/** Binds the specified {@link Service} at the specified exact path. */
 protected T serviceAt(String exactPath, Service service) {
   return service(CompositeServiceEntry.ofExact(exactPath, service));
 }
 /** Binds the specified {@link Service} under the specified directory.. */
 protected T serviceUnder(String pathPrefix, Service service) {
   return service(CompositeServiceEntry.ofPrefix(pathPrefix, service));
 }
 /** Binds the specified {@link Service} at the specified {@link PathMapping}. */
 protected T service(PathMapping pathMapping, Service service) {
   return service(CompositeServiceEntry.of(pathMapping, service));
 }