I ‘m using Primefaces to upload files, I want to check the size of all the files that will be uploaded if the size is over the limit. I’ve managed to check the size of all files but I cant display any message.

FI: the check of file type is working and the message warning is displayed.
the scroll also is working.

What can I do?

    
 <p:fileUpload id="attachmentUpload"
                                      fileUploadListener="#{documentLibrary.checkFileSize}"
                                      label="#{msg.upload}"
                                      mode="advanced" multiple="true" styleClass="fileupload-buttonbar-white"
                                      auto="true" update="attachmentPanel"
                                      onstart="#{request.requestURI.contains('document/edit') ? 'PF('editWidgetVar').disable(), PF('documentWizardWidgetVar').hideNextNav(), PF('documentWizardWidgetVar').hideBackNav()' : 'PF('documentWizardWidgetVar').hideNextNav(), PF('documentWizardWidgetVar').hideBackNav()'}"
                                      oncomplete="#{request.requestURI.contains('document/edit') ? 'PF('editWidgetVar').enable(), PF('outgoingDocumentWizardWidgetVar').showNextNav(), PF('outgoingDocumentWizardWidgetVar').showBackNav()' : 'PF('outgoingDocumentWizardWidgetVar').showNextNav(), PF('outgoingDocumentWizardWidgetVar').showBackNav()'}"
                                      invalidFileMessage="#{of:format1(val['invalid_file_type'], documentLibrary.allowedExtensions)}"
                                      allowTypes="#{documentLibrary.allowedExtensions}"
                                       />
                        <p:message id="fileWarnMessage" for="attachmentUpload" autoUpdate="true" />

and

public void checkFileSize(FileUploadEvent event) {
    ...
        if(size > sizeLimit){
            //MessageUtils.createBasicMessage("annex_exceed_3Mb", FacesMessage.SEVERITY_WARN, "form:documentEditComponent:attachmentUpload");
            FacesContext.getCurrentInstance().addMessage("form:documentEditComponent:attachmentUpload", MessageUtils.createMessage("validation.messages", "file_exceed_limit", FacesMessage.SEVERITY_WARN));
            PrimeFaces.current().ajax().update("form:documentEditComponent:attachmentUpload");
            PrimeFaces.current().scrollTo("form:documentEditComponent:attachmentUpload");
        }
}