getting original file name of uploaded file grails
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I am getting the uploaded file using request.getFile("file") where "file" is the name of file input element in my gsp file. I am able to parse this file fine but when I try to get the file's original name, I encounter the following error 

No signature of method: org.springframework.web.multipart.commons.CommonsMultipartFile.getOriginalFileName() is applicable for argument types: () values: []
Possible solutions: getOriginalFilename()

This is my code:

    def f = request.getFile("file")
    def name = f.getOriginalFileName()

Why can't I call the getOriginalFileName() method on 'f', I thought request.getFile() returned a MultipartFile object