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/utility/BirtUtility.java
*/
	public static void handleOperation( Operation operation,
			ViewerAttributeBean bean, Map parameterMap, Map displayTexts )
			throws Exception
	{
		if ( operation == null || bean == null || parameterMap == null
				|| displayTexts == null )
			return;
		
		List locs = new ArrayList( );
		Map params = new HashMap( );
		String displayTextParam = null;
		Oprand[] oprands = operation.getOprand( );
		for ( int i = 0; i < oprands.length; i++ )
		{
			String paramName = oprands[i].getName( );
			Object paramValue = oprands[i].getValue( );
			if ( paramName == null || paramValue == null )
				continue;
			if ( paramName.equalsIgnoreCase( ParameterAccessor.PARAM_ISLOCALE ) )
			{
				
				locs.add( paramValue );
			}
			
			else if ( ParameterAccessor.PARAM_ISNULL
					.equalsIgnoreCase( paramName ) )
			{
				
				parameterMap.put( paramValue, null );