endif  //__NESTED_AO_H__