Bug 173224 [regression] preview attached report caused data exception
steps to reproduce: - preview attached report within deployed birt report viewer expected behavior: - report is rendered properly actual behavior: - exception thrown in console, although report was rendered
viewer/org.eclipse.birt.report.viewer/birt/WEB-INF/classes/org/eclipse/birt/report/service/actionhandler/BirtGetCascadeParameterActionHandler.java
assert attrBean != null;
		Oprand[] params = operation.getOprand( );
		Map paramMap = new LinkedHashMap( );
		InputOptions options = new InputOptions( );
		options.setOption( InputOptions.OPT_REQUEST, context.getRequest( ) );
		IViewerReportDesignHandle designHandle = attrBean
				.getReportDesignHandle( context.getRequest( ) );
		Map cascParamMap = null;
		for ( int i = 0; i < params.length; i++ )
		{
			Oprand param = params[i];
			String paramName = param.getName( );
			boolean isLocale = false;
			
			if ( ParameterAccessor.PARAM_ISNULL.equalsIgnoreCase( paramName ) )
			{
				paramMap.put( param.getValue( ), null );
				continue;
			}
			else if ( paramName.startsWith( ParameterAccessor.PREFIX_ISLOCALE ) )
			{
				
				paramName = paramName.replaceFirst(
						ParameterAccessor.PREFIX_ISLOCALE, "" ); 
				isLocale = true;
			}
			
			ParameterDefinition parameter = attrBean
					.findParameterDefinition( paramName );
			if ( parameter == null )