How to use PrimeFaces p:fileUpload? Listener method is never invoked or UploadedFile is null / throws an error / not usable

Question

I\'m trying to upload a file using PrimeFaces, but the fileUploadListener method isn\'t being invoked after the upload finishes.

Here is the view:

Answer 1

Neither of the suggestions here were helpful for me. So I had to debug primefaces and found the reason of the problem was:

java.lang.IllegalStateException: No multipart config for servlet fileUpload

Then I have added section into my faces servlet in the web.xml. So that has fixed the problem:

    main

        org.apache.myfaces.webapp.MyFacesServlet
        1
        
            /tmp
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            418018841
            1048576