FileUpload - Single Single mode allows only one file to be selected at a time from the native file dialog.
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<h:form>
    <p:fileUpload fileUploadListener="#{fileUploadView.handleFileUpload}" mode="advanced" dragDropSupport="false"
           update="messages" sizeLimit="100000" fileLimit="3" allowTypes="/(\.|\/)(gif|jpe?g|png)$/" />

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