code: @Override
      public Set<Entry<String, GroovyRunner>> entrySet() {
          Map<String, GroovyRunner> map = getMap();
          readLock.lock();
          try {
              if (map.isEmpty()) {
                  return Collections.emptySet();
              }
              return Collections.unmodifiableSet(new LinkedHashSet<>(map.entrySet()));
          } finally {
              readLock.unlock();
          }
      }
docs: Returns a set of entries for registered runners.
  This is a snapshot of the registry and any subsequent
  registry changes will not be reflected in the set.
  
  @return an unmodifiable set of registered runner entries