"Could not create renderer with alias..." after deploying ResourceRenderer

Question

Hello everybody
I've developed a custom ResourceRenderer class that looks like this:
package no.expert.portal.km.relateddocs;
import com.sapportals.htmlb.Component;
import com.sapportals.htmlb.Link;
import com.sapportals.wcm.WcmException;
import com.sapportals.wcm.rendering.resource.cm.ResourceRenderer;
import com.sapportals.wcm.repository.IResource;
public class RelatedDocsNamePropertyRenderer extends ResourceRenderer
     protected Component renderContentLink(com.sapportals.htmlb.Component comp) throws WcmException
          Link result = (Link) super.renderContentLink(comp);
          result.setTarget("");
          return result;
     protected Component renderContentLink(IResource resource, com.sapportals.htmlb.Component comp) throws WcmException
          Link result = (Link)super.renderContentLink(resource, comp);
          result.setTarget("");
          return result;
All it does, really, is preventing links to documents in KM to open in a new window. At least that's what I'm hoping it will do, as it's based on ideas in <a href="https://www.sdn.sap.com/irj/sdn/thread?threadID=20316">this post</a>.
I've added all the necessary .jar files, and implemented a wrapper portal service as described here: <a href="http://media.sdn.sap.com/html/submitted_docs/nw_kmc/ide/projects/Setting%20Up%20a%20KMC%20Project.html">http://media.sdn.sap.com/html/submitted_docs/nw_kmc/ide/projects/Setting%20Up%20a%20KMC%20Project.html</a>.
I've created an alias for the class in <i>Content Management -> User Interface -> Mapping</i>, and assigned this to the resource renderer settings that I use.
OK, here is where the trouble starts. When viewing the layout set with debugging on, I check <i>Rendering Information</i>. It informs me that <i>"The given configuration was not used, because the alias is not defined or points to an invalid java class"</i>. Looking in the log, this is the error message:
Could not create renderer with alias ZRelatedDocsNameResourceRender and classname no.expert.portal.km.relateddocs.RelatedDocsNamePropertyRenderer:java.lang.NoClassDefFoundError: com/sapportals/wcm/rendering/resource/cm/ResourceRenderer
------------------------- Loader Info -------------------------
ClassLoader name: [com.sapportals.portal.prt.util.ApplicationClassLoader@6b247b]
Parent loader name: [com.sapportals.portal.prt.util.ApplicationClassLoader@4e82c4]
References:
   not registered!
Resources:
   C:usrsapEPUJC00j2eeclusterserver0appssap.comirjservlet_jspirjrootWEB-INFportalportalappsno.expert.portal.km.relateddocs.RelatedDocsNamePropertyRendererprivatelibno.expert.portal.km.relateddocs.RelatedDocsNamePropertyRenderercore.jar
The error occurred while trying to load "no.expert.portal.km.relateddocs.RelatedDocsNamePropertyRenderer".
     at com.sap.engine.frame.core.load.ReferencedLoader.loadClass(ReferencedLoader.java:389)
I have a suspicion this might have something to do with the SharingRefernce in portalapp.xml, but after experimenting with different values, I'm no nearer a solution. Any ideas, anyone? Any help greatly appreciated.
-martin
Yes, and here is my portalapp.xml:
<?xml version="1.0" encoding="utf-8"?>
<application>
  <application-config>
    <property name="SharingReference" value="com.sap.netweaver.bc.crt,knowledgemanagement"/>
    <property name="PrivateSharingReference" value="com.sap.km.cm.ui.flex"/>
  </application-config>
  <components>
    <component name="RelatedDocsNamePropertyRenderer">
      <component-config>
        <property name="ClassName" value="no.expert.portal.km.relateddocs.RelatedDocsNamePropertyRenderer"/>
      </component-config>
      <component-profile/>
    </component>
  </components>
  <services>
    <service name="BootStrapNamePropertyRender">
      <service-config>
        <property name="className" value="no.expert.portal.km.relateddocs.BootStrapNamePropertyRender"/>
        <property name="startup" value="true"/>
      </service-config>
    </service>
  </services>
</application>

Answer 1

Hi Gourab,
Double check the the page.xml has referring to the correct CO. Open the page.xml and see which controller is attached to it.
Also attach the extended controller through personalization to the page/Region.
Thanks
--Anil