I've just tested with the Trinidad inputFile component, on Safari 2.0 and Firefox 2.0, and both via PPR and without PPR, and the code correctly identified zero-byte file as a zero-byte file, and the lack of a file as "null".
As Volker points out, when the user manually types in a file name that doesn't really exist, you get a zero-byte file delivered to the server, and there's nothing we can do about that. (I'd thought the question was what happens when there is no file entered at all, where the only correct behavior is null, and we do that.) So, as best as I can see, Trinidad is doing all the right things here. -- Adam On 7/27/07, Adam Winer <[EMAIL PROTECTED]> wrote: > Hrm, disturbing... but it might be possible to do some DOM hacking > on the client to set an input type="hidden" flag that inputFile could check. > I'll have a look. > > -- Adam > > > On 7/27/07, Volker Weber <[EMAIL PROTECTED]> wrote: > > Hi, > > > > there is no chance on the server to distinguish between an empty file and a > > non existing file. In FF and IE the generated request is the same. > > > > see also > > http://www.nabble.com/-FileUpload--Detecting-empty-file-vs.-bad-path-t2122968.html#a5888362 > > > > The only we can do on the server is checking the filename, an uploaded > > file has a filename. > > > > > > Regards, > > Volker > > > > > > > > 2007/7/26, Piotr Pikusa <[EMAIL PROTECTED]>: > > > Yes there is a contentType of file type not recognized by server. The > > > problem is, that InputFile doesn't return null if file doesn't exist. What > > > is more UploadFile dosen't have a method to check it. So I can even get > > > InputStream from UploadFile object with length = 0. There is no way to > > > differ an empty file from not existing file. So I wonder if it is a bug. > > > > > > -----Original Message----- > > > From: Volker Weber [mailto:[EMAIL PROTECTED] > > > Sent: Thursday, July 26, 2007 12:51 PM > > > To: MyFaces Discussion > > > Subject: Re: [Trinidad] How to check if file exists using InputFile > > > compon ent? > > > > > > > > > Hi, > > > > > > is there a contentType if the file does not exists? > > > > > > > > > Regards, > > > Volker > > > > > > 2007/7/26, Piotr Pikusa <[EMAIL PROTECTED]>: > > > > Thank you for reply. Unfortunately your method doesn't work with > > > > org.apache.myfaces.trinidad.model.UploadedFile object returned by > > > InputFile. > > > > UploadFile has a method getFilename() which returns name given by user. > > > > It > > > > still doesn't check if file exists, so it is not a name of real file. So > > > the > > > > problem still isn't solved. > > > > > > > > -----Original Message----- > > > > From: Volker Weber [mailto:[EMAIL PROTECTED] > > > > Sent: Thursday, July 26, 2007 11:40 AM > > > > To: MyFaces Discussion > > > > Subject: Re: [Trinidad] How to check if file exists using InputFile > > > > compon ent? > > > > > > > > > > > > Hi Piotr, > > > > > > > > i don't know the tomahawk InputFile component, but maybe you can check > > > > the uploaded filename? > > > > > > > > In tobago we check the filename to determine if a file was uploaded: > > > > > > > > if (file == null || file.getName().length() == 0) { > > > > addErrorMessage(facesContext); > > > > setValid(false); > > > > } > > > > > > > > > > > > Regards, > > > > Volker > > > > > > > > > > > > 2007/7/26, Piotr Pikusa <[EMAIL PROTECTED]>: > > > > > In many toutorials about InputFile component (e.g on Oracle and > > > > > Trinidad > > > > > sites) there is if instruction to check if uploadFile is not null. But > > > it > > > > > would never be null, event if the file doesn't exist. Is it a bug in > > > > > compoment? Is there any way to check file existence using InputFile > > > > > component? > > > > > > > > > > > > > > > -----Original Message----- > > > > > From: Piotr Pikusa [mailto:[EMAIL PROTECTED] > > > > > Sent: Wednesday, July 25, 2007 3:10 PM > > > > > To: 'MyFaces Discussion' > > > > > Subject: RE: [Trinidad] How to check if file exists using InputFile > > > compon > > > > > ent? > > > > > > > > > > > > > > > Unfotunately not. If the existing file is empty the getLength() method > > > > > returns 0 too. So the problem isn't still solved. > > > > > > > > > > > > > > > Matthias Wessendorf wrote: > > > > > > > > > > hi piotr, > > > > > > > > > > the UploadedFile interfaces has a getLength() method > > > > > > > > > > it's 0, when the file isn't there.. > > > > > > > > > > -M > > > > > > > > > > On 7/25/07, Piotr Pikusa <[EMAIL PROTECTED]> wrote: > > > > > > Hey! > > > > > > > > > > > > As it is mentioned in the subject I wonder if there is any > > > > > > possibility > > > > to > > > > > > check file existence. > > > > > > I got this code on my jsp page: > > > > > > > > > > > > [code] > > > > > > > > > > > > <tr:inputFile > > > > > > required="true" > > > > > > rendered="true" > > > > > > label="Load File:" > > > > > > value="#{backingBean.file}" > > > > > > /> > > > > > > <af:commandButton > > > > > > text="#{"Button"}" > > > > > > action="#{backingBean.importFile}" /> > > > > > > > > > > > > [/code] > > > > > > > > > > > > which bind the value to the file property. The type of file is > > > > UploadFile. > > > > > > In backingBean I have this code: > > > > > > > > > > > > [code] > > > > > > > > > > > > UploadFile file; > > > > > > > > > > > > public void importFile(){ > > > > > > if(file != null) { > > > > > > doSomeAction(); > > > > > > } > > > > > > else{ > > > > > > returnError(); > > > > > > } > > > > > > } > > > > > > > > > > > > public UploadedFile getFile() { > > > > > > return file; > > > > > > } > > > > > > > > > > > > public void setFile(UploadedFile file) { > > > > > > this.file = file; > > > > > > } > > > > > > > > > > > > [/code] > > > > > > > > > > > > The point of the problem is that the file is never null, no matter > > > > > > if > > > > file > > > > > > exists or not. If file doesn't exist the InputFile component doesn't > > > > > return > > > > > > null. The UploadFile doesn't have a method to check file existence. > > > > > > So my question is when file property can be null. And how to check > > > > > > if > > > > file > > > > > > exists using InputFile component and UploadFile object? (I cannot > > > > > > use > > > > > other > > > > > > type, but UploadFile). > > > > > > > > > > > > > > > > > > > > > -- > > > > > Matthias Wessendorf > > > > > > > > > > further stuff: > > > > > blog: http://matthiaswessendorf.wordpress.com/ > > > > > mail: matzew-at-apache-dot-org > > > > > > > > > > > > > > >
