Java Swing - 如何确定是否在JOptionPane中单击OK

import javax.swing.Box;
import javax.swing.JLabel;
import javax.swing.JOptionPane;
import javax.swing.JPanel;
import javax.swing.JTextField;

public class Main {
  public static void main(String[] args) {
    JTextField ipField = new JTextField(10);
    JTextField portField = new JTextField(10);
    JPanel panel = new JPanel();
    panel.add(new JLabel("IP:"));
    panel.add(ipField);

    panel.add(Box.createHorizontalStrut(15));
    panel.add(new JLabel("Port:"));
    panel.add(portField);

    int result = JOptionPane.showConfirmDialog(null, panel,
        "Enter Information", JOptionPane.OK_CANCEL_OPTION);

    if (result == JOptionPane.OK_OPTION) {
      System.out.println("IP: " + ipField.getText());
      System.out.println("Port: " + portField.getText());
    }
  }
}