(Quick Reference)



The response object is an instance of the Servlet API’s HttpServletResponse class.


class BookController {
    def downloadFile() {
        byte[] bytes = // read bytes
        response.outputStream << bytes


The Servlet API’s HttpServletResponse class can be used within Grails to perform all typical activities such as writing out binary data, writing directly to the response and sending error response codes to name but a few. Refer to the documentation on the HttpServletResponse class in the Servlet API for more information.

The additional methods added to the response object are documented in the Grails Servlet API reference guide