Bug 176786 Issue when use ${env.working.folder} as context path.[0601]
Description: Issue when use ${env.working.folder} as context path Build number:2.2.0.v20070308 Steps to reproduce: 1. Add environment variable as below: env.working.folder(D:\temp\working_folder) env.document.folder (D:\temp\document_folder) env.image.folder(D:\temp\image_folder) 2. Deploy WebViewerExample folder in Tomcat5.5.7 2. Set context parameter as attached with form like ${env.working.folder}. 3. Start Server Expected result: Content inside WebViewerExample folder is untouched. Actual result: After server is started, refresh and check the WebViewerExample folder. Only webcontent and WEB-INF folders are left, other folders and two sample reports disappear. Error log:N/A
viewer/org.eclipse.birt.report.viewer/birt/WEB-INF/classes/org/eclipse/birt/report/utility/ParameterAccessor.java
if ( value == null || value.length( ) <= 0 ) 
		
		{
			value = ""; 
		}
		Map paramMap = request.getParameterMap( );
		String ISOName = toISOString( name );
		if ( paramMap == null || !paramMap.containsKey( ISOName ) )
		{
			value = defaultValue;
		}
		Set nullParams = getParameterValues( request, PARAM_ISNULL );
		if ( nullParams != null && nullParams.contains( name ) )
		{
			value = null;
		}
		return value;
	}
	/**
	 * Get result set name.
	 * 
	 * @param request
	 * @return
	 */
	public static String getResultSetName( HttpServletRequest request )
	{
		return getReportParameter( request, PARAM_RESULTSETNAME, null );
	}
	/**
	 * Get solected column name list.