Out of memory in java swing application

Hi,
I am continously getting out of memory in my java application. I collected the java heap dump and found major memory chunk ( >90%) of total java heap is taken by some "class [I", which is array of 'Inetger' objects and sometimes by "class [S", which is array of 'Short' objects.
Elements of these arrays are referred by:
java.awt.image.DataBufferUShort and
sun.awt.image.ShortInterleavedRaster
and these are consuming major memory chunks.
Has anyone observed this kind of problem?
I am not able to proceed in my analysis and kind of struck at these Integer and Short arrays. Please help.
Thanks
Charanjeet

Sounds like you're retaining a lot of image resources - make sure you're doing the following:
1. flush()ing images once you've used them
2. not retaining references you no longer need
3. not creating duplicate Image objects where not required
4. not creating Image objects which are never needed, or creating a huge pile of images at once when they are not all required at the same time

Similar Messages

Certificate support in Java Swing application

Hi There,
I am new to this Certificate thing and running into issues! Would appreciate for all the help and please ignore for any stupid questions.
Here is my scenario.
1. I do have a client server application and client is a java swing application which connects to a Server application (Using Jetty 4.2.22 as embedded server)
2. Initially, it had a self signed certificate but goal is to support third party certificate (i.e import in the server and then show warning to the client during login)
If somebody has already done this or point me to some example (using Jetty APIs) that would be great help. If not, here is what I am trying to do and some questions.
1. I tried to get some free SSL certificate from the web and imported into the server's KeyStore.
If I do a list from the server using Keystore, this is what it looks like
keytool -list -keystore /tmp/keystore -storepass genview
Keystore type: JKS
Keystore provider: SUN
Your keystore contains 2 entries
self, Dec 3, 2008, PrivateKeyEntry,
Certificate fingerprint (MD5): 0D:58:E8:77:89:09:F8:2B:37:64:37:D5:03:AD:C9:0B
rapid, Jan 6, 2009, trustedCertEntry,
Certificate fingerprint (MD5): 64:9C:EF:2E:44:FC:C6:8F:52:07:D0:51:73:8F:CB:3
QUESTION 1 : why the third party certificate's entry as "trustedCertEntry"? Is it always like this? Do I need to have only one certificate at a time? (If so, just remove the self signed and have 3rd party one)
My Jetty server comes up but when I connect from Client Swing App, the "getServerCertificates()" method only returns one entry i.e self signed one but not the third party one.
I am using like this
URL url = new URL("https://127.0.0.1:port");
HttpsURLConnection conn = (HttpsURLConnection) url.openConnection();
conn.connect();
Certificate[] certs = conn.getServerCertificates();
Is not this API supposed to return all the server's certificate?
Please guide me or instruct me what to do.
Thanks,
CRB

Crossposted and answered.

How to create the digital clock in java swing application ?

I want to create the running digital clock in my java swing application. Can someone throw some light on this how to do this ? Or If someone has done it then can someone pl. paste the code ?
Thanks.

hi prah_Rich,
I have created a digital clock you can use. You will most likely have to change some things to use it in another app although that shouldn't be too hard. A least it can give you some ideas on how to create one of your own. There are three classes.One that creates the numbers. a gui class and frame class.
cheers:)
Hex45
import java.awt.*;
import java.util.*;
import javax.swing.*;
import java.awt.geom.*;
public class DigitalClock extends Panel{
          BasicStroke stroke = new BasicStroke(4,BasicStroke.CAP_ROUND,
                                           BasicStroke.JOIN_BEVEL);
          String hour1, hour2;
          String minute1, minute2;
          String second1, second2;
          String mill1, mill2, mill3;
          int hr1, hr2;
          int min1, min2;
          int sec1, sec2;
          int mll1, mll2,mll3;
    public void update(Graphics g){
         paint(g);
     public void paint(Graphics g){
          Graphics2D g2D = (Graphics2D)g;
          DigitalNumber num = new DigitalNumber(10,10,20,Color.cyan,Color.black);
          GregorianCalendar c = new GregorianCalendar();
          String hour = String.valueOf(c.get(Calendar.HOUR));
          String minute = String.valueOf(c.get(Calendar.MINUTE));
          String second = String.valueOf(c.get(Calendar.SECOND));
          String milliSecond = String.valueOf(c.get(Calendar.MILLISECOND));
          if(hour.length()==2){
               hour1 = hour.substring(0,1);
               hour2 = hour.substring(1,2);
          }else{
               hour1 = "0";
               hour2 = hour.substring(0,1);
          if(minute.length()==2){
               minute1 = minute.substring(0,1);
               minute2 = minute.substring(1,2);
          }else{
               minute1 = "0";
               minute2 = minute.substring(0,1);
          if(second.length()==2){
               second1 = second.substring(0,1);
               second2 = second.substring(1,2);
          }else{
               second1 = "0";
               second2 = second.substring(0,1);
          if(milliSecond.length()==3){
               mill1 = milliSecond.substring(0,1);
               mill2 = milliSecond.substring(1,2);
               mill3 = milliSecond.substring(2,3);
          }else if(milliSecond.length()==2){
               mill1 = "0";
               mill2 = milliSecond.substring(0,1);
               mill3 = milliSecond.substring(1,2);
          }else{
               mill1 = "0";
               mill2 = "0";
               mill3 = milliSecond.substring(0,1);
          hr1 = Integer.parseInt(hour1);
          hr2 = Integer.parseInt(hour2);
          min1 = Integer.parseInt(minute1);
          min2 = Integer.parseInt(minute2);
          sec1 = Integer.parseInt(second1);
          sec2 = Integer.parseInt(second2);
          mll1 = Integer.parseInt(mill1);
          mll2 = Integer.parseInt(mill2);
          g2D.setStroke(stroke);
          g2D.setPaint(Color.cyan);
          num.setSpacing(true,8);
          num.setSpacing(true,8);
          if(hr1==0&hr2==0){
               num.drawNumber(1,g2D);
               num.setLocation(40,10);
               num.drawNumber(2,g2D);
          else{
               if(!(hr1 == 0)){
                    num.drawNumber(hr1,g2D);
               num.setLocation(40,10);
               num.drawNumber(hr2,g2D);
          num.setLocation(70,10);
          num.drawNumber(DigitalNumber.DOTS,g2D);
          num.setLocation(100,10);
          num.drawNumber(min1,g2D);
          num.setLocation(130,10);
          num.drawNumber(min2,g2D);
          num.setLocation(160,10);
          num.drawNumber(DigitalNumber.DOTS,g2D);
          num.setLocation(190,10);
          num.drawNumber(sec1,g2D);
          num.setLocation(220,10);
          num.drawNumber(sec2,g2D);
          /*num.setLocation(250,10);
          num.drawNumber(DigitalNumber.DOTS,g2D);
          num.setLocation(280,10);
          num.drawNumber(mll1,g2D);
          num.setLocation(310,10);
          num.drawNumber(mll2,g2D);
          g2D.setPaint(Color.cyan);
          if((c.get(Calendar.AM_PM))==Calendar.AM){
               g2D.drawString("AM",260,20);
          }else{
               g2D.drawString("PM",260,20);
     String dayOfweek = "";
     switch(c.get(Calendar.DAY_OF_WEEK)){
          case(Calendar.SUNDAY):
               dayOfweek = "Sunday, ";
               break;
          case(Calendar.MONDAY):
               dayOfweek = "Monday, ";
               break;
          case(Calendar.TUESDAY):
               dayOfweek = "Tuesday, ";
               break;
          case(Calendar.WEDNESDAY):
               dayOfweek = "Wednesday, ";
               break;
          case(Calendar.THURSDAY):
               dayOfweek = "Thursday, ";
               break;
          case(Calendar.FRIDAY):
               dayOfweek = "Friday, ";
               break;
          case(Calendar.SATURDAY):
               dayOfweek = "Saturday, ";
               break;
     String month = "";
     switch(c.get(Calendar.MONTH)){
          case(Calendar.JANUARY):
               month = "January ";
               break;
          case(Calendar.FEBRUARY):
               month = "February ";
               break;
          case(Calendar.MARCH):
               month = "March ";
               break;
          case(Calendar.APRIL):
               month = "April ";
               break;
          case(Calendar.MAY):
               month = "May ";
               break;
          case(Calendar.JUNE):
               month = "June ";
               break;
          case(Calendar.JULY):
               month = "July ";
               break;
          case(Calendar.AUGUST):
               month = "August ";
               break;
          case(Calendar.SEPTEMBER):
               month = "September ";
               break;
          case(Calendar.OCTOBER):
               month = "October ";
               break;
          case(Calendar.NOVEMBER):
               month = "November ";
               break;
          case(Calendar.DECEMBER):
               month = "December ";
               break;
     int day = c.get(Calendar.DAY_OF_MONTH);
     int year = c.get(Calendar.YEAR);
     Font font = new Font("serif",Font.PLAIN,24);
     g2D.setFont(font);
     g2D.drawString(dayOfweek+month+day+", "+year,10,80);
     public static void main(String args[]){
          AppFrame aframe = new AppFrame("Digital Clock");
          Container cpane = aframe.getContentPane();
          final DigitalClock dc = new DigitalClock();
          dc.setBackground(Color.black);
          cpane.add(dc,BorderLayout.CENTER);
          aframe.setSize(310,120);
          aframe.setVisible(true);
          class Task extends TimerTask {
             public void run() {
                  dc.repaint();
          java.util.Timer timer = new java.util.Timer();
         timer.schedule(new Task(),0L,250L);
class DigitalNumber {
     private float x=0;
     private float y=0;
     private float size=5;
     private int number;
     private Shape s;
     private float space = 0;
     public static final int DOTS = 10;
     private Color on,off;
     DigitalNumber(){
          this(0f,0f,5f,Color.cyan,Color.black);
     DigitalNumber(float x,float y, float size,Color on,Color off){
          this.x = x;
          this.y = y;
          this.size = size;
          this.on = on;
          this.off = off;
     public void drawNumber(int number,Graphics2D g){
          int flag = 0;
          switch(number){
               case(0):
                    flag = 125;
                    break;
               case(1):
                    flag = 96;
                    break;
               case(2):
                    flag = 55;
                    break;
               case(3):
                    flag = 103;
                    break;
               case(4):
                    flag = 106;
                    break;
               case(5):
                    flag = 79;
                    break;
               case(6):
                    flag = 94;
                    break;
               case(7):
                    flag = 97;
                    break;
               case(8):
                    flag = 127;
                    break;
               case(9):
                    flag = 107;
                    break;
               case(DOTS):
                    GeneralPath path = new GeneralPath();
                    path.moveTo(x+(size/2),y+(size/2)-1);
                    path.lineTo(x+(size/2),y+(size/2)+1);
                    path.moveTo(x+(size/2),y+(size/2)+size-1);
                    path.lineTo(x+(size/2),y+(size/2)+size+1);
                    g.setPaint(on);
                    g.draw(path);
                    return;
          //Top
          if((flag & 1) == 1){
               g.setPaint(on);
          }else{
               g.setPaint(off);
          GeneralPath Top = new GeneralPath();
          Top.moveTo(x + space, y);
          Top.lineTo(x + size - space, y);
          g.draw(Top);
          //Middle
          if((flag & 2) == 2){
               g.setPaint(on);
          }else{
               g.setPaint(off);
          GeneralPath Middle = new GeneralPath();
          Middle.moveTo(x + space, y + size);
          Middle.lineTo(x + size - space,y + size);
          g.draw(Middle);
          //Bottom
          if((flag & 4) == 4){
               g.setPaint(on);
          }else{
               g.setPaint(off);
          GeneralPath Bottom = new GeneralPath();
          Bottom.moveTo(x + space, y + (size * 2));
          Bottom.lineTo(x + size - space, y + (size * 2));
          g.draw(Bottom);
          //TopLeft
          if((flag & 8) == 8){
               g.setPaint(on);
          }else{
               g.setPaint(off);
          GeneralPath TopLeft = new GeneralPath();
          TopLeft.moveTo(x, y + space);
          TopLeft.lineTo(x, y + size - space);
          g.draw(TopLeft);
          //BottomLeft
          if((flag & 16) == 16){
               g.setPaint(on);
          }else{
               g.setPaint(off);
          GeneralPath BottomLeft = new GeneralPath();
          BottomLeft.moveTo(x, y + size + space);
          BottomLeft.lineTo(x, y + (size * 2) - space);
          g.draw(BottomLeft);
          //TopRight
          if((flag & 32) == 32){
               g.setPaint(on);
          }else{
               g.setPaint(off);
          GeneralPath TopRight = new GeneralPath();
          TopRight.moveTo(x + size, y + space);
          TopRight.lineTo(x + size, y + size - space);
          g.draw(TopRight);
          //BottomRight
          if((flag & 64) == 64){
               g.setPaint(on);
          }else{
               g.setPaint(off);
          GeneralPath BottomRight = new GeneralPath();
          BottomRight.moveTo(x + size, y + size + space);
          BottomRight.lineTo(x + size, y + (size * 2) - space);
          g.draw(BottomRight);
     public void setSpacing(boolean spacingOn){
          if(spacingOn == false){
               space = 0;
          else{
               this.setSpacing(spacingOn,5f);
     public void setSpacing(boolean spacingOn,float gap){
          if(gap<2){
               gap = 2;
          if(spacingOn == true){
               space = size/gap;
     public void setLocation(float x,float y){
          this.x = x;
          this.y = y;
     public void setSize(float size){
          this.size = size;
class AppFrame extends JFrame{
     AppFrame(){
          this("Demo Frame");
     AppFrame(String title){
          super(title);
          setSize(500,500);
          setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
}

Invoking a Java swing application via its process id

I have a Java swing application. What i am trying to do here is that when the user double-clicks the jar file to open it, if the Swing application is already open and is minimized, I need to maximize the open window and make it active.
I tried using 'jps -l' command in my new instance, and with the help of Runtime.exec() am able to detect whether the application is already running or not, and if running, am able to get the process id and am displaying a message to user indicating the window is already open.
But how do i maximize the window of an already running application? Is it possible?

user13333704 wrote:
I have a Java swing application. What i am trying to do here is that when the user double-clicks the jar file to open it, if the Swing application is already open and is minimized, I need to maximize the open window and make it active. That's not hard to do, but your proposed solution is hard to do. The usual way to have only one instance of a Java application running is this:
Have the application open a SocketServer on a certain port number. Since only one process can listen on a port, the second instance of the application will fail when it tries to open the SocketServer. When that happens, the second instance should terminate instead of displaying its own GUI. Whether it terminates silently or whether it displays a dialog is up to you.
If you want the second instance to communicate with the first instance, that's easy because the first instance is listening on the port. So the second instance could connect to that port and send a message to it. In your case the first instance would respond to that message by maximizing its GUI.

Unicode characters with accents won't display in Java Swing applications

I'm using FreeMind (a Java Swing application) and I need to enter classical Greek characters with accent marks. When I type an accented Greek character, FreeMind displays the unaccented character. However, I can type the accented character in MS Word, then copy and paste into FreeMind, the accented character appears.
One of the FreeMind developers indicated this was a Java Swing issue, not FreeMind, and suggested I test with another Swing application. So, I installed jEdit and got exactly the same results. I can paste an accented character into jEdit, but I cannot type it in directly.
I'm using Windows Vista with Java 6 Update 22 (build 1.6.0_22-b04). I also tested on a XP Pro box with Java 1.6.0_18-b07 and got the same result.
One other note: A couple days ago, I was able to type accented Greek characters into FreeMind. But it only worked for a couple days and then the behavior reverted to unaccented characters. It is possible, but I don't recall specifically, that I updated Java during the time and that may indicate a bug in one version of Java but not another.
Any assistance or guidance would be greatly appreciated!
Darin

Walter,
The link you provided does not appear to describe the Greek Polytonic keyboard. (The page also describes using the "Option" key as the dead key. There is no "Option" key on my keyboard. I'm using a Sony VGN-NS140E purchased in Chicago, i.e. standard physical US keyboard.)
Please see http://darindavis.net/languages/keyboard_Greek.pdf for a detailed description of how to use the Greek (Polytonic) keyboard in Windows to produce a complete set of accented classical Greek characters. This method works in MS Word and Notepad. I enabled the Greek (Polytonic) keyboard with:
Windows (Vista) Start > Control Panel > Regional and Language Options > Change Keyboards > General > Add > Greek (Greece) > Greek Polytonic
A test that will demonstrate whether you can replicate the error is to do the following in both MS Word (or Notepad) and jEdit (or FreeMind):
1. Enable the Greek Polytonic keyboard
2. Type "\" then "e" which should produce an epsilon with smooth breathing and grave accent (ἒ)
When I do this in MS Word or Notepad, I see the epsilon with smooth breathing and grave accent. When I do this in jEdit and FreeMind, I only see an epsilon.
I recorded a screencast to illustrate the problem: http://www.screencast.com/t/TRKkKQrCgbN
Actually, this problem is transient. Sometimes FreeMind or jEdit will display accented characters, other times it won't. Ironically, the first time I recorded the above referenced screencast, a few characters in jEdit did appear with accents. A couple minutes later, I re-recorded the screencast and as you can see jEdit did not display the accents. Between the two recordings I literally did nothing other than stop the Jing recording and start a new one. There is another variable at play here and I can't determine what it is. The most likely source seems to be Java since MS Word and Notepad consistently display accent characters.
Thanks,
Darin

Viewing and printing a PDF file from Java Swing Application

Hello,
I need to view and print PDF files from Java Swing Application.How do I do that?I appreciate your help.
Thank you
Sumana Somareddy

If you have a link to the URL pointing to the PDF file, you can allow the browser to open it. Then use the print function of the browser to print the PDF document.
Regards,
Tak.

Accelarate the Linux ATI Graphics card for java Swing application

Hi All,
I am using a ATI Radeon 9550 Graphic card in LFS (Linux from the scratch) environment. I want to enable the OpenGL-based pipeline for Java Swing application. I tried the -Dsun.java2d.opengl=true . But the Java swing application getting very slow.
How to overcome this problem?
Any one give the procedure to Accelerate ATI graphics card for Java Swing Application
How to verify Java swing use ATI graphics card ?
Thanks in advance..
Prabhu.S

Hi All,
I am using a ATI Radeon 9550 Graphic card in LFS (Linux from the scratch) environment. I want to enable the OpenGL-based pipeline for Java Swing application. I tried the -Dsun.java2d.opengl=true . But the Java swing application getting very slow.
How to overcome this problem?
Any one give the procedure to Accelerate ATI graphics card for Java Swing Application
How to verify Java swing use ATI graphics card ?
Thanks in advance..
Prabhu.S

UI problem when run java swing application on MAC OSX

Hello,
I have problem when i run my java swing application on MAC OSX.
Dialog box is not properly visible in MAC means ita size increses.
its size incresed and and some content or buttons on that dialog are not fully visible.
I can only see partial message or button.
If any one have idea about this problem then give the solution.
Thanks :)
Shweta

I am using following way to create dialog
JOptionPane optionpane = new JOptionPane(new Object[]{lblMsgUp}, JOptionPane.OK_CANCEL_OPTION, JOptionPane.INFORMATION_MESSAGE, null, choices, "Save");
JDialog dialog = optionpane.createDialog(parent, "Save");
dialog.setSize(450, 125);
dialog.setVisible(true);

How to load a text file in a Java swings application

hi,
I am trying to retrieve a Java code(or say any text from an existing file) and display it in a swing application.
I am not able to do so.
Please help me.

public String readFile(File f){
          try {
               BufferedReader read = new BufferedReader(new FileReader(f));
               String line = read.readLine();
               String total = "";
               while(line != null){
          //          System.out.println(line);
                    total += line;
                    line = read.readLine();
               read.close();
               return total;
          } catch (Exception e){
               e.printStackTrace();
          return "";
     }that will read a file into a string, i hope you can figure out the rest

Entry points for integrating Openoffice writer into Java swing application

I googled the web and also took a look in below 2 web sites, just seems it is very difficult to get an entry point for me to try my frist application with open office writer integrated with my swing application.
http://wiki.services.openoffice.org/wiki/Documentation/DevGuide/OpenOffice.org_Developers_Guide
http://api.openoffice.org/
What my question is:
1. Where can I get the completed jar files for using the open office writer api for my java application?
2. Is there any step by step practical example for using the api? It seems that the above links are quite messy and difficult to find an entry point to get a start, but just contain many segments separated through out the web site.
Thanks much for any suggestion.

Information regarding OOo is not on Sun websites, or in these forums. There may be 3rd-party sites that have some info regarding OOo use.

Java Swing application problem in Windows vista

When we execute the Swing application in windows vista environment.
The look and feel of the swing components are displayed improperly.
Do we need to put any specific look and feel for windows vista environment or any specific hardware configuration is required to setup windows vista environment.
Please give some inputs to solve the problem.
We have tried with the following sample code to run in windows vista.
* Vista.java
* Created on December 5, 2006, 5:39 PM
public class Vista extends javax.swing.JFrame {
/** Creates new form Vista */
public Vista() {
initComponents();
pack();
/** This method is called from within the constructor to
* initialize the form.
* WARNING: Do NOT modify this code. The content of this method is
* always regenerated by the Form Editor.
// <editor-fold defaultstate="collapsed" desc=" Generated Code ">//GEN-BEGIN:initComponents
private void initComponents() {
jButton1 = new javax.swing.JButton();
jToggleButton1 = new javax.swing.JToggleButton();
jPanel1 = new javax.swing.JPanel();
jCheckBox1 = new javax.swing.JCheckBox();
jScrollPane1 = new javax.swing.JScrollPane();
jTextArea1 = new javax.swing.JTextArea();
jTextField1 = new javax.swing.JTextField();
getContentPane().setLayout(null);
setDefaultCloseOperation(javax.swing.WindowConstants.EXIT_ON_CLOSE);
jButton1.setText("Button 1");
getContentPane().add(jButton1);
jButton1.setBounds(20, 20, 170, 30);
jToggleButton1.setText("Togle btn");
getContentPane().add(jToggleButton1);
jToggleButton1.setBounds(100, 80, 90, 20);
jPanel1.setLayout(null);
jCheckBox1.setText("jCheckBox1");
jCheckBox1.setBorder(javax.swing.BorderFactory.createEmptyBorder(0, 0, 0, 0));
jCheckBox1.setMargin(new java.awt.Insets(0, 0, 0, 0));
jPanel1.add(jCheckBox1);
jCheckBox1.setBounds(10, 40, 130, 13);
getContentPane().add(jPanel1);
jPanel1.setBounds(10, 150, 200, 130);
jTextArea1.setColumns(20);
jTextArea1.setRows(5);
jScrollPane1.setViewportView(jTextArea1);
getContentPane().add(jScrollPane1);
jScrollPane1.setBounds(210, 150, 164, 94);
jTextField1.setText("jTextField1");
getContentPane().add(jTextField1);
jTextField1.setBounds(240, 30, 140, 30);
pack();
}// </editor-fold>//GEN-END:initComponents
* @param args the command line arguments
public static void main(String args[]) {
java.awt.EventQueue.invokeLater(new Runnable() {
public void run() {
new Vista().setVisible(true);
// Variables declaration - do not modify//GEN-BEGIN:variables
private javax.swing.JButton jButton1;
private javax.swing.JCheckBox jCheckBox1;
private javax.swing.JPanel jPanel1;
private javax.swing.JScrollPane jScrollPane1;
private javax.swing.JTextArea jTextArea1;
private javax.swing.JTextField jTextField1;
private javax.swing.JToggleButton jToggleButton1;
// End of variables declaration//GEN-END:variables
}

When we execute the Swing application in windows
vista environment.
The look and feel of the swing components are
displayed improperly.Improperly means what? You must be aware that Vista's native L&F certainly isn't supported yet.

Memory leak with Swing application

My application uses more and more memory as I use it. However, if it is working like I think, it is not creating more objects and has no reason to use more memory. When the application is minimized a lot of that memory is freed up. Does anyone know what is the cause of this? I have a sneaking suspicion that it is somehow related to my swingworkers. Also, if it is an error with my code how do I use the netbeans profiler to find the cause? I have just used the profiler for the first time - all I really can tell is that it seems to consume more and more memory.

To answer a comment earlier in this thread, of course
the jvm is doing garbage collection - that's the way
java works. Nobody said otherwise. What was said was that the JVM doesn't necessarily release the memory. Just because the object has been collected doesn't mean the JVM is going to give it back to the OS.
As I understand, when you do System.gc()
this is apparently just a hint to the jvm to do
garbage collection. To quote the api:
"Calling the gc method suggests that the Java
Virtual Machine expend effort toward recycling
unused objects in order to make the memory they
currently occupy available for quick reuse."Which is irrelevant. Furthermore, this thread is almost a year old.

Design Patterns for java swing application front a J2EE server

Hi,
i dont nkow that i stay in the correct forum. I am development a java swing client application, no web, and i dont know that if there are any patterns for a client of this type.
I have readed http://java.sun.com/blueprints/corej2eepatterns/Patterns/index.html
but after of Buissnes Delegate pattern, the others one, over ejb tier, are applicated only for web clients, using servlets and jsp pages.
If i have a swing client application, what patterns i must folow for implement the client logic of my swing application??
thanks

MVC pattern is one of the most used
http://en.wikipedia.org/wiki/MVC
http://csis.pace.edu/~bergin/mvc/mvcgui.html
...

How to invoke a JAR from Java Swing application?

Hi,
I am trying to start a jar file from the swings application.
I am trying the following code,
String cmd[] = new String[]{"cmd", "java -jar TestJFreeChart.jar"};
try
Process run = Runtime.getRuntime().exec(cmd);
catch(Exception e)
{}Is anything wrong in the usage?

First try:
"cmd /c java -jar app.jar" or cmd start, because it can't jsut run java.exe, it needs to be
passed to the cmd interpretor witch further calls java.exe, etc
Also read what stevejluke suggested. Its important to know if .waitFor or not.
You wont understand these until you read the tutorial.

How use system.out.println with a Java Swing Applet?

Hi guys,
I was just wondering what can I use to view output on the Java console with a Java Swing Applet?
At the moment I'm using a JTextArea within the Applet for debugging but I want output to appear in the browser java console but system.out.println doesn't work.
I'm viewing the Swing Applet on Netscape 4.7 browser.
Any ideas?

System.out.println()s work fine! I'm guessing that your problem is that you are looking at the wrong console window!
You're using the Java Plug-in, right? On Windows, go to your Control Panel and double click "Java Plug-in". You should find a checkbox option to "Show Java Console" - make sure this is checked. Next time you fire up you JApplet, you should see a Java Console window popup.
Hope this helps!

Out of memory in java swing application

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