Bug 180118 Enhance to print out source stack trace in preview mode.[0002]
viewer/org.eclipse.birt.report.viewer/birt/WEB-INF/classes/org/eclipse/birt/report/servlet/BirtEngineServlet.java
* @return
	 */
	protected void __init( ServletConfig config )
	{
		BirtReportServiceFactory.init( new BirtViewerReportService( config
				.getServletContext( ) ) );
		engine = new EngineFragment( );
		requester = new RequesterFragment( );
		requester.buildComposite( );
		requester.setJSPRootPath( "/webcontent/birt" ); 
	}
	/**
	 * Init context.
	 * 
	 * @param request
	 *            incoming http request
	 * @param response
	 *            http response
	 * @exception BirtException
	 * @return IContext
	 */
	protected IContext __getContext( HttpServletRequest request,
			HttpServletResponse response ) throws BirtException
	{
		InputOptions options = new InputOptions( );
		options.setOption( InputOptions.OPT_REQUEST, request );
		BirtReportServiceFactory.getReportService( ).setContext(
				getServletContext( ), options );
		return new BirtContext( request, response );
	}