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Why doesn't the value passed to a method of a different class reflect in Java (using NetBeans 7.01)?

Before I start, Hi. This is is my first question here. I am not good with Java so have been trying and improve that and here it goes.
I am trying to create an email client and server application using sockets in Java. However I have been running into a problem. I have created a jFrame which is basically the Welcome window. The code is too huge to post so I'll post the relevant portions. There is a preferences jDialog. When the OK button on the dialog, an action handler comes in to play. The code:
private void okActionPerformed(java.awt.event.ActionEvent evt) {
Welcome wel = new Welcome();
wel.setStatusBar("Pressed OK");
dispose();
}
Obviously, the setStatusBar() sets the text of the statusLabel. The code for setStatusBar():
public void setStatusBar(String s)
{
statusLabel.setText(s);
}
Also, the preferences dialog is opened through menu item with this code:
private void jMenuItem2ActionPerformed(java.awt.event.ActionEvent evt) {
settings pref=new settings(null,true);
pref.show();
}
The problem is if I set the status label from any other class, for instance settings class, it does not reflect but if I do so from the Welcome class ( the class where the statusLabel is present), it works fine. This problem is not only limited to this setStatus() but virtually pops up whenever I try to use a method of a different class.
If you guys need more of the code, I could post it. I would be grateful if could help a Java beginner out.
Thanks.

private void okActionPerformed(java.awt.event.ActionEvent evt) {
Welcome wel = new Welcome();
wel.setStatusBar("Pressed OK");
dispose();
}
You're creating a new (hence the keyword new) object of type Welcome. This new object is different from the already existing object of type Welcome, that you have created earlier. It thus has its own label, and you're setting the text of this different label, which is not displayed anywhere in the screen.
Java objects work like regular object. Let's say you would like a cool logo on one of your blue t-shirts. You go to a T-shirt vendor and ask him to print a cool logo. The vendor doesn't have your blue t-shirt. If the vendor gets another red t-shirt from his shop and prints the logo on this red t-shirt, your blue t-shirt will still have no logo at all.
For the vendor to be able to print a logo on your blue t-shirt, you need to give him this blue t-shirt. Same in Java: you need to pass the existing Welcome object to the preferences dialog, and the actionPerformed method must set the label on this Welcome object. Not on a new Welcome object.

How to name application and give it an icon?

I'm working in eclipse and I have made an application without name and icon. When i start the application it's a really creepy name displaying in the upper left corner (Mac). It's some thing like. I wonder how I can change this to my own name. Second question is how i can change the icon. Can I do that in eclipse?

If you're using JFrames, you can try setting the icon image as follows.
frame.setIconImage(img);
Also, by name it sounds a bit like you mean the frame's title. When you create the a frame, you can set the title as follows:
Frame frame = new JFrame("Title goes here");

To change name: How to change an Android app's name?
To change icon: How to change the icon of an Android app in Eclipse?
It's already here at stackoverflow, please check if your answers are here before posting.

The prefered method would be to create a Mac OS application bundle (and the bundler), but if this seems like to much work, you can supply custom properties to, for example, you could supply the Xdock:name property when running the application, for example...
-DXdock:name="Application Name"
If you can't do that, you can set it when your application runs, for example...
public static void main(String[] args) {
try {
// Sets the application name on the menu bar
System.setProperty("Xdock:name", "Application Name");
// Set the applications dock icon...
Application application = Application.getApplication();
application.setDockIconImage(ImageIO.read(TestDockIcon.class.getResource("/Icon.png")));
// Start the application...
new TestDockIcon();
} catch (IOException exp) {
exp.printStackTrace();
}
}

Malformed Farsi characters on AWT

When I started programming with the JDK6, I had no problem with text components, neither in AWT nor in Swing.
But for labels or titles of AWT components I do have a problem. I can't display Farsi characters on AWTs components (in Swing I type them into the source code).
Here's my sample code:
import javax.swing.*;
import java.awt.*;
import java.io.*;
import java.util.Properties;
public class EmptyFarsiCharsOnAWT extends JFrame{
public EmptyFarsiCharsOnAWT() {
super("مثال");
setDefaultCloseOperation(3);
setVisible(rootPaneCheckingEnabled);
}
public static void main(String[] args) throws AWTException, IOException {
JFrame jFrame = new EmptyFarsiCharsOnAWT();
MenuItem show ;
// approach 1 = HardCoding :
/*
show = new MenuItem("\u0646\u0645\u0627\u06cc\u0634");
*
*/
// approach 2 = using simple utf-8 saved text file :
/*
BufferedReader in = new BufferedReader(new FileReader("farsiLabels.txt"));
String showLabel = in.readLine();
in.close();
show = new MenuItem(showLabel);
*
*/
// approach 3 = using properties file :
FileReader in = new FileReader("farsiLabels.properties");
Properties farsiLabels = new Properties();
farsiLabels.load(in);
show = new MenuItem(farsiLabels.getProperty("tray.show"));
PopupMenu popUp = new PopupMenu();
popUp.add(show);
// creating Tray object
Image iconIamge = Toolkit.getDefaultToolkit().getImage("greenIcon.png");
TrayIcon trayIcon = new TrayIcon(iconIamge, null, popUp);
SystemTray tray = SystemTray.getSystemTray();
tray.add(trayIcon);
jFrame.setIconImage(iconIamge);
}
}
These three approaches all work when run with an IDE, but when I make a JAR containing this class (by means of NetBeans > project > clean & build), I don't see the expected characters (it shows EMPTY/BLANK SQUARES)!
Note:
It seems I can not attach anything, so the contents of the text file would be this: نمایش and the contents of properties file:
#Sun May 02 09:45:10 IRDT 2010
tray.show=نمایش
And I think I have to let you know that I posted this question a while ago on SDN and "the Java Ranch" forums and other native forums and still I'm waiting...
By the way I am using latest version of Netbeans IDE...
I will be grateful if anybody has a solution to these damn AWT components never rendering any Farsi character for me...

I suspect that this is platform related. Your example appears to work on my platform using approach 1 in either Netbeans or the command line; I didn't try the other approaches.
There might be a disparity between the IDE and the command line with regard to the default character encoding. I've noticed that NetBeans, Eclipse and many consoles can be set to something other than the platform default. Here's code to check:
System.out.println(System.getProperty("file.encoding"));
System.out.println(Charset.defaultCharset().name());
You might look at this related question, too.
Addendum: Note show string changed to match the JFrame title for comparison. The title and menu look the same from NetBeans' Run > Run Project as well as via these command lines:
$ java -cp build/classes EmptyFarsiCharsOnAWT
$ java -jar dist/test6.jar
import javax.swing.*;
import java.awt.*;
import java.io.*;
public class EmptyFarsiCharsOnAWT extends JFrame{
public EmptyFarsiCharsOnAWT() {
super("مثال");
setDefaultCloseOperation(3);
setVisible(rootPaneCheckingEnabled);
}
public static void main(String[] args) throws AWTException, IOException {
JFrame jFrame = new EmptyFarsiCharsOnAWT();
MenuItem show ;
// approach 1 = HardCoding :
show = new MenuItem("\u0645\u062b\u0627\u0644");
PopupMenu popUp = new PopupMenu();
popUp.add(show);
// creating Tray object
Image iconIamge = Toolkit.getDefaultToolkit().getImage("image.jpg");
TrayIcon trayIcon = new TrayIcon(iconIamge, null, popUp);
SystemTray tray = SystemTray.getSystemTray();
tray.add(trayIcon);
jFrame.setIconImage(iconIamge);
}
}

The most exciting part of your reply was:
"$ java -jar dist/test6.jar" !
Does it really shows the real characters (just like the frame title)?!
and not boxes or garbage ?
I'm sorry if I believe it hard, because the only problem in my developing work with Java took such long without any answer nor from searching, nor asking in forums is this!
So, what can I do? what font should I use? Unfortunately I'm not so familiar with fonts, until now I've just used global fonts in Java (Serif,SansSerif,etc.) and only modified their size or style, but after you suggest I examined several Persian ttf fonts through these codes:
File fontFile = new File("F_JADID.TTF");
Font font = Font.createFont(Font.TRUETYPE_FONT, fontFile);
show.setFont(font.deriveFont(15f));
but just boxes was the result! (just using HardCoding)
I think i should mention that my envirounment is win xp and i have this problem not only in my machine, but another running xp os too. And I'm using jdk6u17.
I can be agree with you in suspecting the fonts, because encoding problem (in my experience) appears with question mark, but garbage or empty boxes related to rendering characters.
But still i have the problem, just like the first day :(
What font you use and another question i encountered is:
Why swing doesn't have any problem without specifying the font, but AWT.
Addendum: Thanks to Oscar Reyes in this page for giving this link and thanks to StackOverflow :)
They saved me! from this section i should quote:
An application using peered AWT components can only use logical font names.
and from this section should quote:
For applications using AWT peered components, Sun's JREs select fonts for Chinese, Japanese, or Korean only when running on host operating systems localized for these specific languages
Yes, you guess right! by setting the OS locale to Farsi, i got the right result.
but i still should research and see how is it possible to have the right result by not setting the right locale, from that article.
I will explain how, when i got the result, but still will listen to here. wish me luck.

Why my Swing based GUI application is not responding?

I am trying to create my first GUI application using (Java + Eclipse + Swing). This is my code:
import java.awt.*;
import javax.swing.*;
public class HelloWorldSwing extends JFrame {
JTextArea m_resultArea = new JTextArea(6, 30);
//====================================================== constructor
public HelloWorldSwing() {
//... Set initial text, scrolling, and border.
m_resultArea.setText("Enter more text to see scrollbars");
JScrollPane scrollingArea = new JScrollPane(m_resultArea);
scrollingArea.setBorder(BorderFactory.createEmptyBorder(10,5,10,5));
// Get the content pane, set layout, add to center
Container content = this.getContentPane();
content.setLayout(new BorderLayout());
content.add(scrollingArea, BorderLayout.CENTER);
this.pack();
}
//============================================================= main
public static void main(String[] args) {
JFrame win = new HelloWorldSwing();
win.setTitle("TextAreaDemo");
win.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
win.setVisible(true);
}
}
The code was taken from here.
When I run the application from Eclipse the expected window appears (So, it's good. I see what I want to see). However, when I try to close the window or try to write something in the text area the program freezes. The OS writes me that program is not responding (I try it on Ubuntu).
Can anybody help me to find the reason of the problem?
Thank you in advance for any help.

I'm sure this doesn't have to do with the code, as others have found the code runs just fine on their machines - which points to a machine specific issue. From within Eclipse, make sure it is setup to use the expected JDK/JRE. However, before worrying about how Eclipse is handling your situation, I'd run things by hand first - especially since you've got a very simple class.
I would check to ensure that you're using the expected compiler and runtime. On Linux:
which javac
which java
If they're both what you expect, do the following:
javac HelloWorldSwing.java
java HelloWorldSwing
If you get a similar problem, then you know it's not the Eclipse configuration and it's something else. If you're not using the latest JDK, upgrade to the latest. If you're already at the latest, it could be a display driver. Do other JAVA swing programs work on this computer? I'm sure you could find some on the net, download an app already packaged as a jar and try running it.

did you try using the eventdispatcherthread to view the JFrame?
something like:
public static void main(String[] args){
SwingUtilities.invokeLater(new Runnable(){
public void run(){
createAndViewJFrame();
}
});
}
public void createAndViewJFrame(){
JFrame win = new HelloWorldSwing();
win.setTitle("TextAreaDemo");
win.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
win.setVisible(true);
}
then your frame would be shown by the swing dispatcher thread.
hope it helped, although im just guessing...
Update: as commenters pointed you i f**ed up the invokeLater() call. I just edited this post to correct that. Thanx go to yishai & willcodejavaforfood for pointing it out!
frank

You need to catch the exit event and
respond with a System.exit( 0 );
You should be able to find that in
most swing examples online.
wrong stuff... sorry... coffee... argh....

Creating an offscreen frame in Java (or: how to avoid a blank menu on a Mac, when all application windows are closed)?

I am making a Mac application, and I want my menu bar to look right.
Any Mac user knows the menu bar should be in the top screen menu. Setting apple.laf.useScreenMenuBar to true in the property list file gets rid of the in-frame menu bars and moves the menu bar of the current focused window to the screen menu.
However, when all windows are hidden or when there are no windows, there are no menu bars to move to the top, and you just get a blank menu. I heard a solution to this was to create an offscreen window that is focused when no others are. The only purpose of it would be its menu, so that it could fill in when the others are gone.
However, I've been getting loads of problems. I can't seem to move the window off the screen because Macs won't let you set the coordinates to something past the size of the screen; it just cuts it off and positions it at the edge instead. Is there something else I have to do to make an offscreen window?

You should definitely consider WizardOfOdds' very helpful answer. Using "The Application Menu" correctly will help, and it's easy to set up a minimal Info.plist to get started. A persistent File menu will allow your application to open a new window when others are closed. This answer links to a simple example.
Although Apple's Human Interface Guidelines are an excellent guide to what your users will expect, you can certainly experiment with the approach you suggested in your question. In particular, you might try setLocation(Short.MIN_VALUE, Short.MIN_VALUE) on the invisible window. In addition, you might want to respond to a WindowEvent in some special way if it signals the close of the last visible window.
Addendum: When your listener sees the last visible window close, create a new, empty application window. Alternatively, move the invisible window onscreen and make it visible until the user decides how to proceed.
Addendum: Mac OS X helpfully prevents a visible window form being moved offscreen, but it's easy to put an invisible window in limbo, as shown below.
import java.awt.BorderLayout;
import java.awt.EventQueue;
import java.awt.event.ItemEvent;
import java.awt.event.ItemListener;
import javax.swing.JFrame;
import javax.swing.JPanel;
import javax.swing.JToggleButton;
public class FrameTest extends JFrame {
private static FrameTest marco;
private static FrameTest polo;
private static class MyPanel extends JPanel {
public MyPanel() {
super(true);
final JToggleButton b = new JToggleButton("Test");
b.addItemListener(new ItemListener() {
#Override
public void itemStateChanged(ItemEvent e) {
if (b.isSelected()) {
polo.setLocation(100, 100);
polo.setVisible(true);
}
else {
polo.setVisible(false);
polo.setLocation(Short.MIN_VALUE, Short.MIN_VALUE);
}
}
});
this.add(b);
}
}
public FrameTest(String title) {
super(title);
this.setLayout(new BorderLayout());
this.add(new MyPanel());
this.pack();
this.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
}
public static void main(final String[] args) {
EventQueue.invokeLater(new Runnable() {
#Override
public void run() {
marco = new FrameTest("Marco");
marco.setLocationRelativeTo(null);
marco.setVisible(true);
polo = new FrameTest("Polo");
polo.setLocation(Short.MIN_VALUE, Short.MIN_VALUE);
}
});
}
}

I know that this post is quite old, anyway, I had the same problem and found the solution. Actually it's quite simple. Just don't add the JMenuBar to your main frame when running on mac os x, but to your application using
com.apple.eawt.Application.getApplication().setDefaultMenuBar(menuBar);
Now the MenuBar is still displayed even if you set all frame's visibility to false.

Not a direct solution, but I think some create a 1-pixel window instead. That yields complaints though, like one described at Super User: Chaotic behavior of a dead pixel on my iMac 24"...

First a note: your question seems really to be "How to have a Window menu following the Apple Human Interface Guidelines" and not "creating an offscreen frame in Java", which seems like a monstrous hack.
I suggest checking Apple's "Mac OS X Integration for Java", which, under "Window menu", shows apparently exactly what you're trying to achieve:
Apple Human Interface Guidelines suggests that all Mac OS X applications should provide a Window menu to keep track of all currently open windows. A Window menu should contain a list of windows, with a checkmark next to the active window.

This is a comment to trashgod's answer. It's too big so I have to move it here >.<
More problems!
I'm getting 2 errors:
line 23: The method itemStateChanged(ItemEvent) of type new ItemListener(){} must override a superclass method
line 50:The method run() of type new Runnable(){} must override a superclass method
Any help? I've never encountered this before. I don't know what it means.
EDIT: I have more problems! I need the offscreen window to be visible while it is offscreen for it to produce a menu to move to the screen menu bar. When I use the code
offScreen = new JFrame("WTF?! You can see me?");
offScreen.setSize(400,300);
offScreen.setLocation(0, java.awt.Toolkit.getDefaultToolkit().getScreenSize().height+50);
System.out.println(offScreen.getLocation());
offScreen.setVisible(true);
System.out.println(offScreen.getLocation());
I get the output:
java.awt.Point[x=0,y=1100]
java.awt.Point[x=0,y=961]
It moves it back once it's made visible again!
I've searched for ages and I can't find anything.

This code works in Java 7:
if( isMac ) {
//This creates an invisible frame so that we always have a menu bar visible
JFrame menuFrame = new JFrame();
menuFrame.setUndecorated( true );
menuFrame.setJMenuBar( defaultMenuBar );
AWTUtilities.setWindowOpaque( menuFrame, false );
menuFrame.setBounds( 0,0,1,1 );
menuFrame.setVisible( true );
}
Just call this before you open any other windows, and it will stay in the background and automatically become the focused window when others are closed. You can still use the com.apple.eawt.Application.getApplication().setDefaultMenuBar(menuBar) method in your application so that you don't need to call setJMenuBar() on each JFrame.