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Wizard API updated!
Tim Boudreau has released a new version of the Swing Wizard library (version 0.997) that fixes the WizardException bug reported in JavaWorld's recent Open Source Java Project profile. The article's examples have been reworked to test out the new, improved WizardException. Thanks, Tim, for this helpful fix!
Open Source Java Projects: The Wizard API

Authenticator.setDefault (new MyAuthenticator ());

class MyAuthenticator extends Authenticator {  protected PasswordAuthentication getPasswordAuthentication() {
    return new PasswordAuthentication ("username", "password");
  }
}

import java.io.*;
import java.net.*;
import java.awt.*;
import java.awt.event.*;
public class URLPassword extends Frame {
  private TextField tf = new TextField();
  private TextArea  ta = new TextArea();
  public URLPassword() {
    super ("URL Password");
    // Install Authenticator
    Authenticator.setDefault (new MyAuthenticator ());
    // Setup screen
    add (tf, BorderLayout.NORTH);
    ta.setEditable(false);
    add (ta, BorderLayout.CENTER);
    tf.addActionListener (new ActionListener() {
      public void actionPerformed (ActionEvent e) {
        String s = tf.getText();
        if (s.length() != 0)
          ta.setText (fetchURL (s));
      }
    });
    addWindowListener (new WindowAdapter() {
      public void windowClosing (WindowEvent e) {
        dispose();
        System.exit(0);
      }
    });
  }
  private String fetchURL (String urlString) {
    StringWriter sw = new StringWriter();
    PrintWriter  pw = new PrintWriter(sw);
    try {
      URL url = new URL (urlString);
      InputStream content = (InputStream)url.getContent();
      BufferedReader in   = 
        new BufferedReader (new InputStreamReader (content));
      String line;
      while ((line = in.readLine()) != null) {
        pw.println (line);
      }
    } catch (MalformedURLException e) {
      pw.println ("Invalid URL");
    } catch (IOException e) {
      pw.println ("Error reading URL");
    }
    return sw.toString();
  }
  public static void main (String args[]) {
    Frame f = new URLPassword();
    f.setSize(300, 300);
    f.setVisible (true);
  }
  class MyAuthenticator extends Authenticator {
    protected PasswordAuthentication getPasswordAuthentication() {
      final Dialog jd = new Dialog (URLPassword.this, "Enter password", true);
      jd.setLayout (new GridLayout (0, 1));
      Label jl = new Label (getRequestingPrompt());
      jd.add (jl);
      TextField username = new TextField();
      username.setBackground (Color.lightGray);
      jd.add (username);
      TextField password = new TextField();
      password.setEchoChar ('*');
      password.setBackground (Color.lightGray);
      jd.add (password);
      Button jb = new Button ("OK");
      jd.add (jb);
      jb.addActionListener (new ActionListener() {
        public void actionPerformed (ActionEvent e) {
          jd.dispose();
        }
      });
      jd.pack();
      jd.setVisible(true);
      return new PasswordAuthentication (username.getText(), password.getText());
    }
  }
}

return new PasswordAuthentication (username.getText(), password.getText());

URLPass.java:88: Incompatible type for constructor. Can't convert
java.lang.String to char[].
    return new PasswordAuthentication ( username.getText(), password.getText());

return new PasswordAuthentication ( username.getText(), pass.toCharArray());