Miscellaneous JSF problems

Miscellaneous JSF problems

Altough they are not all specific to Nuxeo framework, here are some troubleshooting issues that can be encountered with JSF.

NullPointerException? when rendering a page

If you have a stack trace that looks like:

java.lang.NullPointerException
        at org.apache.myfaces.trinidadinternal.renderkit.core.xhtml.FormRenderer.encodeEnd(FormRenderer.java:210)
        at org.apache.myfaces.trinidad.render.CoreRenderer.encodeEnd(CoreRenderer.java:211)
        at org.apache.myfaces.trinidadinternal.renderkit.htmlBasic.HtmlFormRenderer.encodeEnd(HtmlFormRenderer.java:63)
        at javax.faces.component.UIComponentBase.encodeEnd(UIComponentBase.java:833)
        at javax.faces.component.UIComponent.encodeAll(UIComponent.java:896)
        at javax.faces.component.UIComponent.encodeAll(UIComponent.java:892)

Then you probably have a <h:form> tag inside another <h:form> tag, and this is not allowed.

My action is not called when clicking on a button

If an action listener is not called when clicking on a form button, then you probably have conversion or validation errors on the page. Add a <h:messages /> tag to your page to get more details on the actual problem.

Also make sure you don't have any <h:form> tag inside another <h:form> tag.

My file is not uploaded correctly although other fields are set

Make sure your <h:form> tag accepts multipart content: <h:form enctype="multipart/form-data">.

My ajax action does not work

There could be lots of reasons for this to happen. The easiest way to find the cause is to add a <a4j:log /> tag to your xhtml page, and then open it using CTRL+SHIFT+l. You'll get ajax debug logs in a popup window and hopefully will understand what is the problem.

Also make your you have the right namespace: xmlns:a4j="https://ajax4jsf.dev.java.net/ajax"