Question

I’m unable to pack taglibrary in a war file. I moved tags from project to extra library the current project is depending now. I put the taglibrary file into the META-INF directory of the jar containing tags (how is described here). But the page does not work:

Expression Error: Named Object: eu.barbucha.barbatag.simple.PropertyTag not found.

The server is able to find the taglibrary. Otherwise the page works, just one waring appears:

Warning: This page calls for XML namespace http://barbucha.eu/tags declared with prefix br but no taglibrary exists for that namespace.

Thus the question is: Why the server finds just the descriptor, but not the classes? When I copy classes from WEB-INF/lib/barbatag.jar into WEB-INF/classes and restart the webapp in administration console, the page gets working. The server also finds UI-components only if they are involved directly in classes of the applictation, but not in the jar stored in the WEB-INF/lib directory. On other hand the server loads taglib descriptor from the jar. It’s really confusing… Declaration of the critical class:

package eu.barbucha.barbatag.simple;    

@FacesComponent("eu.barbucha.barbatag.simple.PropertyTag")
public class PropertyTag extends UIComponentBase { ... }

Definition of critical tag:

<tag>
    <display-name>The component taking values from a property file</display-name>
    <tag-name>property</tag-name>
    <component>
        <component-type>eu.barbucha.barbatag.simple.PropertyTag</component-type>
    </component>
</tag>

One potentionally important point: I’m using Spring MVC.

Answer 1

You need to supply a /META-INF/faces-config.xml file in the JAR in order to get JSF to scan the JAR file for classes with JSF specific annotations like @FacesComponent. This is done so to prevent JSF from unnecessarily scanning every single JAR file for classes (which might be very time and CPU consuming if you have lot of them).