JSF AJAX Update Guidelines

Critical Rules

1. AJAX UPDATE RULE: NEVER use plain HTML elements (div, span) with id attributes for AJAX updates - use JSF components (h:panelGroup, p:outputPanel) instead
2. RENDERED ATTRIBUTE RULE: NEVER use rendered on plain HTML elements - JSF ignores it; use h:panelGroup layout="block" instead
3. COMPONENT REFERENCES: Use p:resolveFirstComponentWithId for updates: update=":#{p:resolveFirstComponentWithId('componentId',view).clientId}"
4. NO CSS/jQuery SELECTORS: NEVER use @(.class), @(#id), @parent in update or process attributes. Use @this, @form, explicit IDs, or :#{p:resolveFirstComponentWithId(...)}

Wrong vs Correct

<!-- WRONG - Plain HTML, AJAX silently fails -->
<div id="stockSelection">
    <!-- content -->
</div>
<p:commandButton update="stockSelection" />

<!-- CORRECT - JSF component, AJAX works -->
<h:panelGroup id="stockSelection">
    <div><!-- content --></div>
</h:panelGroup>
<p:commandButton update="stockSelection" />

Updating Growl/Messages

The growl component is in template.xhtml outside forms. Use absolute ID with colon prefix:

<!-- CORRECT -->
<p:commandButton action="#{bean.save}" update="myTable :growl" />

<!-- WRONG - Do NOT use CSS selectors -->
<p:commandButton update="@(.ui-growl)" />

JSF Components for AJAX Updates

• h:panelGroup - Lightweight wrapper, no HTML output
• p:outputPanel - PrimeFaces panel, renders as <span> or <div>
• h:div - Renders as HTML <div>
• h:form - For updating entire form sections
• p:panel - Full-featured panel with header/footer

Debugging

1. Check browser console for JavaScript errors
2. Verify target element is a JSF component (not plain HTML)
3. Use browser dev tools to confirm JSF-generated id
4. Test with h:panelGroup wrapper if updates fail
5. Check component hierarchy - nested components affect id resolution

For complete reference, read developer_docs/jsf/ajax-update-guidelines.md.