How to add hyperlink in JLabel?

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What is the best way to add a hyperlink in a JLabel? I can get the view using html tags, but how to open the browser when the user clicks on it?

12 Answers

You can do this using a JLabel, but an alternative would be to style a JButton. That way, you don't have to worry about accessibility and can just fire events using an ActionListener.

  public static void main(String[] args) throws URISyntaxException {
    final URI uri = new URI("http://java.sun.com");
    class OpenUrlAction implements ActionListener {
      @Override public void actionPerformed(ActionEvent e) {
        open(uri);
      }
    }
    JFrame frame = new JFrame("Links");
    frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
    frame.setSize(100, 400);
    Container container = frame.getContentPane();
    container.setLayout(new GridBagLayout());
    JButton button = new JButton();
    button.setText("<HTML>Click the <FONT color=\"#000099\"><U>link</U></FONT>"
        + " to go to the Java website.</HTML>");
    button.setHorizontalAlignment(SwingConstants.LEFT);
    button.setBorderPainted(false);
    button.setOpaque(false);
    button.setBackground(Color.WHITE);
    button.setToolTipText(uri.toString());
    button.addActionListener(new OpenUrlAction());
    container.add(button);
    frame.setVisible(true);
  }

  private static void open(URI uri) {
    if (Desktop.isDesktopSupported()) {
      try {
        Desktop.getDesktop().browse(uri);
      } catch (IOException e) { /* TODO: error handling */ }
    } else { /* TODO: error handling */ }
  }

Update I've tidied up the SwingLink class further and added more features; an up-to-date copy of it can be found here: https://bitbucket.org/dimo414/jgrep/src/tip/src/grep/SwingLink.java


@McDowell's answer is great, but there's several things that could be improved upon. Notably text other than the hyperlink is clickable and it still looks like a button even though some of the styling has been changed/hidden. While accessibility is important, a coherent UI is as well.

So I put together a class extending JLabel based on McDowell's code. It's self-contained, handles errors properly, and feels more like a link:

public class SwingLink extends JLabel {
  private static final long serialVersionUID = 8273875024682878518L;
  private String text;
  private URI uri;

  public SwingLink(String text, URI uri){
    super();
    setup(text,uri);
  }

  public SwingLink(String text, String uri){
    super();
    setup(text,URI.create(uri));
  }

  public void setup(String t, URI u){
    text = t;
    uri = u;
    setText(text);
    setToolTipText(uri.toString());
    addMouseListener(new MouseAdapter() {
      public void mouseClicked(MouseEvent e) {
        open(uri);
      }
      public void mouseEntered(MouseEvent e) {
        setText(text,false);
      }
      public void mouseExited(MouseEvent e) {
        setText(text,true);
      }
    });
  }

  @Override
  public void setText(String text){
    setText(text,true);
  }

  public void setText(String text, boolean ul){
    String link = ul ? "<u>"+text+"</u>" : text;
    super.setText("<html><span style=\"color: #000099;\">"+
    link+"</span></html>");
    this.text = text;
  }

  public String getRawText(){
    return text;
  }

  private static void open(URI uri) {
    if (Desktop.isDesktopSupported()) {
      Desktop desktop = Desktop.getDesktop();
      try {
        desktop.browse(uri);
      } catch (IOException e) {
        JOptionPane.showMessageDialog(null,
            "Failed to launch the link, your computer is likely misconfigured.",
            "Cannot Launch Link",JOptionPane.WARNING_MESSAGE);
      }
    } else {
      JOptionPane.showMessageDialog(null,
          "Java is not able to launch links on your computer.",
          "Cannot Launch Link", JOptionPane.WARNING_MESSAGE);
    }
  }
}

You could also, for instance, change the link color to purple after being clicked, if that seemed useful. It's all self contained, you simply call:

SwingLink link = new SwingLink("Java", "http://java.sun.com");
mainPanel.add(link);

If <a href="link"> doesn't work, then:

  1. Create a JLabel and add a MouseListener (decorate the label to look like a hyperlink)
  2. Implement mouseClicked() event
  3. In the implementation of mouseClicked() event, perform your action

Have a look at java.awt.Desktop API for opening a link using the default browser (this API is available only from Java6).

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