How can I implement request and response filters in Business Workflow Automation Case plug-ins?

public class RequestFilter extends PluginRequestFilter {
               /**
               * Returns the names of the services that are extended by this filter.
               *
                * @return A <code>String</code> array that contains the names of the services.
               */
               public String[] getFilteredServices() {
                              return new String[] { "/p8/getWorkItems", "/p8/getNextWorkItems" };
               }

public class FilterTest extends PluginResponseFilter {

               /**
               * Returns an array of the services that are extended by this filter.
               *
                * @return A <code>String</code> array of names of the services. These are
               *         the servlet paths or Struts action names.
               */
               public String[] getFilteredServices() {
                              return new String[] { "/p8/getWorkItems", "/p8/getNextWorkItems"};
               }

JSONObject result = onExecute(domain, objStore, repositoryId, resourceRequest);
logger.logDebug(this, methodName,"Result JSON: "+result.toString());
JSONResponse jsr = new JSONResponse();
Iterator resultit = result.entrySet().iterator();
while (resultit.hasNext()) {
   Map.Entry pairs = (Map.Entry)resultit.next();
   jsr.put(pairs.getKey(), pairs.getValue() );
}
PluginResponseUtil.writeJSONResponse(request, response, jsr, callbacks, getId());