Java Swing - 如何当文本超过窗口宽度时添加JScrollbar

import javax.swing.JFrame;
import javax.swing.JScrollPane;
import javax.swing.JTextPane;

public class Main extends JFrame {
  public Main() {
    JScrollPane scrollPane = new JScrollPane();
    JTextPane textPane = new JTextPane();

    scrollPane.setViewportView(textPane);
    add(scrollPane);

    setTitle("Main");
    setSize(300, 300);
    setDefaultCloseOperation(EXIT_ON_CLOSE);
    setVisible(true);
  }

  public static void main(String[] args) {
    new Main();
  }
}