code: public boolean deleteShard(String shard) {
          Utils.require(!Utils.isEmpty(shard), "shard");
          try {
              // Send a DELETE request to "/{application}/_shards/{shard}"
              StringBuilder uri = new StringBuilder(Utils.isEmpty(m_restClient.getApiPrefix()) ? "" : "/" + m_restClient.getApiPrefix());          			            
              uri.append("/");
              uri.append(Utils.urlEncode(m_appDef.getAppName()));
              uri.append("/_shards/");
              uri.append(Utils.urlEncode(shard));
              RESTResponse response = m_restClient.sendRequest(HttpMethod.DELETE, uri.toString());
              m_logger.debug("deleteShard() response: {}", response.toString());
              throwIfErrorResponse(response);
              return true;
          } catch (Exception e) {
              throw new RuntimeException(e);
          }
      }
docs: Delete the OLAP shard with the given name belonging to this session's application.
  True is returned if the delete was successful. An exception is thrown if an error
  occurred.
  
  @param shard     Shard name.
  @return          True if the shard was successfully deleted.