diff --git a/webapp/config/web.xml b/webapp/config/web.xml
index 17709593a..524e55bc7 100644
--- a/webapp/config/web.xml
+++ b/webapp/config/web.xml
@@ -924,6 +924,36 @@
     <servlet-class>edu.cornell.mannlib.vitro.webapp.controller.BrowseController</servlet-class>
     <load-on-startup>5</load-on-startup>
   </servlet>
+  
+  <servlet>
+    <servlet-name>browsecontrollerJsp</servlet-name>
+    <servlet-class>edu.cornell.mannlib.vitro.webapp.controller.BrowseControllerJsp</servlet-class>
+    <load-on-startup>5</load-on-startup>
+  </servlet>
+  
+  <servlet>
+    <servlet-name>browsecontrollerStringTemplate</servlet-name>
+    <servlet-class>edu.cornell.mannlib.vitro.webapp.controller.BrowseControllerStringTemplate</servlet-class>
+    <load-on-startup>5</load-on-startup>
+  </servlet>
+  
+  <servlet>
+    <servlet-name>browsecontrollerFreeMarker</servlet-name>
+    <servlet-class>edu.cornell.mannlib.vitro.webapp.controller.BrowseControllerFreeMarker</servlet-class>
+    <load-on-startup>5</load-on-startup>
+  </servlet>
+  
+  <servlet>
+    <servlet-name>browsecontrollerVelocity</servlet-name>
+    <servlet-class>edu.cornell.mannlib.vitro.webapp.controller.BrowseControllerVelocity</servlet-class>
+    <load-on-startup>5</load-on-startup>
+  </servlet>
+  
+  <servlet>
+    <servlet-name>browsecontrollerWicket</servlet-name>
+    <servlet-class>edu.cornell.mannlib.vitro.webapp.controller.BrowseControllerWicket</servlet-class>
+    <load-on-startup>5</load-on-startup>
+  </servlet>
 
   <servlet>
     <servlet-name>pubsbyorg</servlet-name>
@@ -1033,6 +1063,30 @@
     <servlet-name>browsecontroller</servlet-name>
     <url-pattern>/browsecontroller</url-pattern>
   </servlet-mapping>
+  <servlet-mapping>
+    <servlet-name>browsecontroller</servlet-name>
+    <url-pattern>/browsecontroller</url-pattern>
+  </servlet-mapping>
+  <servlet-mapping>
+    <servlet-name>browsecontrollerJsp</servlet-name>
+    <url-pattern>/browsecontroller-jsp</url-pattern>
+  </servlet-mapping>
+  <servlet-mapping>
+    <servlet-name>browsecontrollerStringTemplate</servlet-name>
+    <url-pattern>/browsecontroller-stringtemplate</url-pattern>
+  </servlet-mapping>
+  <servlet-mapping>
+    <servlet-name>browsecontrollerFreeMarker</servlet-name>
+    <url-pattern>/browsecontroller-freemarker</url-pattern>
+  </servlet-mapping>
+  <servlet-mapping>
+    <servlet-name>browsecontrollerVelocity</servlet-name>
+    <url-pattern>/browsecontroller-velocity</url-pattern>
+  </servlet-mapping>
+  <servlet-mapping>
+    <servlet-name>browsecontrollerWicket</servlet-name>
+    <url-pattern>/browsecontroller-wicket</url-pattern>
+  </servlet-mapping>
   <servlet-mapping>
     <servlet-name>pubsbyorg</servlet-name>
     <url-pattern>/pubsbyorg</url-pattern>
diff --git a/webapp/src/edu/cornell/mannlib/vitro/webapp/controller/BrowseControllerFreeMarker.java b/webapp/src/edu/cornell/mannlib/vitro/webapp/controller/BrowseControllerFreeMarker.java
new file mode 100644
index 000000000..ebf88a213
--- /dev/null
+++ b/webapp/src/edu/cornell/mannlib/vitro/webapp/controller/BrowseControllerFreeMarker.java
@@ -0,0 +1,329 @@
+/* $This file is distributed under the terms of the license in /doc/license.txt$ */
+
+package edu.cornell.mannlib.vitro.webapp.controller;
+
+import com.hp.hpl.jena.ontology.OntModel;
+import com.hp.hpl.jena.rdf.listeners.StatementListener;
+import com.hp.hpl.jena.rdf.model.Statement;
+import com.hp.hpl.jena.vocabulary.RDF;
+import edu.cornell.mannlib.vitro.webapp.beans.ApplicationBean;
+import edu.cornell.mannlib.vitro.webapp.beans.Portal;
+import edu.cornell.mannlib.vitro.webapp.beans.VClass;
+import edu.cornell.mannlib.vitro.webapp.beans.VClassGroup;
+import edu.cornell.mannlib.vitro.webapp.dao.VClassGroupDao;
+import edu.cornell.mannlib.vitro.webapp.dao.VitroVocabulary;
+import edu.cornell.mannlib.vitro.webapp.dao.WebappDaoFactory;
+import edu.cornell.mannlib.vitro.webapp.dao.filtering.WebappDaoFactoryFiltering;
+import edu.cornell.mannlib.vitro.webapp.dao.filtering.filters.VitroFilterUtils;
+import edu.cornell.mannlib.vitro.webapp.dao.filtering.filters.VitroFilters;
+import edu.cornell.mannlib.vitro.webapp.flags.PortalFlag;
+import org.apache.commons.logging.Log;
+import org.apache.commons.logging.LogFactory;
+import org.joda.time.DateTime;
+
+import javax.servlet.RequestDispatcher;
+import javax.servlet.ServletContext;
+import javax.servlet.ServletException;
+import javax.servlet.http.HttpServletRequest;
+import javax.servlet.http.HttpServletResponse;
+import java.io.IOException;
+import java.util.*;
+import java.util.concurrent.ConcurrentHashMap;
+import java.util.concurrent.ConcurrentLinkedQueue;
+
+
+public class BrowseControllerFreeMarker extends BrowseController {
+    static final long serialVersionUID=2006030721126L;
+
+    private transient ConcurrentHashMap<Integer, List> _groupListMap
+            = new ConcurrentHashMap<Integer, List>();
+    private transient ConcurrentLinkedQueue<String> _rebuildQueue
+            = new ConcurrentLinkedQueue<String>();
+    private RebuildGroupCacheThread _cacheRebuildThread;
+
+    private static final Log log = LogFactory.getLog(BrowseController.class.getName());
+
+    public void init(javax.servlet.ServletConfig servletConfig)
+            throws javax.servlet.ServletException {
+        super.init(servletConfig);
+        ServletContext sContext = servletConfig.getServletContext();
+
+        //BJL23: I'll work on a strategy for avoiding all this craziness.
+        OntModel model = (OntModel)sContext.getAttribute("jenaOntModel");
+        OntModel baseModel = (OntModel)sContext.getAttribute("baseOntModel");
+        OntModel infModel = (OntModel)sContext.getAttribute("inferenceOntModel");
+	
+        BrowseControllerChangeListener bccl = new BrowseControllerChangeListener(this);
+        model.register(bccl);
+        baseModel.register(bccl);
+        infModel.register(bccl);
+
+        _rebuildQueue.add(REBUILD_EVERY_PORTAL);
+        _cacheRebuildThread = new RebuildGroupCacheThread(this);
+        _cacheRebuildThread.setDaemon(true);
+        _cacheRebuildThread.start();
+        _cacheRebuildThread.informOfQueueChange();
+    }
+
+    public void doPost(HttpServletRequest request, HttpServletResponse response)
+    throws ServletException,IOException {
+        doGet(request, response);
+    }
+
+    /**
+     * @author bdc34 adapted by jc55
+     */
+    public void doGet( HttpServletRequest request, HttpServletResponse response )
+    throws IOException, ServletException {
+        try {
+            //call doGet of super-class (that would be VitroHttpServlet).
+            super.doGet(request, response);
+            VitroRequest vreq = new VitroRequest(request);
+
+            if( vreq.getParameter("clearcache") != null ) //mainly for debugging
+                clearGroupCache();
+
+            PortalFlag portalState= vreq.getPortalFlag();
+
+            List groups = getGroups(vreq.getWebappDaoFactory().getVClassGroupDao(), vreq.getPortal().getPortalId());
+            if( groups == null || groups.isEmpty() )
+            	request.setAttribute("classgroupsIsEmpty", true);
+            
+            
+            // stick the data in the requestScope
+            request.setAttribute("classgroups",groups);
+            request.setAttribute("portalState",portalState);
+
+            request.setAttribute("title","Index to "+vreq.getPortal().getAppName()+" Contents");
+
+            request.setAttribute("bodyJsp",Controllers.BROWSE_GROUP_JSP);
+            //request.setAttribute("bodyJsp",Controllers.DEBUG_JSP);
+
+            //FINALLY: send off to the BASIC_JSP to get turned into HTML
+            RequestDispatcher rd = request.getRequestDispatcher(Controllers.BASIC_JSP);
+            // run directly to body for testing: RequestDispatcher rd = request.getRequestDispatcher(Controllers.BROWSE_GROUP_JSP);
+            rd.forward(request, response);
+        } catch (Throwable e) {
+            log.debug("BrowseController.doGet(): "+ e);
+            request.setAttribute("javax.servlet.jsp.jspException",e);
+            RequestDispatcher rd = request.getRequestDispatcher("/error.jsp");
+            rd.forward(request, response);
+        }
+    }
+
+    public void destroy(){
+        _cacheRebuildThread.kill();
+    }
+
+    private List getGroups( VClassGroupDao vcgDao, int portalId ){
+        List grp = _groupListMap.get(portalId);
+        if( grp == null ){
+            log.debug("needed to build vclassGroups for portal " + portalId);
+            // Get all classgroups, each populated with a list of their member vclasses
+            List groups = vcgDao.getPublicGroupsWithVClasses(ORDER_BY_DISPLAYRANK, !INCLUDE_UNINSTANTIATED); 
+
+            // now cull out the groups with no populated classes
+            //removeUnpopulatedClasses( groups);
+            vcgDao.removeUnpopulatedGroups(groups);
+
+            _groupListMap.put(portalId, groups);
+            return groups;
+        } else {
+            return grp;
+        }
+    }
+    
+    private static boolean ORDER_BY_DISPLAYRANK = true;
+    private static boolean INCLUDE_UNINSTANTIATED = true;
+
+//  private void removeUnpopulatedClasses( List<VClassGroup> groups){
+//          if( groups == null || groups.size() == 0 ) return;
+//            for( VClassGroup grp : groups ){
+//                ListIterator it = grp.listIterator();
+//                while(it.hasNext()){
+//                    VClass claz = (VClass)it.next();
+//                    if( claz.getEntityCount() < 1 )
+//                        it.remove();
+//                }
+//            }
+//    }
+
+    void requestCacheUpdate(String portalUri){
+        log.debug("requesting update for portal " + portalUri);
+        _rebuildQueue.add(portalUri);
+        _cacheRebuildThread.informOfQueueChange();
+    }
+
+    protected synchronized void refreshGroupCache() {
+       long start = System.currentTimeMillis();
+       try{
+           boolean rebuildAll = false;
+           HashSet<String> portalURIsToRebuild = new HashSet<String>();
+           String portalUri;
+           while ( null != (portalUri = _rebuildQueue.poll()) ){
+               if( portalUri.equals(REBUILD_EVERY_PORTAL)){
+                   rebuildAll = true;
+                   _rebuildQueue.clear();
+                   break;
+               }else{
+                   portalURIsToRebuild.add(portalUri);
+               }
+           }
+
+           ServletContext sContext = getServletConfig().getServletContext();
+           ApplicationBean appBean = new ApplicationBean();
+           WebappDaoFactory wdFactory = (WebappDaoFactory)sContext.getAttribute("webappDaoFactory");
+           if( wdFactory == null ){
+               log.error("Unable to rebuild cache: could not get 'webappDaoFactory' from Servletcontext");
+               return;
+           }
+
+           Collection<Portal> portals;
+           if( rebuildAll ){
+               portals = wdFactory.getPortalDao().getAllPortals();
+           }   else {
+               portals = new LinkedList<Portal>();
+               for( String uri : portalURIsToRebuild){
+                   Portal p =wdFactory.getPortalDao().getPortalByURI(uri);
+                   if( p!= null)
+                       portals.add(wdFactory.getPortalDao().getPortalByURI(uri));
+               }
+           }
+
+           for(Portal portal : portals){
+               rebuildCacheForPortal(portal,appBean,wdFactory);
+           }
+           log.info("rebuilt ClassGroup cache in " + (System.currentTimeMillis() - start) + " msec");
+       }catch (Exception ex){
+           log.error("could not rebuild cache", ex);
+       }
+    }
+
+    protected synchronized void rebuildCacheForPortalUri(String uri){
+        ServletContext sContext = getServletConfig().getServletContext();
+        WebappDaoFactory wdFactory = (WebappDaoFactory)sContext.getAttribute("webappDaoFactory");
+        if( wdFactory == null ){
+            log.error("Unable to rebuild cache: could not get 'webappDaoFactory' from Servletcontext");
+            return;
+        }
+        ApplicationBean appBean = new ApplicationBean();
+        Portal portal = wdFactory.getPortalDao().getPortalByURI(uri);
+        rebuildCacheForPortal(portal,appBean,wdFactory);
+    }
+
+    protected synchronized void rebuildCacheForPortal(Portal portal, ApplicationBean appBean, WebappDaoFactory wdFactory){
+        VitroFilters vFilters = null;
+        
+        if( portal.isFlag1Filtering() ){
+            PortalFlag pflag = new PortalFlag(portal.getPortalId());
+            if( vFilters == null)
+                vFilters = VitroFilterUtils.getFilterFromPortalFlag(pflag);
+            else
+                vFilters = vFilters.and( VitroFilterUtils.getFilterFromPortalFlag(pflag));
+        }
+        WebappDaoFactory filteringDaoFactory ;
+        if( vFilters !=null ){
+            filteringDaoFactory = new WebappDaoFactoryFiltering(wdFactory,vFilters);
+        }else{
+            filteringDaoFactory = wdFactory;
+        }
+        _groupListMap.remove(portal.getPortalId());
+        getGroups(filteringDaoFactory.getVClassGroupDao(),portal.getPortalId());
+    }
+
+    private void clearGroupCache(){
+        _groupListMap = new ConcurrentHashMap<Integer, List>();
+    }
+
+    /* ******************  Jena Model Change Listener***************************** */
+    private class BrowseControllerChangeListener extends StatementListener {
+        private BrowseController controller = null;
+        public BrowseControllerChangeListener(BrowseController controller){
+            this.controller=controller;
+        }
+
+        public void addedStatement(Statement stmt) {
+        	checkAndDoUpdate(stmt); 
+        }
+        
+        public void removedStatement(Statement stmt) {
+        	checkAndDoUpdate(stmt);     
+        }
+
+        private void checkAndDoUpdate(Statement stmt){
+            if( stmt==null ) return;
+            if( log.isDebugEnabled()){
+                log.debug("subject: " + stmt.getSubject().getURI());
+                log.debug("predicate: " + stmt.getPredicate().getURI());
+            }
+            if( RDF.type.getURI().equals( stmt.getPredicate().getURI())  ){
+                requestCacheUpdate(REBUILD_EVERY_PORTAL);
+            } else if( VitroVocabulary.PORTAL_FLAG1FILTERING.equals( stmt.getPredicate().getURI())){
+                requestCacheUpdate(stmt.getSubject().getURI());
+            } else if( VitroVocabulary.IN_CLASSGROUP.equals( stmt.getPredicate().getURI() )){
+                requestCacheUpdate(REBUILD_EVERY_PORTAL);
+            }
+        }
+    }
+    /* ******************** RebuildGroupCacheThread **************** */
+    protected class RebuildGroupCacheThread extends Thread {
+        BrowseController controller;
+        boolean die = false;
+        boolean queueChange = false;
+        long queueChangeMills = 0;
+        private boolean awareOfQueueChange = false;
+
+        RebuildGroupCacheThread(BrowseController controller) {
+            this.controller = controller;
+        }
+        public void run() {
+            while(true){
+                try{
+                    synchronized (this){
+                        if( _rebuildQueue.isEmpty() ){
+                             log.debug("rebuildGroupCacheThread.run() -- queye empty, sleep");
+                             wait(1000 * 60 );
+                        }
+                        if( die ) {
+                            log.debug("doing rebuildGroupCacheThread.run() -- die()");
+                            return;
+                        }
+                        if( queueChange && !awareOfQueueChange){
+                            log.debug("rebuildGroupCacheThread.run() -- awareOfQueueChange, delay start of rebuild");
+                            awareOfQueueChange = true;
+                            wait(200);
+                        }
+                    }
+
+                    if( awareOfQueueChange && System.currentTimeMillis() - queueChangeMills > 200){
+                        log.debug("rebuildGroupCacheThread.run() -- refreshGroupCache()");
+                        controller.refreshGroupCache();
+                        synchronized( this){
+                            queueChange = false;
+                        }
+                        awareOfQueueChange = false;
+                    }else {
+                        synchronized( this ){
+                            wait(200);
+                        }
+                    }
+                }   catch(InterruptedException e){}
+            }
+
+
+        }
+
+        synchronized void informOfQueueChange(){
+            queueChange = true;
+            queueChangeMills = System.currentTimeMillis();
+            this.notifyAll();
+        }
+
+        synchronized void kill(){
+            die = true;
+            notifyAll();
+        }
+    }
+
+    protected static String REBUILD_EVERY_PORTAL ="Rebuild every portal.";
+}
diff --git a/webapp/src/edu/cornell/mannlib/vitro/webapp/controller/BrowseControllerJsp.java b/webapp/src/edu/cornell/mannlib/vitro/webapp/controller/BrowseControllerJsp.java
new file mode 100644
index 000000000..47b85beaf
--- /dev/null
+++ b/webapp/src/edu/cornell/mannlib/vitro/webapp/controller/BrowseControllerJsp.java
@@ -0,0 +1,329 @@
+/* $This file is distributed under the terms of the license in /doc/license.txt$ */
+
+package edu.cornell.mannlib.vitro.webapp.controller;
+
+import com.hp.hpl.jena.ontology.OntModel;
+import com.hp.hpl.jena.rdf.listeners.StatementListener;
+import com.hp.hpl.jena.rdf.model.Statement;
+import com.hp.hpl.jena.vocabulary.RDF;
+import edu.cornell.mannlib.vitro.webapp.beans.ApplicationBean;
+import edu.cornell.mannlib.vitro.webapp.beans.Portal;
+import edu.cornell.mannlib.vitro.webapp.beans.VClass;
+import edu.cornell.mannlib.vitro.webapp.beans.VClassGroup;
+import edu.cornell.mannlib.vitro.webapp.dao.VClassGroupDao;
+import edu.cornell.mannlib.vitro.webapp.dao.VitroVocabulary;
+import edu.cornell.mannlib.vitro.webapp.dao.WebappDaoFactory;
+import edu.cornell.mannlib.vitro.webapp.dao.filtering.WebappDaoFactoryFiltering;
+import edu.cornell.mannlib.vitro.webapp.dao.filtering.filters.VitroFilterUtils;
+import edu.cornell.mannlib.vitro.webapp.dao.filtering.filters.VitroFilters;
+import edu.cornell.mannlib.vitro.webapp.flags.PortalFlag;
+import org.apache.commons.logging.Log;
+import org.apache.commons.logging.LogFactory;
+import org.joda.time.DateTime;
+
+import javax.servlet.RequestDispatcher;
+import javax.servlet.ServletContext;
+import javax.servlet.ServletException;
+import javax.servlet.http.HttpServletRequest;
+import javax.servlet.http.HttpServletResponse;
+import java.io.IOException;
+import java.util.*;
+import java.util.concurrent.ConcurrentHashMap;
+import java.util.concurrent.ConcurrentLinkedQueue;
+
+
+public class BrowseControllerJsp extends BrowseController {
+    static final long serialVersionUID=2006030721126L;
+
+    private transient ConcurrentHashMap<Integer, List> _groupListMap
+            = new ConcurrentHashMap<Integer, List>();
+    private transient ConcurrentLinkedQueue<String> _rebuildQueue
+            = new ConcurrentLinkedQueue<String>();
+    private RebuildGroupCacheThread _cacheRebuildThread;
+
+    private static final Log log = LogFactory.getLog(BrowseController.class.getName());
+
+    public void init(javax.servlet.ServletConfig servletConfig)
+            throws javax.servlet.ServletException {
+        super.init(servletConfig);
+        ServletContext sContext = servletConfig.getServletContext();
+
+        //BJL23: I'll work on a strategy for avoiding all this craziness.
+        OntModel model = (OntModel)sContext.getAttribute("jenaOntModel");
+        OntModel baseModel = (OntModel)sContext.getAttribute("baseOntModel");
+        OntModel infModel = (OntModel)sContext.getAttribute("inferenceOntModel");
+	
+        BrowseControllerChangeListener bccl = new BrowseControllerChangeListener(this);
+        model.register(bccl);
+        baseModel.register(bccl);
+        infModel.register(bccl);
+
+        _rebuildQueue.add(REBUILD_EVERY_PORTAL);
+        _cacheRebuildThread = new RebuildGroupCacheThread(this);
+        _cacheRebuildThread.setDaemon(true);
+        _cacheRebuildThread.start();
+        _cacheRebuildThread.informOfQueueChange();
+    }
+
+    public void doPost(HttpServletRequest request, HttpServletResponse response)
+    throws ServletException,IOException {
+        doGet(request, response);
+    }
+
+    /**
+     * @author bdc34 adapted by jc55
+     */
+    public void doGet( HttpServletRequest request, HttpServletResponse response )
+    throws IOException, ServletException {
+        try {
+            //call doGet of super-class (that would be VitroHttpServlet).
+            super.doGet(request, response);
+            VitroRequest vreq = new VitroRequest(request);
+
+            if( vreq.getParameter("clearcache") != null ) //mainly for debugging
+                clearGroupCache();
+
+            PortalFlag portalState= vreq.getPortalFlag();
+
+            List groups = getGroups(vreq.getWebappDaoFactory().getVClassGroupDao(), vreq.getPortal().getPortalId());
+            if( groups == null || groups.isEmpty() )
+            	request.setAttribute("classgroupsIsEmpty", true);
+            
+            
+            // stick the data in the requestScope
+            request.setAttribute("classgroups",groups);
+            request.setAttribute("portalState",portalState);
+
+            request.setAttribute("title","Index to "+vreq.getPortal().getAppName()+" Contents");
+
+            request.setAttribute("bodyJsp",Controllers.BROWSE_GROUP_JSP);
+            //request.setAttribute("bodyJsp",Controllers.DEBUG_JSP);
+
+            //FINALLY: send off to the BASIC_JSP to get turned into HTML
+            RequestDispatcher rd = request.getRequestDispatcher(Controllers.BASIC_JSP);
+            // run directly to body for testing: RequestDispatcher rd = request.getRequestDispatcher(Controllers.BROWSE_GROUP_JSP);
+            rd.forward(request, response);
+        } catch (Throwable e) {
+            log.debug("BrowseController.doGet(): "+ e);
+            request.setAttribute("javax.servlet.jsp.jspException",e);
+            RequestDispatcher rd = request.getRequestDispatcher("/error.jsp");
+            rd.forward(request, response);
+        }
+    }
+
+    public void destroy(){
+        _cacheRebuildThread.kill();
+    }
+
+    private List getGroups( VClassGroupDao vcgDao, int portalId ){
+        List grp = _groupListMap.get(portalId);
+        if( grp == null ){
+            log.debug("needed to build vclassGroups for portal " + portalId);
+            // Get all classgroups, each populated with a list of their member vclasses
+            List groups = vcgDao.getPublicGroupsWithVClasses(ORDER_BY_DISPLAYRANK, !INCLUDE_UNINSTANTIATED); 
+
+            // now cull out the groups with no populated classes
+            //removeUnpopulatedClasses( groups);
+            vcgDao.removeUnpopulatedGroups(groups);
+
+            _groupListMap.put(portalId, groups);
+            return groups;
+        } else {
+            return grp;
+        }
+    }
+    
+    private static boolean ORDER_BY_DISPLAYRANK = true;
+    private static boolean INCLUDE_UNINSTANTIATED = true;
+
+//  private void removeUnpopulatedClasses( List<VClassGroup> groups){
+//          if( groups == null || groups.size() == 0 ) return;
+//            for( VClassGroup grp : groups ){
+//                ListIterator it = grp.listIterator();
+//                while(it.hasNext()){
+//                    VClass claz = (VClass)it.next();
+//                    if( claz.getEntityCount() < 1 )
+//                        it.remove();
+//                }
+//            }
+//    }
+
+    void requestCacheUpdate(String portalUri){
+        log.debug("requesting update for portal " + portalUri);
+        _rebuildQueue.add(portalUri);
+        _cacheRebuildThread.informOfQueueChange();
+    }
+
+    protected synchronized void refreshGroupCache() {
+       long start = System.currentTimeMillis();
+       try{
+           boolean rebuildAll = false;
+           HashSet<String> portalURIsToRebuild = new HashSet<String>();
+           String portalUri;
+           while ( null != (portalUri = _rebuildQueue.poll()) ){
+               if( portalUri.equals(REBUILD_EVERY_PORTAL)){
+                   rebuildAll = true;
+                   _rebuildQueue.clear();
+                   break;
+               }else{
+                   portalURIsToRebuild.add(portalUri);
+               }
+           }
+
+           ServletContext sContext = getServletConfig().getServletContext();
+           ApplicationBean appBean = new ApplicationBean();
+           WebappDaoFactory wdFactory = (WebappDaoFactory)sContext.getAttribute("webappDaoFactory");
+           if( wdFactory == null ){
+               log.error("Unable to rebuild cache: could not get 'webappDaoFactory' from Servletcontext");
+               return;
+           }
+
+           Collection<Portal> portals;
+           if( rebuildAll ){
+               portals = wdFactory.getPortalDao().getAllPortals();
+           }   else {
+               portals = new LinkedList<Portal>();
+               for( String uri : portalURIsToRebuild){
+                   Portal p =wdFactory.getPortalDao().getPortalByURI(uri);
+                   if( p!= null)
+                       portals.add(wdFactory.getPortalDao().getPortalByURI(uri));
+               }
+           }
+
+           for(Portal portal : portals){
+               rebuildCacheForPortal(portal,appBean,wdFactory);
+           }
+           log.info("rebuilt ClassGroup cache in " + (System.currentTimeMillis() - start) + " msec");
+       }catch (Exception ex){
+           log.error("could not rebuild cache", ex);
+       }
+    }
+
+    protected synchronized void rebuildCacheForPortalUri(String uri){
+        ServletContext sContext = getServletConfig().getServletContext();
+        WebappDaoFactory wdFactory = (WebappDaoFactory)sContext.getAttribute("webappDaoFactory");
+        if( wdFactory == null ){
+            log.error("Unable to rebuild cache: could not get 'webappDaoFactory' from Servletcontext");
+            return;
+        }
+        ApplicationBean appBean = new ApplicationBean();
+        Portal portal = wdFactory.getPortalDao().getPortalByURI(uri);
+        rebuildCacheForPortal(portal,appBean,wdFactory);
+    }
+
+    protected synchronized void rebuildCacheForPortal(Portal portal, ApplicationBean appBean, WebappDaoFactory wdFactory){
+        VitroFilters vFilters = null;
+        
+        if( portal.isFlag1Filtering() ){
+            PortalFlag pflag = new PortalFlag(portal.getPortalId());
+            if( vFilters == null)
+                vFilters = VitroFilterUtils.getFilterFromPortalFlag(pflag);
+            else
+                vFilters = vFilters.and( VitroFilterUtils.getFilterFromPortalFlag(pflag));
+        }
+        WebappDaoFactory filteringDaoFactory ;
+        if( vFilters !=null ){
+            filteringDaoFactory = new WebappDaoFactoryFiltering(wdFactory,vFilters);
+        }else{
+            filteringDaoFactory = wdFactory;
+        }
+        _groupListMap.remove(portal.getPortalId());
+        getGroups(filteringDaoFactory.getVClassGroupDao(),portal.getPortalId());
+    }
+
+    private void clearGroupCache(){
+        _groupListMap = new ConcurrentHashMap<Integer, List>();
+    }
+
+    /* ******************  Jena Model Change Listener***************************** */
+    private class BrowseControllerChangeListener extends StatementListener {
+        private BrowseController controller = null;
+        public BrowseControllerChangeListener(BrowseController controller){
+            this.controller=controller;
+        }
+
+        public void addedStatement(Statement stmt) {
+        	checkAndDoUpdate(stmt); 
+        }
+        
+        public void removedStatement(Statement stmt) {
+        	checkAndDoUpdate(stmt);     
+        }
+
+        private void checkAndDoUpdate(Statement stmt){
+            if( stmt==null ) return;
+            if( log.isDebugEnabled()){
+                log.debug("subject: " + stmt.getSubject().getURI());
+                log.debug("predicate: " + stmt.getPredicate().getURI());
+            }
+            if( RDF.type.getURI().equals( stmt.getPredicate().getURI())  ){
+                requestCacheUpdate(REBUILD_EVERY_PORTAL);
+            } else if( VitroVocabulary.PORTAL_FLAG1FILTERING.equals( stmt.getPredicate().getURI())){
+                requestCacheUpdate(stmt.getSubject().getURI());
+            } else if( VitroVocabulary.IN_CLASSGROUP.equals( stmt.getPredicate().getURI() )){
+                requestCacheUpdate(REBUILD_EVERY_PORTAL);
+            }
+        }
+    }
+    /* ******************** RebuildGroupCacheThread **************** */
+    protected class RebuildGroupCacheThread extends Thread {
+        BrowseController controller;
+        boolean die = false;
+        boolean queueChange = false;
+        long queueChangeMills = 0;
+        private boolean awareOfQueueChange = false;
+
+        RebuildGroupCacheThread(BrowseController controller) {
+            this.controller = controller;
+        }
+        public void run() {
+            while(true){
+                try{
+                    synchronized (this){
+                        if( _rebuildQueue.isEmpty() ){
+                             log.debug("rebuildGroupCacheThread.run() -- queye empty, sleep");
+                             wait(1000 * 60 );
+                        }
+                        if( die ) {
+                            log.debug("doing rebuildGroupCacheThread.run() -- die()");
+                            return;
+                        }
+                        if( queueChange && !awareOfQueueChange){
+                            log.debug("rebuildGroupCacheThread.run() -- awareOfQueueChange, delay start of rebuild");
+                            awareOfQueueChange = true;
+                            wait(200);
+                        }
+                    }
+
+                    if( awareOfQueueChange && System.currentTimeMillis() - queueChangeMills > 200){
+                        log.debug("rebuildGroupCacheThread.run() -- refreshGroupCache()");
+                        controller.refreshGroupCache();
+                        synchronized( this){
+                            queueChange = false;
+                        }
+                        awareOfQueueChange = false;
+                    }else {
+                        synchronized( this ){
+                            wait(200);
+                        }
+                    }
+                }   catch(InterruptedException e){}
+            }
+
+
+        }
+
+        synchronized void informOfQueueChange(){
+            queueChange = true;
+            queueChangeMills = System.currentTimeMillis();
+            this.notifyAll();
+        }
+
+        synchronized void kill(){
+            die = true;
+            notifyAll();
+        }
+    }
+
+    protected static String REBUILD_EVERY_PORTAL ="Rebuild every portal.";
+}
diff --git a/webapp/src/edu/cornell/mannlib/vitro/webapp/controller/BrowseControllerStringTemplate.java b/webapp/src/edu/cornell/mannlib/vitro/webapp/controller/BrowseControllerStringTemplate.java
new file mode 100644
index 000000000..946ed7672
--- /dev/null
+++ b/webapp/src/edu/cornell/mannlib/vitro/webapp/controller/BrowseControllerStringTemplate.java
@@ -0,0 +1,329 @@
+/* $This file is distributed under the terms of the license in /doc/license.txt$ */
+
+package edu.cornell.mannlib.vitro.webapp.controller;
+
+import com.hp.hpl.jena.ontology.OntModel;
+import com.hp.hpl.jena.rdf.listeners.StatementListener;
+import com.hp.hpl.jena.rdf.model.Statement;
+import com.hp.hpl.jena.vocabulary.RDF;
+import edu.cornell.mannlib.vitro.webapp.beans.ApplicationBean;
+import edu.cornell.mannlib.vitro.webapp.beans.Portal;
+import edu.cornell.mannlib.vitro.webapp.beans.VClass;
+import edu.cornell.mannlib.vitro.webapp.beans.VClassGroup;
+import edu.cornell.mannlib.vitro.webapp.dao.VClassGroupDao;
+import edu.cornell.mannlib.vitro.webapp.dao.VitroVocabulary;
+import edu.cornell.mannlib.vitro.webapp.dao.WebappDaoFactory;
+import edu.cornell.mannlib.vitro.webapp.dao.filtering.WebappDaoFactoryFiltering;
+import edu.cornell.mannlib.vitro.webapp.dao.filtering.filters.VitroFilterUtils;
+import edu.cornell.mannlib.vitro.webapp.dao.filtering.filters.VitroFilters;
+import edu.cornell.mannlib.vitro.webapp.flags.PortalFlag;
+import org.apache.commons.logging.Log;
+import org.apache.commons.logging.LogFactory;
+import org.joda.time.DateTime;
+
+import javax.servlet.RequestDispatcher;
+import javax.servlet.ServletContext;
+import javax.servlet.ServletException;
+import javax.servlet.http.HttpServletRequest;
+import javax.servlet.http.HttpServletResponse;
+import java.io.IOException;
+import java.util.*;
+import java.util.concurrent.ConcurrentHashMap;
+import java.util.concurrent.ConcurrentLinkedQueue;
+
+
+public class BrowseControllerStringTemplate extends BrowseController {
+    static final long serialVersionUID=2006030721126L;
+
+    private transient ConcurrentHashMap<Integer, List> _groupListMap
+            = new ConcurrentHashMap<Integer, List>();
+    private transient ConcurrentLinkedQueue<String> _rebuildQueue
+            = new ConcurrentLinkedQueue<String>();
+    private RebuildGroupCacheThread _cacheRebuildThread;
+
+    private static final Log log = LogFactory.getLog(BrowseController.class.getName());
+
+    public void init(javax.servlet.ServletConfig servletConfig)
+            throws javax.servlet.ServletException {
+        super.init(servletConfig);
+        ServletContext sContext = servletConfig.getServletContext();
+
+        //BJL23: I'll work on a strategy for avoiding all this craziness.
+        OntModel model = (OntModel)sContext.getAttribute("jenaOntModel");
+        OntModel baseModel = (OntModel)sContext.getAttribute("baseOntModel");
+        OntModel infModel = (OntModel)sContext.getAttribute("inferenceOntModel");
+	
+        BrowseControllerChangeListener bccl = new BrowseControllerChangeListener(this);
+        model.register(bccl);
+        baseModel.register(bccl);
+        infModel.register(bccl);
+
+        _rebuildQueue.add(REBUILD_EVERY_PORTAL);
+        _cacheRebuildThread = new RebuildGroupCacheThread(this);
+        _cacheRebuildThread.setDaemon(true);
+        _cacheRebuildThread.start();
+        _cacheRebuildThread.informOfQueueChange();
+    }
+
+    public void doPost(HttpServletRequest request, HttpServletResponse response)
+    throws ServletException,IOException {
+        doGet(request, response);
+    }
+
+    /**
+     * @author bdc34 adapted by jc55
+     */
+    public void doGet( HttpServletRequest request, HttpServletResponse response )
+    throws IOException, ServletException {
+        try {
+            //call doGet of super-class (that would be VitroHttpServlet).
+            super.doGet(request, response);
+            VitroRequest vreq = new VitroRequest(request);
+
+            if( vreq.getParameter("clearcache") != null ) //mainly for debugging
+                clearGroupCache();
+
+            PortalFlag portalState= vreq.getPortalFlag();
+
+            List groups = getGroups(vreq.getWebappDaoFactory().getVClassGroupDao(), vreq.getPortal().getPortalId());
+            if( groups == null || groups.isEmpty() )
+            	request.setAttribute("classgroupsIsEmpty", true);
+            
+            
+            // stick the data in the requestScope
+            request.setAttribute("classgroups",groups);
+            request.setAttribute("portalState",portalState);
+
+            request.setAttribute("title","Index to "+vreq.getPortal().getAppName()+" Contents");
+
+            request.setAttribute("bodyJsp",Controllers.BROWSE_GROUP_JSP);
+            //request.setAttribute("bodyJsp",Controllers.DEBUG_JSP);
+
+            //FINALLY: send off to the BASIC_JSP to get turned into HTML
+            RequestDispatcher rd = request.getRequestDispatcher(Controllers.BASIC_JSP);
+            // run directly to body for testing: RequestDispatcher rd = request.getRequestDispatcher(Controllers.BROWSE_GROUP_JSP);
+            rd.forward(request, response);
+        } catch (Throwable e) {
+            log.debug("BrowseController.doGet(): "+ e);
+            request.setAttribute("javax.servlet.jsp.jspException",e);
+            RequestDispatcher rd = request.getRequestDispatcher("/error.jsp");
+            rd.forward(request, response);
+        }
+    }
+
+    public void destroy(){
+        _cacheRebuildThread.kill();
+    }
+
+    private List getGroups( VClassGroupDao vcgDao, int portalId ){
+        List grp = _groupListMap.get(portalId);
+        if( grp == null ){
+            log.debug("needed to build vclassGroups for portal " + portalId);
+            // Get all classgroups, each populated with a list of their member vclasses
+            List groups = vcgDao.getPublicGroupsWithVClasses(ORDER_BY_DISPLAYRANK, !INCLUDE_UNINSTANTIATED); 
+
+            // now cull out the groups with no populated classes
+            //removeUnpopulatedClasses( groups);
+            vcgDao.removeUnpopulatedGroups(groups);
+
+            _groupListMap.put(portalId, groups);
+            return groups;
+        } else {
+            return grp;
+        }
+    }
+    
+    private static boolean ORDER_BY_DISPLAYRANK = true;
+    private static boolean INCLUDE_UNINSTANTIATED = true;
+
+//  private void removeUnpopulatedClasses( List<VClassGroup> groups){
+//          if( groups == null || groups.size() == 0 ) return;
+//            for( VClassGroup grp : groups ){
+//                ListIterator it = grp.listIterator();
+//                while(it.hasNext()){
+//                    VClass claz = (VClass)it.next();
+//                    if( claz.getEntityCount() < 1 )
+//                        it.remove();
+//                }
+//            }
+//    }
+
+    void requestCacheUpdate(String portalUri){
+        log.debug("requesting update for portal " + portalUri);
+        _rebuildQueue.add(portalUri);
+        _cacheRebuildThread.informOfQueueChange();
+    }
+
+    protected synchronized void refreshGroupCache() {
+       long start = System.currentTimeMillis();
+       try{
+           boolean rebuildAll = false;
+           HashSet<String> portalURIsToRebuild = new HashSet<String>();
+           String portalUri;
+           while ( null != (portalUri = _rebuildQueue.poll()) ){
+               if( portalUri.equals(REBUILD_EVERY_PORTAL)){
+                   rebuildAll = true;
+                   _rebuildQueue.clear();
+                   break;
+               }else{
+                   portalURIsToRebuild.add(portalUri);
+               }
+           }
+
+           ServletContext sContext = getServletConfig().getServletContext();
+           ApplicationBean appBean = new ApplicationBean();
+           WebappDaoFactory wdFactory = (WebappDaoFactory)sContext.getAttribute("webappDaoFactory");
+           if( wdFactory == null ){
+               log.error("Unable to rebuild cache: could not get 'webappDaoFactory' from Servletcontext");
+               return;
+           }
+
+           Collection<Portal> portals;
+           if( rebuildAll ){
+               portals = wdFactory.getPortalDao().getAllPortals();
+           }   else {
+               portals = new LinkedList<Portal>();
+               for( String uri : portalURIsToRebuild){
+                   Portal p =wdFactory.getPortalDao().getPortalByURI(uri);
+                   if( p!= null)
+                       portals.add(wdFactory.getPortalDao().getPortalByURI(uri));
+               }
+           }
+
+           for(Portal portal : portals){
+               rebuildCacheForPortal(portal,appBean,wdFactory);
+           }
+           log.info("rebuilt ClassGroup cache in " + (System.currentTimeMillis() - start) + " msec");
+       }catch (Exception ex){
+           log.error("could not rebuild cache", ex);
+       }
+    }
+
+    protected synchronized void rebuildCacheForPortalUri(String uri){
+        ServletContext sContext = getServletConfig().getServletContext();
+        WebappDaoFactory wdFactory = (WebappDaoFactory)sContext.getAttribute("webappDaoFactory");
+        if( wdFactory == null ){
+            log.error("Unable to rebuild cache: could not get 'webappDaoFactory' from Servletcontext");
+            return;
+        }
+        ApplicationBean appBean = new ApplicationBean();
+        Portal portal = wdFactory.getPortalDao().getPortalByURI(uri);
+        rebuildCacheForPortal(portal,appBean,wdFactory);
+    }
+
+    protected synchronized void rebuildCacheForPortal(Portal portal, ApplicationBean appBean, WebappDaoFactory wdFactory){
+        VitroFilters vFilters = null;
+        
+        if( portal.isFlag1Filtering() ){
+            PortalFlag pflag = new PortalFlag(portal.getPortalId());
+            if( vFilters == null)
+                vFilters = VitroFilterUtils.getFilterFromPortalFlag(pflag);
+            else
+                vFilters = vFilters.and( VitroFilterUtils.getFilterFromPortalFlag(pflag));
+        }
+        WebappDaoFactory filteringDaoFactory ;
+        if( vFilters !=null ){
+            filteringDaoFactory = new WebappDaoFactoryFiltering(wdFactory,vFilters);
+        }else{
+            filteringDaoFactory = wdFactory;
+        }
+        _groupListMap.remove(portal.getPortalId());
+        getGroups(filteringDaoFactory.getVClassGroupDao(),portal.getPortalId());
+    }
+
+    private void clearGroupCache(){
+        _groupListMap = new ConcurrentHashMap<Integer, List>();
+    }
+
+    /* ******************  Jena Model Change Listener***************************** */
+    private class BrowseControllerChangeListener extends StatementListener {
+        private BrowseController controller = null;
+        public BrowseControllerChangeListener(BrowseController controller){
+            this.controller=controller;
+        }
+
+        public void addedStatement(Statement stmt) {
+        	checkAndDoUpdate(stmt); 
+        }
+        
+        public void removedStatement(Statement stmt) {
+        	checkAndDoUpdate(stmt);     
+        }
+
+        private void checkAndDoUpdate(Statement stmt){
+            if( stmt==null ) return;
+            if( log.isDebugEnabled()){
+                log.debug("subject: " + stmt.getSubject().getURI());
+                log.debug("predicate: " + stmt.getPredicate().getURI());
+            }
+            if( RDF.type.getURI().equals( stmt.getPredicate().getURI())  ){
+                requestCacheUpdate(REBUILD_EVERY_PORTAL);
+            } else if( VitroVocabulary.PORTAL_FLAG1FILTERING.equals( stmt.getPredicate().getURI())){
+                requestCacheUpdate(stmt.getSubject().getURI());
+            } else if( VitroVocabulary.IN_CLASSGROUP.equals( stmt.getPredicate().getURI() )){
+                requestCacheUpdate(REBUILD_EVERY_PORTAL);
+            }
+        }
+    }
+    /* ******************** RebuildGroupCacheThread **************** */
+    protected class RebuildGroupCacheThread extends Thread {
+        BrowseController controller;
+        boolean die = false;
+        boolean queueChange = false;
+        long queueChangeMills = 0;
+        private boolean awareOfQueueChange = false;
+
+        RebuildGroupCacheThread(BrowseController controller) {
+            this.controller = controller;
+        }
+        public void run() {
+            while(true){
+                try{
+                    synchronized (this){
+                        if( _rebuildQueue.isEmpty() ){
+                             log.debug("rebuildGroupCacheThread.run() -- queye empty, sleep");
+                             wait(1000 * 60 );
+                        }
+                        if( die ) {
+                            log.debug("doing rebuildGroupCacheThread.run() -- die()");
+                            return;
+                        }
+                        if( queueChange && !awareOfQueueChange){
+                            log.debug("rebuildGroupCacheThread.run() -- awareOfQueueChange, delay start of rebuild");
+                            awareOfQueueChange = true;
+                            wait(200);
+                        }
+                    }
+
+                    if( awareOfQueueChange && System.currentTimeMillis() - queueChangeMills > 200){
+                        log.debug("rebuildGroupCacheThread.run() -- refreshGroupCache()");
+                        controller.refreshGroupCache();
+                        synchronized( this){
+                            queueChange = false;
+                        }
+                        awareOfQueueChange = false;
+                    }else {
+                        synchronized( this ){
+                            wait(200);
+                        }
+                    }
+                }   catch(InterruptedException e){}
+            }
+
+
+        }
+
+        synchronized void informOfQueueChange(){
+            queueChange = true;
+            queueChangeMills = System.currentTimeMillis();
+            this.notifyAll();
+        }
+
+        synchronized void kill(){
+            die = true;
+            notifyAll();
+        }
+    }
+
+    protected static String REBUILD_EVERY_PORTAL ="Rebuild every portal.";
+}
diff --git a/webapp/src/edu/cornell/mannlib/vitro/webapp/controller/BrowseControllerVelocity.java b/webapp/src/edu/cornell/mannlib/vitro/webapp/controller/BrowseControllerVelocity.java
new file mode 100644
index 000000000..5087a59d3
--- /dev/null
+++ b/webapp/src/edu/cornell/mannlib/vitro/webapp/controller/BrowseControllerVelocity.java
@@ -0,0 +1,329 @@
+/* $This file is distributed under the terms of the license in /doc/license.txt$ */
+
+package edu.cornell.mannlib.vitro.webapp.controller;
+
+import com.hp.hpl.jena.ontology.OntModel;
+import com.hp.hpl.jena.rdf.listeners.StatementListener;
+import com.hp.hpl.jena.rdf.model.Statement;
+import com.hp.hpl.jena.vocabulary.RDF;
+import edu.cornell.mannlib.vitro.webapp.beans.ApplicationBean;
+import edu.cornell.mannlib.vitro.webapp.beans.Portal;
+import edu.cornell.mannlib.vitro.webapp.beans.VClass;
+import edu.cornell.mannlib.vitro.webapp.beans.VClassGroup;
+import edu.cornell.mannlib.vitro.webapp.dao.VClassGroupDao;
+import edu.cornell.mannlib.vitro.webapp.dao.VitroVocabulary;
+import edu.cornell.mannlib.vitro.webapp.dao.WebappDaoFactory;
+import edu.cornell.mannlib.vitro.webapp.dao.filtering.WebappDaoFactoryFiltering;
+import edu.cornell.mannlib.vitro.webapp.dao.filtering.filters.VitroFilterUtils;
+import edu.cornell.mannlib.vitro.webapp.dao.filtering.filters.VitroFilters;
+import edu.cornell.mannlib.vitro.webapp.flags.PortalFlag;
+import org.apache.commons.logging.Log;
+import org.apache.commons.logging.LogFactory;
+import org.joda.time.DateTime;
+
+import javax.servlet.RequestDispatcher;
+import javax.servlet.ServletContext;
+import javax.servlet.ServletException;
+import javax.servlet.http.HttpServletRequest;
+import javax.servlet.http.HttpServletResponse;
+import java.io.IOException;
+import java.util.*;
+import java.util.concurrent.ConcurrentHashMap;
+import java.util.concurrent.ConcurrentLinkedQueue;
+
+
+public class BrowseControllerVelocity extends BrowseController {
+    static final long serialVersionUID=2006030721126L;
+
+    private transient ConcurrentHashMap<Integer, List> _groupListMap
+            = new ConcurrentHashMap<Integer, List>();
+    private transient ConcurrentLinkedQueue<String> _rebuildQueue
+            = new ConcurrentLinkedQueue<String>();
+    private RebuildGroupCacheThread _cacheRebuildThread;
+
+    private static final Log log = LogFactory.getLog(BrowseController.class.getName());
+
+    public void init(javax.servlet.ServletConfig servletConfig)
+            throws javax.servlet.ServletException {
+        super.init(servletConfig);
+        ServletContext sContext = servletConfig.getServletContext();
+
+        //BJL23: I'll work on a strategy for avoiding all this craziness.
+        OntModel model = (OntModel)sContext.getAttribute("jenaOntModel");
+        OntModel baseModel = (OntModel)sContext.getAttribute("baseOntModel");
+        OntModel infModel = (OntModel)sContext.getAttribute("inferenceOntModel");
+	
+        BrowseControllerChangeListener bccl = new BrowseControllerChangeListener(this);
+        model.register(bccl);
+        baseModel.register(bccl);
+        infModel.register(bccl);
+
+        _rebuildQueue.add(REBUILD_EVERY_PORTAL);
+        _cacheRebuildThread = new RebuildGroupCacheThread(this);
+        _cacheRebuildThread.setDaemon(true);
+        _cacheRebuildThread.start();
+        _cacheRebuildThread.informOfQueueChange();
+    }
+
+    public void doPost(HttpServletRequest request, HttpServletResponse response)
+    throws ServletException,IOException {
+        doGet(request, response);
+    }
+
+    /**
+     * @author bdc34 adapted by jc55
+     */
+    public void doGet( HttpServletRequest request, HttpServletResponse response )
+    throws IOException, ServletException {
+        try {
+            //call doGet of super-class (that would be VitroHttpServlet).
+            super.doGet(request, response);
+            VitroRequest vreq = new VitroRequest(request);
+
+            if( vreq.getParameter("clearcache") != null ) //mainly for debugging
+                clearGroupCache();
+
+            PortalFlag portalState= vreq.getPortalFlag();
+
+            List groups = getGroups(vreq.getWebappDaoFactory().getVClassGroupDao(), vreq.getPortal().getPortalId());
+            if( groups == null || groups.isEmpty() )
+            	request.setAttribute("classgroupsIsEmpty", true);
+            
+            
+            // stick the data in the requestScope
+            request.setAttribute("classgroups",groups);
+            request.setAttribute("portalState",portalState);
+
+            request.setAttribute("title","Index to "+vreq.getPortal().getAppName()+" Contents");
+
+            request.setAttribute("bodyJsp",Controllers.BROWSE_GROUP_JSP);
+            //request.setAttribute("bodyJsp",Controllers.DEBUG_JSP);
+
+            //FINALLY: send off to the BASIC_JSP to get turned into HTML
+            RequestDispatcher rd = request.getRequestDispatcher(Controllers.BASIC_JSP);
+            // run directly to body for testing: RequestDispatcher rd = request.getRequestDispatcher(Controllers.BROWSE_GROUP_JSP);
+            rd.forward(request, response);
+        } catch (Throwable e) {
+            log.debug("BrowseController.doGet(): "+ e);
+            request.setAttribute("javax.servlet.jsp.jspException",e);
+            RequestDispatcher rd = request.getRequestDispatcher("/error.jsp");
+            rd.forward(request, response);
+        }
+    }
+
+    public void destroy(){
+        _cacheRebuildThread.kill();
+    }
+
+    private List getGroups( VClassGroupDao vcgDao, int portalId ){
+        List grp = _groupListMap.get(portalId);
+        if( grp == null ){
+            log.debug("needed to build vclassGroups for portal " + portalId);
+            // Get all classgroups, each populated with a list of their member vclasses
+            List groups = vcgDao.getPublicGroupsWithVClasses(ORDER_BY_DISPLAYRANK, !INCLUDE_UNINSTANTIATED); 
+
+            // now cull out the groups with no populated classes
+            //removeUnpopulatedClasses( groups);
+            vcgDao.removeUnpopulatedGroups(groups);
+
+            _groupListMap.put(portalId, groups);
+            return groups;
+        } else {
+            return grp;
+        }
+    }
+    
+    private static boolean ORDER_BY_DISPLAYRANK = true;
+    private static boolean INCLUDE_UNINSTANTIATED = true;
+
+//  private void removeUnpopulatedClasses( List<VClassGroup> groups){
+//          if( groups == null || groups.size() == 0 ) return;
+//            for( VClassGroup grp : groups ){
+//                ListIterator it = grp.listIterator();
+//                while(it.hasNext()){
+//                    VClass claz = (VClass)it.next();
+//                    if( claz.getEntityCount() < 1 )
+//                        it.remove();
+//                }
+//            }
+//    }
+
+    void requestCacheUpdate(String portalUri){
+        log.debug("requesting update for portal " + portalUri);
+        _rebuildQueue.add(portalUri);
+        _cacheRebuildThread.informOfQueueChange();
+    }
+
+    protected synchronized void refreshGroupCache() {
+       long start = System.currentTimeMillis();
+       try{
+           boolean rebuildAll = false;
+           HashSet<String> portalURIsToRebuild = new HashSet<String>();
+           String portalUri;
+           while ( null != (portalUri = _rebuildQueue.poll()) ){
+               if( portalUri.equals(REBUILD_EVERY_PORTAL)){
+                   rebuildAll = true;
+                   _rebuildQueue.clear();
+                   break;
+               }else{
+                   portalURIsToRebuild.add(portalUri);
+               }
+           }
+
+           ServletContext sContext = getServletConfig().getServletContext();
+           ApplicationBean appBean = new ApplicationBean();
+           WebappDaoFactory wdFactory = (WebappDaoFactory)sContext.getAttribute("webappDaoFactory");
+           if( wdFactory == null ){
+               log.error("Unable to rebuild cache: could not get 'webappDaoFactory' from Servletcontext");
+               return;
+           }
+
+           Collection<Portal> portals;
+           if( rebuildAll ){
+               portals = wdFactory.getPortalDao().getAllPortals();
+           }   else {
+               portals = new LinkedList<Portal>();
+               for( String uri : portalURIsToRebuild){
+                   Portal p =wdFactory.getPortalDao().getPortalByURI(uri);
+                   if( p!= null)
+                       portals.add(wdFactory.getPortalDao().getPortalByURI(uri));
+               }
+           }
+
+           for(Portal portal : portals){
+               rebuildCacheForPortal(portal,appBean,wdFactory);
+           }
+           log.info("rebuilt ClassGroup cache in " + (System.currentTimeMillis() - start) + " msec");
+       }catch (Exception ex){
+           log.error("could not rebuild cache", ex);
+       }
+    }
+
+    protected synchronized void rebuildCacheForPortalUri(String uri){
+        ServletContext sContext = getServletConfig().getServletContext();
+        WebappDaoFactory wdFactory = (WebappDaoFactory)sContext.getAttribute("webappDaoFactory");
+        if( wdFactory == null ){
+            log.error("Unable to rebuild cache: could not get 'webappDaoFactory' from Servletcontext");
+            return;
+        }
+        ApplicationBean appBean = new ApplicationBean();
+        Portal portal = wdFactory.getPortalDao().getPortalByURI(uri);
+        rebuildCacheForPortal(portal,appBean,wdFactory);
+    }
+
+    protected synchronized void rebuildCacheForPortal(Portal portal, ApplicationBean appBean, WebappDaoFactory wdFactory){
+        VitroFilters vFilters = null;
+        
+        if( portal.isFlag1Filtering() ){
+            PortalFlag pflag = new PortalFlag(portal.getPortalId());
+            if( vFilters == null)
+                vFilters = VitroFilterUtils.getFilterFromPortalFlag(pflag);
+            else
+                vFilters = vFilters.and( VitroFilterUtils.getFilterFromPortalFlag(pflag));
+        }
+        WebappDaoFactory filteringDaoFactory ;
+        if( vFilters !=null ){
+            filteringDaoFactory = new WebappDaoFactoryFiltering(wdFactory,vFilters);
+        }else{
+            filteringDaoFactory = wdFactory;
+        }
+        _groupListMap.remove(portal.getPortalId());
+        getGroups(filteringDaoFactory.getVClassGroupDao(),portal.getPortalId());
+    }
+
+    private void clearGroupCache(){
+        _groupListMap = new ConcurrentHashMap<Integer, List>();
+    }
+
+    /* ******************  Jena Model Change Listener***************************** */
+    private class BrowseControllerChangeListener extends StatementListener {
+        private BrowseController controller = null;
+        public BrowseControllerChangeListener(BrowseController controller){
+            this.controller=controller;
+        }
+
+        public void addedStatement(Statement stmt) {
+        	checkAndDoUpdate(stmt); 
+        }
+        
+        public void removedStatement(Statement stmt) {
+        	checkAndDoUpdate(stmt);     
+        }
+
+        private void checkAndDoUpdate(Statement stmt){
+            if( stmt==null ) return;
+            if( log.isDebugEnabled()){
+                log.debug("subject: " + stmt.getSubject().getURI());
+                log.debug("predicate: " + stmt.getPredicate().getURI());
+            }
+            if( RDF.type.getURI().equals( stmt.getPredicate().getURI())  ){
+                requestCacheUpdate(REBUILD_EVERY_PORTAL);
+            } else if( VitroVocabulary.PORTAL_FLAG1FILTERING.equals( stmt.getPredicate().getURI())){
+                requestCacheUpdate(stmt.getSubject().getURI());
+            } else if( VitroVocabulary.IN_CLASSGROUP.equals( stmt.getPredicate().getURI() )){
+                requestCacheUpdate(REBUILD_EVERY_PORTAL);
+            }
+        }
+    }
+    /* ******************** RebuildGroupCacheThread **************** */
+    protected class RebuildGroupCacheThread extends Thread {
+        BrowseController controller;
+        boolean die = false;
+        boolean queueChange = false;
+        long queueChangeMills = 0;
+        private boolean awareOfQueueChange = false;
+
+        RebuildGroupCacheThread(BrowseController controller) {
+            this.controller = controller;
+        }
+        public void run() {
+            while(true){
+                try{
+                    synchronized (this){
+                        if( _rebuildQueue.isEmpty() ){
+                             log.debug("rebuildGroupCacheThread.run() -- queye empty, sleep");
+                             wait(1000 * 60 );
+                        }
+                        if( die ) {
+                            log.debug("doing rebuildGroupCacheThread.run() -- die()");
+                            return;
+                        }
+                        if( queueChange && !awareOfQueueChange){
+                            log.debug("rebuildGroupCacheThread.run() -- awareOfQueueChange, delay start of rebuild");
+                            awareOfQueueChange = true;
+                            wait(200);
+                        }
+                    }
+
+                    if( awareOfQueueChange && System.currentTimeMillis() - queueChangeMills > 200){
+                        log.debug("rebuildGroupCacheThread.run() -- refreshGroupCache()");
+                        controller.refreshGroupCache();
+                        synchronized( this){
+                            queueChange = false;
+                        }
+                        awareOfQueueChange = false;
+                    }else {
+                        synchronized( this ){
+                            wait(200);
+                        }
+                    }
+                }   catch(InterruptedException e){}
+            }
+
+
+        }
+
+        synchronized void informOfQueueChange(){
+            queueChange = true;
+            queueChangeMills = System.currentTimeMillis();
+            this.notifyAll();
+        }
+
+        synchronized void kill(){
+            die = true;
+            notifyAll();
+        }
+    }
+
+    protected static String REBUILD_EVERY_PORTAL ="Rebuild every portal.";
+}
diff --git a/webapp/src/edu/cornell/mannlib/vitro/webapp/controller/BrowseControllerWicket.java b/webapp/src/edu/cornell/mannlib/vitro/webapp/controller/BrowseControllerWicket.java
new file mode 100644
index 000000000..cd0e1d9bc
--- /dev/null
+++ b/webapp/src/edu/cornell/mannlib/vitro/webapp/controller/BrowseControllerWicket.java
@@ -0,0 +1,329 @@
+/* $This file is distributed under the terms of the license in /doc/license.txt$ */
+
+package edu.cornell.mannlib.vitro.webapp.controller;
+
+import com.hp.hpl.jena.ontology.OntModel;
+import com.hp.hpl.jena.rdf.listeners.StatementListener;
+import com.hp.hpl.jena.rdf.model.Statement;
+import com.hp.hpl.jena.vocabulary.RDF;
+import edu.cornell.mannlib.vitro.webapp.beans.ApplicationBean;
+import edu.cornell.mannlib.vitro.webapp.beans.Portal;
+import edu.cornell.mannlib.vitro.webapp.beans.VClass;
+import edu.cornell.mannlib.vitro.webapp.beans.VClassGroup;
+import edu.cornell.mannlib.vitro.webapp.dao.VClassGroupDao;
+import edu.cornell.mannlib.vitro.webapp.dao.VitroVocabulary;
+import edu.cornell.mannlib.vitro.webapp.dao.WebappDaoFactory;
+import edu.cornell.mannlib.vitro.webapp.dao.filtering.WebappDaoFactoryFiltering;
+import edu.cornell.mannlib.vitro.webapp.dao.filtering.filters.VitroFilterUtils;
+import edu.cornell.mannlib.vitro.webapp.dao.filtering.filters.VitroFilters;
+import edu.cornell.mannlib.vitro.webapp.flags.PortalFlag;
+import org.apache.commons.logging.Log;
+import org.apache.commons.logging.LogFactory;
+import org.joda.time.DateTime;
+
+import javax.servlet.RequestDispatcher;
+import javax.servlet.ServletContext;
+import javax.servlet.ServletException;
+import javax.servlet.http.HttpServletRequest;
+import javax.servlet.http.HttpServletResponse;
+import java.io.IOException;
+import java.util.*;
+import java.util.concurrent.ConcurrentHashMap;
+import java.util.concurrent.ConcurrentLinkedQueue;
+
+
+public class BrowseControllerWicket extends BrowseController {
+    static final long serialVersionUID=2006030721126L;
+
+    private transient ConcurrentHashMap<Integer, List> _groupListMap
+            = new ConcurrentHashMap<Integer, List>();
+    private transient ConcurrentLinkedQueue<String> _rebuildQueue
+            = new ConcurrentLinkedQueue<String>();
+    private RebuildGroupCacheThread _cacheRebuildThread;
+
+    private static final Log log = LogFactory.getLog(BrowseController.class.getName());
+
+    public void init(javax.servlet.ServletConfig servletConfig)
+            throws javax.servlet.ServletException {
+        super.init(servletConfig);
+        ServletContext sContext = servletConfig.getServletContext();
+
+        //BJL23: I'll work on a strategy for avoiding all this craziness.
+        OntModel model = (OntModel)sContext.getAttribute("jenaOntModel");
+        OntModel baseModel = (OntModel)sContext.getAttribute("baseOntModel");
+        OntModel infModel = (OntModel)sContext.getAttribute("inferenceOntModel");
+	
+        BrowseControllerChangeListener bccl = new BrowseControllerChangeListener(this);
+        model.register(bccl);
+        baseModel.register(bccl);
+        infModel.register(bccl);
+
+        _rebuildQueue.add(REBUILD_EVERY_PORTAL);
+        _cacheRebuildThread = new RebuildGroupCacheThread(this);
+        _cacheRebuildThread.setDaemon(true);
+        _cacheRebuildThread.start();
+        _cacheRebuildThread.informOfQueueChange();
+    }
+
+    public void doPost(HttpServletRequest request, HttpServletResponse response)
+    throws ServletException,IOException {
+        doGet(request, response);
+    }
+
+    /**
+     * @author bdc34 adapted by jc55
+     */
+    public void doGet( HttpServletRequest request, HttpServletResponse response )
+    throws IOException, ServletException {
+        try {
+            //call doGet of super-class (that would be VitroHttpServlet).
+            super.doGet(request, response);
+            VitroRequest vreq = new VitroRequest(request);
+
+            if( vreq.getParameter("clearcache") != null ) //mainly for debugging
+                clearGroupCache();
+
+            PortalFlag portalState= vreq.getPortalFlag();
+
+            List groups = getGroups(vreq.getWebappDaoFactory().getVClassGroupDao(), vreq.getPortal().getPortalId());
+            if( groups == null || groups.isEmpty() )
+            	request.setAttribute("classgroupsIsEmpty", true);
+            
+            
+            // stick the data in the requestScope
+            request.setAttribute("classgroups",groups);
+            request.setAttribute("portalState",portalState);
+
+            request.setAttribute("title","Index to "+vreq.getPortal().getAppName()+" Contents");
+
+            request.setAttribute("bodyJsp",Controllers.BROWSE_GROUP_JSP);
+            //request.setAttribute("bodyJsp",Controllers.DEBUG_JSP);
+
+            //FINALLY: send off to the BASIC_JSP to get turned into HTML
+            RequestDispatcher rd = request.getRequestDispatcher(Controllers.BASIC_JSP);
+            // run directly to body for testing: RequestDispatcher rd = request.getRequestDispatcher(Controllers.BROWSE_GROUP_JSP);
+            rd.forward(request, response);
+        } catch (Throwable e) {
+            log.debug("BrowseController.doGet(): "+ e);
+            request.setAttribute("javax.servlet.jsp.jspException",e);
+            RequestDispatcher rd = request.getRequestDispatcher("/error.jsp");
+            rd.forward(request, response);
+        }
+    }
+
+    public void destroy(){
+        _cacheRebuildThread.kill();
+    }
+
+    private List getGroups( VClassGroupDao vcgDao, int portalId ){
+        List grp = _groupListMap.get(portalId);
+        if( grp == null ){
+            log.debug("needed to build vclassGroups for portal " + portalId);
+            // Get all classgroups, each populated with a list of their member vclasses
+            List groups = vcgDao.getPublicGroupsWithVClasses(ORDER_BY_DISPLAYRANK, !INCLUDE_UNINSTANTIATED); 
+
+            // now cull out the groups with no populated classes
+            //removeUnpopulatedClasses( groups);
+            vcgDao.removeUnpopulatedGroups(groups);
+
+            _groupListMap.put(portalId, groups);
+            return groups;
+        } else {
+            return grp;
+        }
+    }
+    
+    private static boolean ORDER_BY_DISPLAYRANK = true;
+    private static boolean INCLUDE_UNINSTANTIATED = true;
+
+//  private void removeUnpopulatedClasses( List<VClassGroup> groups){
+//          if( groups == null || groups.size() == 0 ) return;
+//            for( VClassGroup grp : groups ){
+//                ListIterator it = grp.listIterator();
+//                while(it.hasNext()){
+//                    VClass claz = (VClass)it.next();
+//                    if( claz.getEntityCount() < 1 )
+//                        it.remove();
+//                }
+//            }
+//    }
+
+    void requestCacheUpdate(String portalUri){
+        log.debug("requesting update for portal " + portalUri);
+        _rebuildQueue.add(portalUri);
+        _cacheRebuildThread.informOfQueueChange();
+    }
+
+    protected synchronized void refreshGroupCache() {
+       long start = System.currentTimeMillis();
+       try{
+           boolean rebuildAll = false;
+           HashSet<String> portalURIsToRebuild = new HashSet<String>();
+           String portalUri;
+           while ( null != (portalUri = _rebuildQueue.poll()) ){
+               if( portalUri.equals(REBUILD_EVERY_PORTAL)){
+                   rebuildAll = true;
+                   _rebuildQueue.clear();
+                   break;
+               }else{
+                   portalURIsToRebuild.add(portalUri);
+               }
+           }
+
+           ServletContext sContext = getServletConfig().getServletContext();
+           ApplicationBean appBean = new ApplicationBean();
+           WebappDaoFactory wdFactory = (WebappDaoFactory)sContext.getAttribute("webappDaoFactory");
+           if( wdFactory == null ){
+               log.error("Unable to rebuild cache: could not get 'webappDaoFactory' from Servletcontext");
+               return;
+           }
+
+           Collection<Portal> portals;
+           if( rebuildAll ){
+               portals = wdFactory.getPortalDao().getAllPortals();
+           }   else {
+               portals = new LinkedList<Portal>();
+               for( String uri : portalURIsToRebuild){
+                   Portal p =wdFactory.getPortalDao().getPortalByURI(uri);
+                   if( p!= null)
+                       portals.add(wdFactory.getPortalDao().getPortalByURI(uri));
+               }
+           }
+
+           for(Portal portal : portals){
+               rebuildCacheForPortal(portal,appBean,wdFactory);
+           }
+           log.info("rebuilt ClassGroup cache in " + (System.currentTimeMillis() - start) + " msec");
+       }catch (Exception ex){
+           log.error("could not rebuild cache", ex);
+       }
+    }
+
+    protected synchronized void rebuildCacheForPortalUri(String uri){
+        ServletContext sContext = getServletConfig().getServletContext();
+        WebappDaoFactory wdFactory = (WebappDaoFactory)sContext.getAttribute("webappDaoFactory");
+        if( wdFactory == null ){
+            log.error("Unable to rebuild cache: could not get 'webappDaoFactory' from Servletcontext");
+            return;
+        }
+        ApplicationBean appBean = new ApplicationBean();
+        Portal portal = wdFactory.getPortalDao().getPortalByURI(uri);
+        rebuildCacheForPortal(portal,appBean,wdFactory);
+    }
+
+    protected synchronized void rebuildCacheForPortal(Portal portal, ApplicationBean appBean, WebappDaoFactory wdFactory){
+        VitroFilters vFilters = null;
+        
+        if( portal.isFlag1Filtering() ){
+            PortalFlag pflag = new PortalFlag(portal.getPortalId());
+            if( vFilters == null)
+                vFilters = VitroFilterUtils.getFilterFromPortalFlag(pflag);
+            else
+                vFilters = vFilters.and( VitroFilterUtils.getFilterFromPortalFlag(pflag));
+        }
+        WebappDaoFactory filteringDaoFactory ;
+        if( vFilters !=null ){
+            filteringDaoFactory = new WebappDaoFactoryFiltering(wdFactory,vFilters);
+        }else{
+            filteringDaoFactory = wdFactory;
+        }
+        _groupListMap.remove(portal.getPortalId());
+        getGroups(filteringDaoFactory.getVClassGroupDao(),portal.getPortalId());
+    }
+
+    private void clearGroupCache(){
+        _groupListMap = new ConcurrentHashMap<Integer, List>();
+    }
+
+    /* ******************  Jena Model Change Listener***************************** */
+    private class BrowseControllerChangeListener extends StatementListener {
+        private BrowseController controller = null;
+        public BrowseControllerChangeListener(BrowseController controller){
+            this.controller=controller;
+        }
+
+        public void addedStatement(Statement stmt) {
+        	checkAndDoUpdate(stmt); 
+        }
+        
+        public void removedStatement(Statement stmt) {
+        	checkAndDoUpdate(stmt);     
+        }
+
+        private void checkAndDoUpdate(Statement stmt){
+            if( stmt==null ) return;
+            if( log.isDebugEnabled()){
+                log.debug("subject: " + stmt.getSubject().getURI());
+                log.debug("predicate: " + stmt.getPredicate().getURI());
+            }
+            if( RDF.type.getURI().equals( stmt.getPredicate().getURI())  ){
+                requestCacheUpdate(REBUILD_EVERY_PORTAL);
+            } else if( VitroVocabulary.PORTAL_FLAG1FILTERING.equals( stmt.getPredicate().getURI())){
+                requestCacheUpdate(stmt.getSubject().getURI());
+            } else if( VitroVocabulary.IN_CLASSGROUP.equals( stmt.getPredicate().getURI() )){
+                requestCacheUpdate(REBUILD_EVERY_PORTAL);
+            }
+        }
+    }
+    /* ******************** RebuildGroupCacheThread **************** */
+    protected class RebuildGroupCacheThread extends Thread {
+        BrowseController controller;
+        boolean die = false;
+        boolean queueChange = false;
+        long queueChangeMills = 0;
+        private boolean awareOfQueueChange = false;
+
+        RebuildGroupCacheThread(BrowseController controller) {
+            this.controller = controller;
+        }
+        public void run() {
+            while(true){
+                try{
+                    synchronized (this){
+                        if( _rebuildQueue.isEmpty() ){
+                             log.debug("rebuildGroupCacheThread.run() -- queye empty, sleep");
+                             wait(1000 * 60 );
+                        }
+                        if( die ) {
+                            log.debug("doing rebuildGroupCacheThread.run() -- die()");
+                            return;
+                        }
+                        if( queueChange && !awareOfQueueChange){
+                            log.debug("rebuildGroupCacheThread.run() -- awareOfQueueChange, delay start of rebuild");
+                            awareOfQueueChange = true;
+                            wait(200);
+                        }
+                    }
+
+                    if( awareOfQueueChange && System.currentTimeMillis() - queueChangeMills > 200){
+                        log.debug("rebuildGroupCacheThread.run() -- refreshGroupCache()");
+                        controller.refreshGroupCache();
+                        synchronized( this){
+                            queueChange = false;
+                        }
+                        awareOfQueueChange = false;
+                    }else {
+                        synchronized( this ){
+                            wait(200);
+                        }
+                    }
+                }   catch(InterruptedException e){}
+            }
+
+
+        }
+
+        synchronized void informOfQueueChange(){
+            queueChange = true;
+            queueChangeMills = System.currentTimeMillis();
+            this.notifyAll();
+        }
+
+        synchronized void kill(){
+            die = true;
+            notifyAll();
+        }
+    }
+
+    protected static String REBUILD_EVERY_PORTAL ="Rebuild every portal.";
+}