Bug 147407 Preview the attached report in the web viewer first time and then click the TOC button will cause NPE error
Description: It just can be reprouduced at first time preview. Step to reproduce: 1. please use attach report file 2. preview it in the web viewer 3. click the "Toggle table of contents" button Actual result: As the atteched screenshot shows,There is a NPE error.And if you preview it in the Web viewer again, the phenomenon is disappear.But reopen the eclipse and preview it at first time, it will be occured.
viewer/org.eclipse.birt.report.viewer/birt/WEB-INF/classes/org/eclipse/birt/report/utility/ParameterAccessor.java
return page <= 0 ? 1 : page; 
	}
	/**
	 * Get reportlet id from Http request.
	 * 
	 * @param request
	 *            http request
	 * @return reportlet id
	 */
	public static String getInstanceId( HttpServletRequest request )
	{
		return getParameter( request, PARAM_INSTANCEID );
	}
	/**
	 * Get named parameters from http request. parameter names and values are
	 * all in iso-8859-1 format in request.
	 * 
	 * @param request
	 *            incoming http request
	 * @param parameterName
	 *            parameter name in UTF-8 format
	 * @return named parameters from http request
	 */
	public static Set getParameterValues( HttpServletRequest request,
			String parameterName )
	{
		return getParameterValues( request, parameterName, true );
	}
	/**
	 * Get report file name.