public static boolean isRequestSource(UIComponent component, FacesContext context) {
        String partialSource = context.getExternalContext().getRequestParameterMap().get(Constants.RequestParams.PARTIAL_SOURCE_PARAM);
        return component.getClientId(context).equals(partialSource);
    }
Creates an RFC 6266 Content-Dispostion header following all UTF-8 conventions.
<p>
@param value e.g. "attachment"
@param filename the name of the file
@return a valid Content-Disposition header in UTF-8 format
primefaces/src/main/java/org/primefaces/util/ComponentUtils.java