diff -r 14dc2103a631 -r ed1c9f64298a trace/tracebuilder/com.nokia.tracebuilder/src/com/nokia/tracebuilder/engine/TraceBuilderEngine.java
--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/trace/tracebuilder/com.nokia.tracebuilder/src/com/nokia/tracebuilder/engine/TraceBuilderEngine.java	Wed Jun 23 14:35:40 2010 +0300
@@ -0,0 +1,47 @@
+/*
+* Copyright (c) 2007 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:
+*
+* Base class for all engine classes
+*
+*/
+package com.nokia.tracebuilder.engine;
+
+import com.nokia.tracebuilder.model.TraceBuilderException;
+
+/**
+ * Base class for all engine classes
+ * 
+ */
+public abstract class TraceBuilderEngine {
+
+	/**
+	 * Called after trace project has been opened
+	 */
+	public abstract void projectOpened();
+
+	/**
+	 * Called when trace project is closed
+	 */
+	public abstract void projectClosed();
+
+	/**
+	 * Called when exporting the project
+	 * 
+	 * @throws TraceBuilderException
+	 *             if export fails
+	 */
+	public abstract void exportProject() throws TraceBuilderException;
+
+}