FileUpload - Auto Upload process begins once the file is selected in auto mode.
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<h:form>
    <p:fileUpload fileUploadListener="#{fileUploadView.handleFileUpload}" mode="advanced" 
                     update="messages" auto="true" sizeLimit="100000" allowTypes="/(\.|\/)(gif|jpe?g|png)$/" />

    <p:growl id="messages" showDetail="true" />
</h:form>
                
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