def filter = {
        if(!params.max) params.max = 10
        if(params?.format && params.format != "html"){
            response.contentType = grailsApplication.config.grails.mime.types[params.format]
            response.setHeader("Content-disposition", "attachment; filename=books.${params.extension}")

            exportService.export(params.format, response.outputStream,filterPaneService.filter( params, Book ), [:], [:])
        }
        render( view:'list',
            model:[ bookInstanceList: filterPaneService.filter( params, Book ),
            bookInstanceTotal: filterPaneService.count( params, Book ),
            filterParams: FilterPaneUtils.extractFilterParams(params),
            params:params ] )
    }