code: public FleetResponse getFleetsFleetId(Long fleetId, String datasource, String ifNoneMatch, String token)
              throws ApiException {
          ApiResponse<FleetResponse> resp = getFleetsFleetIdWithHttpInfo(fleetId, datasource, ifNoneMatch, token);
          return resp.getData();
      }
docs: Get fleet information Return details about a fleet --- This route is
  cached for up to 5 seconds SSO Scope: esi-fleets.read_fleet.v1
  
  @param fleetId
  ID for a fleet (required)
  @param datasource
  The server name you would like data from (optional, default to
  tranquility)
  @param ifNoneMatch
  ETag from a previous request. A 304 will be returned if this
  matches the current ETag (optional)
  @param token
  Access token to use if unable to set a header (optional)
  @return FleetResponse
  @throws ApiException
  If fail to call the API, e.g. server error or cannot
  deserialize the response body