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Inheritence of a JButton Java - Overriding Method Issue

I am wanting to set the visibility of a JButton to false in another class. So what I am doing is overriding the boolean function I created in StudentAccount named getWriteBtnVisibility() to change the visibility of the button in the HW class. So basically I want to make the JButton invisible in the StudentAccount. Since I want that button to be visible when a different type of account is logged in.
However, the way I am doing it seems not to be working. I have debugged my code and not understanding why it is not overriding the function. If I can get some guidance, I'd greatly appreciate it.
StudentAccount:
import java.awt.EventQueue;
public class StudentAccount extends AccountTemplate {
/**
* Launch the application.
*/
#Override
public String getHomeworkBtnName() {
return "Submit Assignment";
}
#Override
public boolean getWriteBtnVisibility() {
return false;
}
public static void main(String[] args) {
EventQueue.invokeLater(new Runnable() {
public void run() {
try {
StudentAccount window = new StudentAccount();
window.frmAccountTemplate.setVisible(true);
} catch (Exception e) {
e.printStackTrace();
}
}
});
}
}
AccountTemplate:
import java.awt.EventQueue;
import javax.swing.JFrame;
import javax.swing.JButton;
import java.awt.Font;
import java.awt.event.ActionListener;
import java.awt.event.ActionEvent;
public class AccountTemplate extends HW {
protected JFrame frmAccountTemplate;
/**
* Launch the application.
*/
public String getHomeworkBtnName() {
return "Hw";
}
public static void main(String[] args) {
EventQueue.invokeLater(new Runnable() {
public void run() {
try {
AccountTemplate window = new AccountTemplate();
window.frmAccountTemplate.setVisible(true);
} catch (Exception e) {
e.printStackTrace();
}
}
});
}
/**
* Create the application.
*/
public AccountTemplate() {
initialize();
}
/**
* Initialize the contents of the frame.
*/
protected void initialize() {
frmAccountTemplate = new JFrame();
frmAccountTemplate.setTitle(getFrameTitleName());
frmAccountTemplate.setBounds(100, 100, 450, 300);
frmAccountTemplate.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
frmAccountTemplate.getContentPane().setLayout(null);
JButton btnAssignment = new JButton(getHomeworkBtnName());
btnAssignment.addActionListener(new ActionListener() {
public void actionPerformed(ActionEvent e) {
frmAccountTemplate.dispose();
HW.main(null);
}
});
btnAssignment.setFont(new Font("Tahoma", Font.BOLD, 16));
btnAssignment.setBounds(15, 51, 200, 29);
frmAccountTemplate.getContentPane().add(btnAssignment);
}
}
HW:
import java.awt.EventQueue;
import javax.swing.JFrame;
import javax.swing.JOptionPane;
import javax.swing.JScrollPane;
import javax.swing.JTextArea;
import javax.swing.ScrollPaneConstants;
import javax.swing.filechooser.FileSystemView;
import javax.swing.JButton;
import javax.swing.JFileChooser;
import java.awt.event.ActionListener;
import java.io.BufferedReader;
import java.io.BufferedWriter;
import java.io.File;
import java.io.FileReader;
import java.io.FileWriter;
import java.awt.event.ActionEvent;
public class HW {
public JFrame frmHw;
/**
* Launch the application.
*/
public boolean getWriteBtnVisibility() {
return true;
}
public static void main(String[] args) {
EventQueue.invokeLater(new Runnable() {
public void run() {
try {
HW window = new HW();
window.frmHw.setVisible(true);
} catch (Exception e) {
e.printStackTrace();
}
}
});
}
/**
* Create the application.
*/
public HW() {
initialize();
}
/**
* Initialize the contents of the frame.
*/
protected void initialize() {
frmHw = new JFrame();
frmHw.setTitle("HW");
frmHw.setBounds(100, 100, 450, 300);
frmHw.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
frmHw.getContentPane().setLayout(null);
JTextArea jTextArea1 = new JTextArea();
jTextArea1.setBounds(9, 11, 328, 197);
frmHw.getContentPane().add(jTextArea1);
JScrollPane scrollBar = new JScrollPane(jTextArea1);
scrollBar.setVerticalScrollBarPolicy(ScrollPaneConstants.VERTICAL_SCROLLBAR_ALWAYS);
scrollBar.setHorizontalScrollBarPolicy(ScrollPaneConstants.HORIZONTAL_SCROLLBAR_ALWAYS);
frmHw.getContentPane().add(scrollBar);
scrollBar.setBounds(13, 39, 413, 189);
JButton btnWriteText = new JButton("Write Text");
btnWriteText.setVisible(getWriteBtnVisibility());
btnWriteText.setBounds(154, 11, 115, 24);
frmHw.getContentPane().add(btnWriteText);
}
}

When you made AccountTemplate extend the HW class, every method that was redefined in AccountTemplate overrided the original method from HW. The getWriteBtnVisibility is checked from within the HW's initialize method, but AccountTemplate's initialize method overrides it. Now StudentAccount inherits the overridden method which does not check for the getWriteBtnVisibility boolean and so the visibility is not modified.
If I understand correctly what you're trying to do is to extend the layout using inheritance, however to do that you need to create seperate methods that create and initialize the interface components and call them as required from class. Now you've only created a seperate method for the button name and visibility, but the method that checks for the visibility boolean has been overridden and no longer gets called.
You will have to redesign your architecture so that:
There is only one JFrame field (unless you want multiple interfaces)
There is only one method that creates the JFrame and sets up the title
All generic interface components are created using a seperate (final) method and can be called when required by the class that inherits it
A simple example
class HW {
public JFrame frame;
public String getFrameName() {
return "HW";
}
public boolean getHWBtnVisibility {return true;}
void setupHWComponents() {
JTextField field = new JTextField();
// ...
this.frame.getContentPane().add(field);
JButton button = new JButton("HW");
button.setVisible(getHWBtnVisibility());
// ...
}
void initFrame() {
this.frame = new JFrame(getFrameName());
// ....
}
void initialize() {
initFrame();
setupHWComponents();
}
}
And
class AccountTemplate {
public void setupTemplateComponents() {
JTextField loginField = new JTextField("login");
super.frame.getContentPane().add(loginField);
// ...
}
#Override
public void initialize() {
// Setup Frame and HW components
// If you dont want HW components, replace with initFrame()
super.initialize();
setupTemplateComponents();
}
}
Then the StudentAccount class can likewise choose what components to use and initialize and which ones it doesn't want and then it can add its own components to the frame.

The initialize method that matters, that sets the button's visibility is the one that is called from the HW class, and that method is only called from within AccountTemplate's button's ActionListener here:
public void actionPerformed(ActionEvent e) {
frmAccountTemplate.dispose();
HW.main(null);
}
Notice that it is a call to the HW main method, and so it is a HW instance that is being created when this happens (since that is what HW main creates), not a StudentAccount instance. This is why your inheritance doesn't work -- there is no inheritance happening when the button is created.
Having said that, I have to state that this code is overly complex, much more than it needs to be, and misuses inheritance in a way that only serves to confuse. Don't use inheritance (or absolute positioning and null layouts) since you're just complicating things needlessly. Simply your code and you will thank me.
If this were my project,
I would create distinct JPanels (not JFrames) for each type of GUI
I would use inheritance only for the program's model, the logical non-GUI aspects of the code, and not for the views (the GUI classes), and would use it very cautiously.
I would swap views using a CardLayout and not swap JFrames

Java SwingWorker with JDialog showing JProgressBar during JDBC network operation

I have a frame which has a button, when it is pressed a JDialog with a progress bar is shown and some data is being fetched using jdbc driver (progress bar is being updated). I needed a cancel button, so I spent some time figuring out how to connect everything. It seems to be working, but I sincerely am not sure if this way is any good. If someone has some spare time please check this code and tell me if anything is wrong with it - mainly with the whole SwingWorker and cancellation stuff.
On my pc (linux) the unsuccessful network connection attempt (someNetworkDataFetching method) takes a whole minute to timeout, do I have to worry about the SwingWorkers which are still working (waiting to connect despite being cancelled) when I try to create new ones?
Note: you need mysql jdbc driver library to run this code.
import java.awt.BorderLayout;
import java.awt.event.ActionEvent;
import java.awt.event.ActionListener;
import java.sql.DriverManager;
import java.sql.SQLException;
import java.util.ArrayList;
import java.util.List;
import java.util.concurrent.CancellationException;
import java.util.concurrent.ExecutionException;
import javax.swing.JButton;
import javax.swing.JDialog;
import javax.swing.JFrame;
import javax.swing.JLabel;
import javax.swing.JProgressBar;
import javax.swing.SwingConstants;
import javax.swing.SwingUtilities;
import javax.swing.SwingWorker;
public class Test extends JFrame {
private JProgressBar progressBar = new JProgressBar();
private JLabel label = new JLabel();
private DataFetcherProgress dfp;
/**
* This class holds retrieved data.
*/
class ImportantData {
ArrayList<String> chunks = new ArrayList<>();
void addChunk(String chunk) {
// Add this data
chunks.add(chunk);
}
}
/**
* This is the JDialog which shows data retrieval progress.
*/
class DataFetcherProgress extends JDialog {
JButton cancelButton = new JButton("Cancel");
DataFetcher df;
/**
* Sets up data fetcher dialog.
*/
public DataFetcherProgress(Test owner) {
super(owner, true);
getContentPane().add(progressBar, BorderLayout.CENTER);
// This button cancels the data fetching worker.
cancelButton.addActionListener(new ActionListener() {
#Override
public void actionPerformed(ActionEvent e) {
df.cancel(true);
}
});
getContentPane().add(cancelButton, BorderLayout.EAST);
setLocationRelativeTo(owner);
setSize(200, 50);
df = new DataFetcher(this);
}
/**
* This executes data fetching worker.
*/
public void fetchData() {
df.execute();
}
}
class DataFetcher extends SwingWorker<ImportantData, Integer> {
DataFetcherProgress progressDialog;
public DataFetcher(DataFetcherProgress progressDialog) {
this.progressDialog = progressDialog;
}
/**
* Update the progress bar.
*/
#Override
protected void process(List<Integer> chunks) {
if (chunks.size() > 0) {
int step = chunks.get(chunks.size() - 1);
progressBar.setValue(step);
}
}
/**
* Called when worker finishes (or is cancelled).
*/
#Override
protected void done() {
System.out.println("done()");
ImportantData data = null;
try {
data = get();
} catch (InterruptedException | ExecutionException | CancellationException ex) {
System.err.println("done() exception: " + ex);
}
label.setText(data != null ? "Retrieved data!" : "Did not retrieve data.");
progressDialog.setVisible(false);
}
/**
* This pretends to do some data fetching.
*/
private String someNetworkDataFetching() throws SQLException {
DriverManager.getConnection("jdbc:mysql://1.1.1.1/db", "user", "pass");
// Retrieve data...
return "data chunk";
}
/**
* This tries to create ImportantData object.
*/
#Override
protected ImportantData doInBackground() throws Exception {
// Show the progress bar dialog.
SwingUtilities.invokeLater(new Runnable() {
#Override
public void run() {
dfp.setVisible(true);
}
});
ImportantData data = new ImportantData();
try {
int i = 0;
// There is a network operation here (JDBC data retrieval)
String chunk1 = someNetworkDataFetching();
if (isCancelled()) {
System.out.println("DataFetcher cancelled.");
return null;
}
data.addChunk(chunk1);
publish(++i);
// And another jdbc data operation....
String chunk2 = someNetworkDataFetching();
if (isCancelled()) {
System.out.println("DataFetcher cancelled.");
return null;
}
data.addChunk(chunk2);
publish(++i);
} catch (Exception ex) {
System.err.println("doInBackground() exception: " + ex);
return null;
}
System.out.println("doInBackground() finished");
return data;
}
}
/**
* Set up the main window.
*/
public Test() {
setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
label.setHorizontalAlignment(SwingConstants.CENTER);
getContentPane().add(label, BorderLayout.CENTER);
// Add a button starting data fetch.
JButton retrieveButton = new JButton("Do it!");
retrieveButton.addActionListener(new ActionListener() {
#Override
public void actionPerformed(ActionEvent e) {
fetchData();
}
});
getContentPane().add(retrieveButton, BorderLayout.EAST);
setSize(400, 75);
setLocationRelativeTo(null);
progressBar.setMaximum(2);
}
// Shows new JDialog with a JProgressBar and calls its fetchData()
public void fetchData() {
label.setText("Retrieving data...");
dfp = new DataFetcherProgress(this);
dfp.fetchData();
}
public static void main(String[] args) {
java.awt.EventQueue.invokeLater(new Runnable() {
#Override
public void run() {
try {
// Use jdbc mysql driver
Class.forName("com.mysql.jdbc.Driver");
} catch (ClassNotFoundException ex) {
ex.printStackTrace();
return;
}
// Show the Frame
new Test().setVisible(true);
}
});
}
}

About the only thing I might do different is not use the SwingUtilities.invokeLater in the doInBackground method to show the dialog, but maybe use a PropertyChangeListener to monitor the changes to the state property worker.
I would also use the PropertyChangeListener to monitor the changes to the progress property of the worker. Instead of using publish to indicate the progression changes I would use the setProgress method (and getProgress in the PropertyChangeListener)
For example...java swingworker thread to update main Gui
I might also consider creating the UI on a JPanel and adding it to the JDialog rather then extending directory from JDialog as it would give the oppurtunity to re-use the panel in other ways, should you wish...

Java Swing second window calls event listener twice after being disposed

So I have a swing application where a button opens up a window. It is pretty simple, to open it I use:
private static logPicker logWindow;
static boolean logViewerOpen = false;
if (!logViewerOpen) {
logWindow = new logPicker();
logWindow.frmOpenLog.setVisible(true);
logViewerOpen = true;
}
else {
logWindow.frmOpenLog.requestFocus();
}
I also have a window listener to know when the viewer is closed:
frmOpenLog.addWindowListener(new WindowAdapter() {
#Override
public void windowClosing(WindowEvent arg0) {
indexPage.logViewerOpen = false;
frmOpenLog.dispose();
}
});
I do this because I want to keep track on whether or not the window is already open, because if it is then I have to update information. The window I open has a list of logs that a user can double click on to view the information about that log. The problem right now is, when a user double clicks on the list it gets called however many times I have opened and closed that window. example: I open the log picker window, and then close it. I open it again and double click on the log I want to view, and it will open 2 of those. I have the double click simple do a .doClick() on the Open Log button. The weird thing is, when I use the button to open the log, it does not do this. It will only open the log once. Here is the code for the double click event and the Open Log button.
#Override
public void mouseClicked(MouseEvent arg0) {
if (arg0.getClickCount() == 2) {
btnOpenLog.doClick();
}
}
btnOpenLog.addActionListener(new ActionListener() {
public void actionPerformed(ActionEvent e) {
logViewer window = new logViewer(log.getSelectedValue());
window.frmLogViewer.setVisible(true);
}
});

#LiverpoolFTW: Please provide a SSCCE demonstrating the problem. Absent sufficient code, I speculate you're (re-)adding the MouseListener/MouseAdapter each time your window is opened. The following example works as desired as-is, incrementing the clickCount once per button press or label double-click. But if you uncomment the indicated section, you'll see that the doClick() is executed twice when you double-click the label. If you have, for example, some component to which you're adding a listener each time the window opens, each of those listeners will be executed.
package example.stackoverflow;
import java.awt.event.ActionEvent;
import java.awt.event.ActionListener;
import java.awt.event.MouseAdapter;
import java.awt.event.MouseEvent;
import javax.swing.BoxLayout;
import javax.swing.JButton;
import javax.swing.JFrame;
import javax.swing.JLabel;
import javax.swing.SwingUtilities;
public class ClickCheck extends JFrame
{
private static final long serialVersionUID = -6446528001976145548L;
private static final JButton btnOpenLog = new JButton("Open Log");
public ClickCheck()
{
JLabel label = new JLabel("Double-Click Me");
label.addMouseListener(new MouseAdapter()
{
#Override
public void mouseClicked(MouseEvent arg0) {
if (arg0.getClickCount() == 2) {
btnOpenLog.doClick();
}
}
});
// Uncomment to demonstrate the effect of multiple listeners
// label.addMouseListener(new MouseAdapter()
// {
// #Override
// public void mouseClicked(MouseEvent arg0) {
// if (arg0.getClickCount() == 2) {
// btnOpenLog.doClick();
// }
// }
// });
btnOpenLog.addActionListener(new ActionListener() {
private int clickCount = 0;
public void actionPerformed(ActionEvent e) {
System.out.println(++clickCount + ": Button clicked");
}
});
setSize(200, 200);
setLayout(new BoxLayout(getContentPane(), BoxLayout.Y_AXIS));
add(btnOpenLog);
add(label);
setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
}
public static void main(String[] args)
{
SwingUtilities.invokeLater(new Runnable()
{
public void run()
{
ClickCheck c = new ClickCheck();
c.setVisible(true);
}
});
}
}

How do I create an event handler for a JLabel?

I want to make it so that if I click on the JLabel, the label becomes a new label with another image attached to it.
So far my code looks like:
public class Picture extends JFrame {
private ImageIcon _image1;
private ImageIcon _image2;
private JLabel _mainLabel;
private JLabel _mainLabel2;
public Picture(){
_image1 = new ImageIcon("src/classes/picture1.jpg");
_image2 = new ImageIcon("src/classes/picture2.jpg");
_mainLabel = new JLabel(_image1);
_mainLabel2 = new JLabel(_image2);
add(_mainLabel);
pack();
setVisible(true);
setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
}
}

Add mouseListener to your JLable and in mouseClicked(mouseEvent) method change icon of JLabel.
A sample code may be:
jLabel.addMouseListener(new MouseAdapter() {
#Override
public void mouseClicked(MouseEvent e) {
jLabel.setIcon(newIcon);
}
});

Try using a JToggleButton instead. No need for a MouseListener, and responds to keyboard input.
import javax.swing.*;
import javax.imageio.ImageIO;
import java.net.URL;
import java.awt.Image;
class ToggleImage {
public static void main(String[] args) throws Exception {
URL url1 = new URL("http://pscode.org/media/stromlo1.jpg");
URL url2 = new URL("http://pscode.org/media/stromlo2.jpg");
final Image image1 = ImageIO.read(url1);
final Image image2 = ImageIO.read(url2);
SwingUtilities.invokeLater(new Runnable() {
public void run() {
JToggleButton button = new JToggleButton();
button.setIcon(new ImageIcon(image1));
button.setSelectedIcon(new ImageIcon(image2));
button.setBorderPainted(false);
button.setContentAreaFilled(false);
JOptionPane.showMessageDialog(null, button);
}
});
}
}
Old Code - before I realized this was about images
I want to make it so that if I click on the JLabel
What about for people who are 'mouse challenged? Use a JTextField instead. Tab to any link and hit Enter to activate.
import java.awt.Desktop;
import java.awt.Color;
import java.awt.Cursor;
import java.awt.BorderLayout;
import java.awt.GridLayout;
import java.awt.event.*;
import javax.swing.JTextField;
import javax.swing.JPanel;
import javax.swing.JOptionPane;
import javax.swing.SwingUtilities;
import javax.swing.border.MatteBorder;
import javax.swing.border.Border;
import java.net.URI;
import java.io.File;
/**
A Java 1.6+ LinkLabel that uses the Desktop class for opening
the document of interest.
The Desktop.browse(URI) method can be invoked from applications,
applets and apps. launched using Java Webstart. In the latter
two cases, the usual fall-back methods are used for sandboxed apps
(see the JavaDocs for further details).
While called a 'label', this class actually extends JTextField,
to easily allow the component to become focusable using keyboard
navigation.
To successfully browse to a URI for a local File, the file name
must be constructed using a canonical path.
#author Andrew Thompson
#version 2008/08/23
*/
public class LinkLabel
// we extend a JTextField, to get a focusable component
extends JTextField
implements MouseListener, FocusListener, ActionListener {
/** The target or href of this link. */
private URI target;
public Color standardColor = new Color(0,0,255);
public Color hoverColor = new Color(255,0,0);
public Color activeColor = new Color(128,0,128);
public Color transparent = new Color(0,0,0,0);
public boolean underlineVisible = true;
private Border activeBorder;
private Border hoverBorder;
private Border standardBorder;
/** Construct a LinkLabel that points to the given target.
The URI will be used as the link text.*/
public LinkLabel(URI target) {
this( target, target.toString() );
}
/** Construct a LinkLabel that points to the given target,
and displays the text to the user. */
public LinkLabel(URI target, String text) {
super(text);
this.target = target;
}
/* Set the active color for this link (default is purple). */
public void setActiveColor(Color active) {
activeColor = active;
}
/* Set the hover/focused color for this link (default is red). */
public void setHoverColor(Color hover) {
hoverColor = hover;
}
/* Set the standard (non-focused, non-active) color for this
link (default is blue). */
public void setStandardColor(Color standard) {
standardColor = standard;
}
/** Determines whether the */
public void setUnderlineVisible(boolean underlineVisible) {
this.underlineVisible = underlineVisible;
}
/* Add the listeners, configure the field to look and act
like a link. */
public void init() {
this.addMouseListener(this);
this.addFocusListener(this);
this.addActionListener(this);
setToolTipText(target.toString());
if (underlineVisible) {
activeBorder = new MatteBorder(0,0,1,0,activeColor);
hoverBorder = new MatteBorder(0,0,1,0,hoverColor);
standardBorder = new MatteBorder(0,0,1,0,transparent);
} else {
activeBorder = new MatteBorder(0,0,0,0,activeColor);
hoverBorder = new MatteBorder(0,0,0,0,hoverColor);
standardBorder = new MatteBorder(0,0,0,0,transparent);
}
// make it appear like a label/link
setEditable(false);
setForeground(standardColor);
setBorder(standardBorder);
setCursor( new Cursor(Cursor.HAND_CURSOR) );
}
/** Browse to the target URI using the Desktop.browse(URI)
method. For visual indication, change to the active color
at method start, and return to the standard color once complete.
This is usually so fast that the active color does not appear,
but it will take longer if there is a problem finding/loading
the browser or URI (e.g. for a File). */
public void browse() {
setForeground(activeColor);
setBorder(activeBorder);
try {
Desktop.getDesktop().browse(target);
} catch(Exception e) {
e.printStackTrace();
}
setForeground(standardColor);
setBorder(standardBorder);
}
/** Browse to the target. */
public void actionPerformed(ActionEvent ae) {
browse();
}
/** Browse to the target. */
public void mouseClicked(MouseEvent me) {
browse();
}
/** Set the color to the hover color. */
public void mouseEntered(MouseEvent me) {
setForeground(hoverColor);
setBorder(hoverBorder);
}
/** Set the color to the standard color. */
public void mouseExited(MouseEvent me) {
setForeground(standardColor);
setBorder(standardBorder);
}
public void mouseReleased(MouseEvent me) {}
public void mousePressed(MouseEvent me) {}
/** Set the color to the standard color. */
public void focusLost(FocusEvent fe) {
setForeground(standardColor);
setBorder(standardBorder);
}
/** Set the color to the hover color. */
public void focusGained(FocusEvent fe) {
setForeground(hoverColor);
setBorder(hoverBorder);
}
public static void main(String[] args) {
SwingUtilities.invokeLater(new Runnable() {
public void run() {
try {
File f = new File(".","LinkLabel.java");
/* Filename must be constructed with a canonical path in
order to successfully use Desktop.browse(URI)! */
f = new File(f.getCanonicalPath());
JPanel p = new JPanel(new GridLayout(0,1));
URI uriFile = f.toURI();
LinkLabel linkLabelFile = new LinkLabel(uriFile);
linkLabelFile.init();
p.add(linkLabelFile);
LinkLabel linkLabelWeb = new LinkLabel(
new URI("http://pscode.org/sscce.html"),
"SSCCE");
linkLabelWeb.setStandardColor(new Color(0,128,0));
linkLabelWeb.setHoverColor(new Color(222,128,0));
linkLabelWeb.init();
/* This shows a quirk of the LinkLabel class, the
size of the text field needs to be constrained to
get the underline to appear properly. */
p.add(linkLabelWeb);
LinkLabel linkLabelConstrain = new LinkLabel(
new URI("http://stackoverflow.com/"),
"Stack Overflow");
linkLabelConstrain.init();
/* ..and this shows one way to constrain the size
(appropriate for this layout).
Similar tricks can be used to ensure the underline does
not drop too far *below* the link (think BorderLayout
NORTH/SOUTH).
The same technique can also be nested further to produce
a NORTH+EAST packing (for example). */
JPanel labelConstrain = new JPanel(new BorderLayout());
labelConstrain.add( linkLabelConstrain, BorderLayout.EAST );
p.add(labelConstrain);
LinkLabel linkLabelNoUnderline = new LinkLabel(
new URI("http://java.net/"),
"java.net");
// another way to deal with the underline is to remove it
linkLabelNoUnderline.setUnderlineVisible(false);
// we can use the methods inherited from JTextField
linkLabelNoUnderline.
setHorizontalAlignment(JTextField.CENTER);
linkLabelNoUnderline.init();
p.add(linkLabelNoUnderline);
JOptionPane.showMessageDialog( null, p );
} catch(Exception e) {
e.printStackTrace();
}
}
});
}
}

You cannot simply add an actionListener, you need to implement MouseListener, something like this.

If you are looking for Customized JLable with different font and size and mouse action listeners just go through this.
This is fully tested with following tasks
1.JLabel with Image and Text.
2.Jlabel with Mouse Listners.
3.On hover action with image and text replacement.
public class CustomJLabel extends JLabel implements MouseListener
{
private Color color;
private int width=0;
private int height=0;
private ImageIcon normal_icon;
private ImageIcon hover_icon;
private ImageIcon icon_Label;
JLabel label;
private boolean isMatch;
public CustomJLabel(ImageIcon icon,ImageIcon icon1, String text, int i, int j) {
this.normal_icon=icon;
this.hover_icon=icon1;
this.icon_Label=normal_icon;
setFont(new Font("Tw Cen MT", Font.TYPE1_FONT, 16));
setForeground(Color.WHITE);
setOpaque(false);
setHorizontalAlignment( SwingConstants.CENTER );
setText(text);
addMouseListener(this) ;
}
public CustomJLabel(ImageIcon icon,ImageIcon icon1, int i, int j) {
this.normal_icon=icon;
this.hover_icon=icon1;
this.icon_Label=normal_icon;
setText("");
setVerticalAlignment( SwingConstants.CENTER);
setForeground(Color.WHITE);
setOpaque(false);
addMouseListener(this) ;
}
public CustomJLabel(ImageIcon icon,ImageIcon icon1, String text, int i, int j,Font f) {
this.normal_icon=icon;
this.hover_icon=icon1;
this.icon_Label=normal_icon;
this.width=i;
this.height=j;
setFont(f);
setForeground(Color.WHITE);
setOpaque(false);
setText(text);
setVerticalAlignment( SwingConstants.TOP);
addMouseListener(this) ;
}
public int getIconWidth(){
return width;
}
public int getIconHeight(){
return height;
}
#Override
public void paintComponent(Graphics g) {
if(this.width !=0 && this.height!=0){
super.paintComponent(g);
icon_Label.paintIcon(this, g, this.width, this.height);
}
else{
g.drawImage(icon_Label.getImage(),0,0, null);
super.paintComponent(g);
}
}
#Override
public void mouseClicked(MouseEvent arg0) {
// TODO Auto-generated method stub
}
#Override
public void mouseEntered(MouseEvent me) {
// TODO Auto-generated method stub
if(hover_icon!=null){
this.icon_Label=hover_icon;
this.repaint();
this.revalidate();
}
else{
this.icon_Label=normal_icon;
this.repaint();
this.revalidate();
}
}
#Override
public void mouseExited(MouseEvent arg0) {
// TODO Auto-generated method stub
if(normal_icon!=null){
this.icon_Label=normal_icon;
this.repaint();
this.revalidate();
}
else{
this.icon_Label=hover_icon;
this.repaint();
this.revalidate();
}
}
#Override
public void mousePressed(MouseEvent arg0) {
// TODO Auto-generated method stub
}
#Override
public void mouseReleased(MouseEvent arg0) {
// TODO Auto-generated method stub
}
}
//Here Usage of custom JLabel
JLabel customLabel;
customLabel=new CustomLabel(imageicon1,imageicon2,text,0,0)
//Here
Imageiocn1= Initial icon for JLabel.
Imageicon2= Onhover image for JLabel.
Text = Some String for setting name for JLabel.

Is there an alternative to JPasswordField?

When typing a passphrase like
yeast bulk seize is shows pain
everybody can hear tapping the space bar, so it seems logical to display the spaces in the password field, too. So I'd like something capable of showing
***** **** ***** ** ***** ****
instead of
******************************
This would make typing easier while hardly decreasing the security.
UPDATE
Think twice before you update Riduidel's comment. When Bruce Schneier writes "It's time to show most passwords in clear text", then showing a small part of it must be correct, too. Especially showing a part which may get captured simply by listening.

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);
}
}

Was thinking JPasswordField was simply a JTextField simply overriding the renderer component, but it seems not to be the case.
So, instead of changing the renderer (like it would be the case if JTextField had such a component), you'll have to use a JTextField with a custom Document holding two strings :
Password text as written by user
Displayed password
You'll have to make sure all Document modifying methods change the password text, while all rendering methods use the displayed one.