MyFaces datatable columnClasses strange behaviour

Question

I've recently changed from TomEE 1.5.2 to 1.6.0 which has upgraded MyFaces from 2.1.10 to 2.1.13. I'm now seeing unusual results in dataTable column styles.

This works fine:

<h:dataTable value="#{testView.dataList}" var="r" columnClasses="col1,col2,col3,col4">
    <h:column><f:facet name="header">Col 1</f:facet>#{r.col1}</h:column>
    <h:column><f:facet name="header">Col 2</f:facet>#{r.col2}</h:column>
    <h:column><f:facet name="header">Col 3</f:facet>#{r.col3}</h:column>
    <h:column><f:facet name="header">Col 4</f:facet>#{r.col4}</h:column>
</h:dataTable>

If, however, the columns have a rendered attribute which evaulates to false then the column class gets messed up.

<h:dataTable value="#{testView.dataList}" var="r" columnClasses="col1,col2,col3,col4">
    <h:column><f:facet name="header">Col 1</f:facet>#{r.col1}</h:column>
    <h:column><f:facet name="header">Col 2</f:facet>#{r.col2}</h:column>
    <h:column rendered="false"><f:facet name="header">Col 3</f:facet>#{r.col3}</h:column>
    <h:column><f:facet name="header">Col 4</f:facet>#{r.col4}</h:column>
</h:dataTable>

gives

<tr>
    <td class="col1">col1</td>
    <td class="col2">col2</td>
    <td class="col3">col4</td>
</tr>

Column 3 has not been rendered as expected, but column 4 has been given the col3 style instead of the col4 one. As I said it work as I was expecting prior to 2.1.13, so do you think this is a MyFaces bug?

Answer 1

It is not a bug, instead by spec, columnClasses is applied sequentially to the active columns. It was a fix in MYFACES-3749, but I checked it with the latest version of Mojarra and it works the same.

My suggestion is use tomahawk extended datatable, that works just like h:datatable but with some extended features. In your case you can set the styleClass of the column in this way.

<t:datatable var="row" ...>
   <t:column styleClass="#{row.styleClass}">
   ...
   </t:column>
</t:datatable>

This issue has been already reported in the spec. See JAVASERVERFACES_SPEC_PUBLIC-217.