code: public List<EtcdNode> listDir(String key, boolean recursive) throws EtcdClientException {
          Preconditions.checkNotNull(key);
  
          Map<String, String> params = new HashMap<String, String>();
          if (recursive) {
              params.put("recursive", String.valueOf(true));
          }
  
          URI uri = buildUriWithKeyAndParams(key, params);
          HttpGet httpGet = new HttpGet(uri);
  
          EtcdResult result = syncExecute(httpGet, new int[] {200, 404}, 100);
          if (null == result || null == result.node) {
              return null;
          }
  
          return result.node.nodes;
      }
docs: Listing a directory with recursive
  @param key the dir key
  @param recursive recursive
  @return CEtcdNode list
  @throws EtcdClientException