code: @Override
      public final void start(final Stage primaryStage) throws Exception {
          Assert.requireNonNull(primaryStage, "primaryStage");
  
          this.primaryStage = primaryStage;
  
          if (initializationException == null) {
              if (clientContext != null) {
                  try {
                      start(primaryStage, clientContext);
                  } catch (Exception e) {
                      handleInitializationError(primaryStage, new ClientInitializationException("Error in application start!", e));
                  }
              } else {
                  handleInitializationError(primaryStage, new ClientInitializationException("No clientContext was created!"));
              }
          } else {
              handleInitializationError(primaryStage, initializationException);
          }
      }
docs: This methods defines parts of the Dolphin Platform lifecyycle and is therefore defined as final.
  Use the {@link DolphinPlatformApplication#start(Stage, ClientContext)} method instead.
  
  @param primaryStage the primary stage
  @throws Exception in case of an error