code: public com.squareup.okhttp.Call getRouteOriginDestinationAsync(Integer destination, Integer origin,
              List<Integer> avoid, List<List<Integer>> connections, String datasource, String flag, String ifNoneMatch,
              final ApiCallback<List<Integer>> callback) throws ApiException {
  
          com.squareup.okhttp.Call call = getRouteOriginDestinationValidateBeforeCall(destination, origin, avoid,
                  connections, datasource, flag, ifNoneMatch, callback);
          Type localVarReturnType = new TypeToken<List<Integer>>() {
          }.getType();
          apiClient.executeAsync(call, localVarReturnType, callback);
          return call;
      }
docs: Get route (asynchronously) Get the systems between origin and destination
  --- This route is cached for up to 86400 seconds
  
  @param destination
  destination solar system ID (required)
  @param origin
  origin solar system ID (required)
  @param avoid
  avoid solar system ID(s) (optional)
  @param connections
  connected solar system pairs (optional)
  @param datasource
  The server name you would like data from (optional, default to
  tranquility)
  @param flag
  route security preference (optional, default to shortest)
  @param ifNoneMatch
  ETag from a previous request. A 304 will be returned if this
  matches the current ETag (optional)
  @param callback
  The callback to be executed when the API call finishes
  @return The request call
  @throws ApiException
  If fail to process the API call, e.g. serializing the request
  body object