How to add hyperlink in JLabel?

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?


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 */ }
  }

I'd like to offer yet another solution. It's similar to the already proposed ones as it uses HTML-code in a JLabel, and registers a MouseListener on it, but it also displays a HandCursor when you move the mouse over the link, so the look&feel is just like what most users would expect. If browsing is not supported by the platform, no blue, underlined HTML-link is created that could mislead the user. Instead, the link is just presented as plain text. This could be combined with the SwingLink class proposed by @dimo414.

public class JLabelLink extends JFrame {

private static final String LABEL_TEXT = "For further information visit:";
private static final String A_VALID_LINK = "http://stackoverflow.com";
private static final String A_HREF = "<a href=\"";
private static final String HREF_CLOSED = "\">";
private static final String HREF_END = "</a>";
private static final String HTML = "<html>";
private static final String HTML_END = "</html>";

public JLabelLink() {
    setTitle("HTML link via a JLabel");
    setDefaultCloseOperation(JFrame.DISPOSE_ON_CLOSE);

    Container contentPane = getContentPane();
    contentPane.setLayout(new FlowLayout(FlowLayout.LEFT));

    JLabel label = new JLabel(LABEL_TEXT);
    contentPane.add(label);

    label = new JLabel(A_VALID_LINK);
    contentPane.add(label);
    if (isBrowsingSupported()) {
        makeLinkable(label, new LinkMouseListener());
    }

    pack();
}

private static void makeLinkable(JLabel c, MouseListener ml) {
    assert ml != null;
    c.setText(htmlIfy(linkIfy(c.getText())));
    c.setCursor(new java.awt.Cursor(java.awt.Cursor.HAND_CURSOR));
    c.addMouseListener(ml);
}

private static boolean isBrowsingSupported() {
    if (!Desktop.isDesktopSupported()) {
        return false;
    }
    boolean result = false;
    Desktop desktop = java.awt.Desktop.getDesktop();
    if (desktop.isSupported(Desktop.Action.BROWSE)) {
        result = true;
    }
    return result;

}

private static class LinkMouseListener extends MouseAdapter {

    @Override
    public void mouseClicked(java.awt.event.MouseEvent evt) {
        JLabel l = (JLabel) evt.getSource();
        try {
            URI uri = new java.net.URI(JLabelLink.getPlainLink(l.getText()));
            (new LinkRunner(uri)).execute();
        } catch (URISyntaxException use) {
            throw new AssertionError(use + ": " + l.getText()); //NOI18N
        }
    }
}

private static class LinkRunner extends SwingWorker<Void, Void> {

    private final URI uri;

    private LinkRunner(URI u) {
        if (u == null) {
            throw new NullPointerException();
        }
        uri = u;
    }

    @Override
    protected Void doInBackground() throws Exception {
        Desktop desktop = java.awt.Desktop.getDesktop();
        desktop.browse(uri);
        return null;
    }

    @Override
    protected void done() {
        try {
            get();
        } catch (ExecutionException ee) {
            handleException(uri, ee);
        } catch (InterruptedException ie) {
            handleException(uri, ie);
        }
    }

    private static void handleException(URI u, Exception e) {
        JOptionPane.showMessageDialog(null, "Sorry, a problem occurred while trying to open this link in your system's standard browser.", "A problem occured", JOptionPane.ERROR_MESSAGE);
    }
}

private static String getPlainLink(String s) {
    return s.substring(s.indexOf(A_HREF) + A_HREF.length(), s.indexOf(HREF_CLOSED));
}

//WARNING
//This method requires that s is a plain string that requires
//no further escaping
private static String linkIfy(String s) {
    return A_HREF.concat(s).concat(HREF_CLOSED).concat(s).concat(HREF_END);
}

//WARNING
//This method requires that s is a plain string that requires
//no further escaping
private static String htmlIfy(String s) {
    return HTML.concat(s).concat(HTML_END);
}

/**
 * @param args the command line arguments
 */
public static void main(String[] args) {
    SwingUtilities.invokeLater(new Runnable() {

        @Override
        public void run() {
            new JLabelLink().setVisible(true);
        }
    });
}
}

I wrote an article on how to set a hyperlink or a mailto on a jLabel.

So just try it :

I think that's exactly what you're searching for.

Here's the complete code example :

/**
 * Example of a jLabel Hyperlink and a jLabel Mailto
 */

import java.awt.Cursor;
import java.awt.Desktop;
import java.awt.EventQueue;
import java.awt.event.MouseAdapter;
import java.awt.event.MouseEvent;
import java.io.IOException;
import java.net.URI;
import java.net.URISyntaxException;
import javax.swing.JFrame;
import javax.swing.JLabel;
import javax.swing.JPanel;

/**
 *
 * @author ibrabelware
 */
public class JLabelLink extends JFrame {
    private JPanel pan;
    private JLabel contact;
        private JLabel website;
    /**
     * Creates new form JLabelLink
     */
    public JLabelLink() {
        this.setTitle("jLabelLinkExample");
        this.setSize(300, 100);
        this.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
        this.setLocationRelativeTo(null);

        pan = new JPanel();
        contact = new JLabel();
        website = new JLabel();

        contact.setText("<html> contact : <a href=\"\">[email protected]</a></html>");
        contact.setCursor(new Cursor(Cursor.HAND_CURSOR));

        website.setText("<html> Website : <a href=\"\">http://www.google.com/</a></html>");
        website.setCursor(new Cursor(Cursor.HAND_CURSOR));

    pan.add(contact);
    pan.add(website);
        this.setContentPane(pan);
        this.setVisible(true);
        sendMail(contact);
        goWebsite(website);
    }

    /**
     * @param args the command line arguments
     */
    public static void main(String args[]) {
        /*
         * Create and display the form
         */
        EventQueue.invokeLater(new Runnable() {

            @Override
            public void run() {
                new JLabelLink().setVisible(true);
            }
        });
    }

    private void goWebsite(JLabel website) {
        website.addMouseListener(new MouseAdapter() {
            @Override
            public void mouseClicked(MouseEvent e) {
                try {
                    Desktop.getDesktop().browse(new URI("http://www.google.com/webhp?nomo=1&hl=fr"));
                } catch (URISyntaxException | IOException ex) {
                    //It looks like there's a problem
                }
            }
        });
    }

    private void sendMail(JLabel contact) {
        contact.addMouseListener(new MouseAdapter() {
            @Override
            public void mouseClicked(MouseEvent e) {
                try {
                    Desktop.getDesktop().mail(new URI("mailto:[email protected]?subject=TEST"));
                } catch (URISyntaxException | IOException ex) {
                    //It looks like there's a problem
                }
            }
        });
    }
}

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);