Bug 162841 [regression]Drill-through link to document containing parameters failed in html and pdf
Description: Drill-through link to document containing parameters failed in html and pdf Steps to reproduce: 1. New a report with a report parameter, don't set default value for it. 2. Preview in Web Viewer, input parameter value and save the report document to c:\ 3. New another report, insert a label, set a drill through link on the label, link to the report document. 4. Preview in web viewer, html and pdf, click the link. Expected result: Link to target report. Actual result: In html, a dialog popped up and said "a runtime error has occurred" In pdf, a dialog popped up and said that report parameter has null value. In frameset servlet, both formats are ok. I found that if I set default value for the report parameter in target report, the issue will disappear.
viewer/org.eclipse.birt.report.viewer/birt/WEB-INF/classes/org/eclipse/birt/report/context/ViewerAttributeBean.java
}
			}
			else
			{
				params.put( paramName, null );
			}
		}
		return params;
	}
	/**
	 * get parameter object.
	 * 
	 * @param request
	 *            HttpServletRequest
	 * @param parameter
	 *            ScalarParameterHandle
	 * 
	 * @return
	 */
	protected Object getParamValueAsString( HttpServletRequest request,
			ScalarParameterHandle parameter )
	{
		String paramName = parameter.getName( );
		String paramValue = null;
		if ( ParameterAccessor.isReportParameterExist( request, paramName ) )
		{
			
			paramValue = ParameterAccessor.getReportParameter( request,
					paramName, null );
			return paramValue;