code: protected Component createContentPane() {
          JPanel content = new JPanel(new BorderLayout());
          Component component = super.createContentPane();
          if(component != null)
              content.add(component);
  
          JProgressBar progressBar = getProgressBar();
          progressBar.setIndeterminate(isIndeterminate());
          progressBar.setStringPainted(isShowProgressLabel());
  
          content.add(progressBar, BorderLayout.SOUTH);
  
          return content;
      }
docs: Returns a component that displays an image above a progress bar.
  
  @return A splash screen containing an image and a progress bar, never null.