docs: private Map<String, GroovyRunner> getMap() {
          Map<String, GroovyRunner> map = runnerMap;
          if (map == null) {
              writeLock.lock();
              try {
                  if ((map = runnerMap) == null) {
                      runnerMap = map = new LinkedHashMap<>();
                      load(null);
                  }
              } finally {
                  writeLock.unlock();
              }
          }
          return map;
      }