Liferay's success or failure messages for user feedback and custom aui validator

 view.jsp:

<liferay-ui:success key="entity-updated-successfully" message="successfully-updated-entity-details"/>

<liferay-ui:error key="entity-updation-failed" message="failed-updation-entity-details"/>

Custom AUI Validator:

<aui:input name="title">

<aui:validator errorMessage="please-specify-file" name="custom" >

function (val, fieldNode, ruleVal){

    return     ((val!='') || A.one('#<portlet:namespace/>file').val() != '');

}

</aui:validator>

</aui:input>