Here’s a variation that uses setEchoChar()
to make the password visible for a predefined time: three seconds for example.
import java.awt.event.ActionEvent;
import java.awt.event.ActionListener;
import javax.swing.JFrame;
import javax.swing.JPasswordField;
import javax.swing.Timer;
import javax.swing.event.DocumentEvent;
import javax.swing.event.DocumentListener;
/** @see http://stackoverflow.com/questions/5339702 */
public class PasswordTest {
public static void main(String[] args) {
javax.swing.SwingUtilities.invokeLater(new Runnable() {
public void run() {
createAndShowGui();
}
});
}
private static void createAndShowGui() {
JFrame jf = new JFrame("Test Password");
JPasswordField jpwd = new JPasswordField();
TimedPasswordListener tpl = new TimedPasswordListener(jpwd);
jpwd.getDocument().addDocumentListener(tpl);
jf.add(jpwd);
jf.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
jf.setLocationRelativeTo(null);
jf.pack();
jf.setVisible(true);
}
}
class TimedPasswordListener implements DocumentListener, ActionListener {
private Timer timer = new Timer(3000, this);
private char echoChar;
private JPasswordField pwf;
public TimedPasswordListener(JPasswordField jp) {
pwf = jp;
timer.setRepeats(false);
}
public void insertUpdate(DocumentEvent e) {
showText(e);
}
public void removeUpdate(DocumentEvent e) {
showText(e);
}
public void changedUpdate(DocumentEvent e) {}
public void showText(DocumentEvent e) {
if (0 != pwf.getEchoChar()) {
echoChar = pwf.getEchoChar();
}
pwf.setEchoChar((char) 0);
timer.restart();
}
public void actionPerformed(ActionEvent e) {
pwf.setEchoChar(echoChar);
}
}