@Path("/")
public class ContextService {
    @GET
    @Path("/forward")
    public void forward(@Context HttpRequest request) {
        request.forward("/WEB-INF/index.html");
    }

   public void forward(final ServletRequest request, final ServletResponse response) throws ServletException, IOException {
      if (System.getSecurityManager() != null) {
         try {
            AccessController.doPrivileged(new PrivilegedExceptionAction<Object>() {
               public Object run() throws Exception {
                  RequestDispatcherImpl.this.forwardImplSetup(request, response);
                  return null;
               }
            });
 ....