Java - Server with Multiple Clients Error

Java - Server with Multiple Clients Error - java

I'm new to the concept of creating a server and multiple clients using Java, so apologies if this is an obvious fix. I've been trying to code a jframe chat program that has a server and two clients, which currently are all using the same port. Whatever data is sent by client one will be passed to the server, which will display it. So far, the code does this, however, I also want to pass said data to the other client. I'm trying to code the program so that I can specify the client the data is sent to.
The code follows as:
Server Code.
package Chats;
import java.io.*;
import java.net.*;
public class Chat_Server extends javax.swing.JFrame
{
static ServerSocket ss;
static Socket s;
static DataInputStream din;
static DataOutputStream dout;
public Chat_Server()
{
initComponents();
}
#SuppressWarnings("unchecked")
// <editor-fold defaultstate="collapsed" desc="Generated Code">
private void initComponents() {
jScrollPane1 = new javax.swing.JScrollPane();
Msg_Area = new javax.swing.JTextArea();
setDefaultCloseOperation(javax.swing.WindowConstants.EXIT_ON_CLOSE);
Msg_Area.setColumns(20);
Msg_Area.setRows(5);
jScrollPane1.setViewportView(Msg_Area);
javax.swing.GroupLayout layout = new javax.swing.GroupLayout(getContentPane());
getContentPane().setLayout(layout);
layout.setHorizontalGroup(
layout.createParallelGroup(javax.swing.GroupLayout.Alignment.LEADING)
.addGroup(layout.createSequentialGroup()
.addGap(32, 32, 32)
.addComponent(jScrollPane1, javax.swing.GroupLayout.PREFERRED_SIZE, 332, javax.swing.GroupLayout.PREFERRED_SIZE)
.addContainerGap(36, Short.MAX_VALUE))
);
layout.setVerticalGroup(
layout.createParallelGroup(javax.swing.GroupLayout.Alignment.LEADING)
.addGroup(layout.createSequentialGroup()
.addGap(24, 24, 24)
.addComponent(jScrollPane1, javax.swing.GroupLayout.PREFERRED_SIZE, 237, javax.swing.GroupLayout.PREFERRED_SIZE)
.addContainerGap(39, Short.MAX_VALUE))
);
pack();
}// </editor-fold>
public static void main(String args[])
{
/* Set the Nimbus look and feel */
//<editor-fold defaultstate="collapsed" desc=" Look and feel setting code (optional) ">
/* If Nimbus (introduced in Java SE 6) is not available, stay with the default look and feel.
* For details see http://download.oracle.com/javase/tutorial/uiswing/lookandfeel/plaf.html
*/
try {
for (javax.swing.UIManager.LookAndFeelInfo info : javax.swing.UIManager.getInstalledLookAndFeels()) {
if ("Nimbus".equals(info.getName())) {
javax.swing.UIManager.setLookAndFeel(info.getClassName());
break;
}
}
} catch (ClassNotFoundException ex) {
java.util.logging.Logger.getLogger(Chat_Server.class.getName()).log(java.util.logging.Level.SEVERE, null, ex);
} catch (InstantiationException ex) {
java.util.logging.Logger.getLogger(Chat_Server.class.getName()).log(java.util.logging.Level.SEVERE, null, ex);
} catch (IllegalAccessException ex) {
java.util.logging.Logger.getLogger(Chat_Server.class.getName()).log(java.util.logging.Level.SEVERE, null, ex);
} catch (javax.swing.UnsupportedLookAndFeelException ex) {
java.util.logging.Logger.getLogger(Chat_Server.class.getName()).log(java.util.logging.Level.SEVERE, null, ex);
}
//</editor-fold>
java.awt.EventQueue.invokeLater(new Runnable()
{
public void run()
{
new Chat_Server().setVisible(true);
}
});
String msgin = "";
try
{
ss = new ServerSocket(1201); // Server starts at 1201 port number
s = ss.accept(); // Now server will accept the connections.
din = new DataInputStream(s.getInputStream());
dout = new DataOutputStream(s.getOutputStream());
while(!msgin.equals("exit"))
{
msgin = din.readUTF();
Msg_Area.setText(Msg_Area.getText().trim() + "\n Client: \t" + msgin); // Displaying the message from client
}
}
catch(Exception e)
{
}
}
// Variables declaration - do not modify
private static javax.swing.JTextArea Msg_Area;
private javax.swing.JScrollPane jScrollPane1;
// End of variables declaration
}
Client Code.
package Chats;
import java.io.DataInputStream;
import java.io.DataOutputStream;
import java.net.Socket;
public class Chat_Client extends javax.swing.JFrame
{
static Socket s;
static DataInputStream din;
static DataOutputStream dout;
public Chat_Client()
{
initComponents();
}
#SuppressWarnings("unchecked")
// <editor-fold defaultstate="collapsed" desc="Generated Code">
private void initComponents() {
Msg_Text = new javax.swing.JTextField();
jScrollPane1 = new javax.swing.JScrollPane();
Msg_Area = new javax.swing.JTextArea();
Msg_Send = new javax.swing.JButton();
setDefaultCloseOperation(javax.swing.WindowConstants.EXIT_ON_CLOSE);
Msg_Text.setText("jTextField1");
Msg_Area.setColumns(20);
Msg_Area.setRows(5);
jScrollPane1.setViewportView(Msg_Area);
Msg_Send.setText("jButton1");
Msg_Send.addActionListener(new java.awt.event.ActionListener() {
public void actionPerformed(java.awt.event.ActionEvent evt) {
Msg_SendActionPerformed(evt);
}
});
javax.swing.GroupLayout layout = new javax.swing.GroupLayout(getContentPane());
getContentPane().setLayout(layout);
layout.setHorizontalGroup(
layout.createParallelGroup(javax.swing.GroupLayout.Alignment.LEADING)
.addGroup(layout.createSequentialGroup()
.addGap(29, 29, 29)
.addGroup(layout.createParallelGroup(javax.swing.GroupLayout.Alignment.LEADING)
.addComponent(jScrollPane1, javax.swing.GroupLayout.PREFERRED_SIZE, 332, javax.swing.GroupLayout.PREFERRED_SIZE)
.addGroup(layout.createSequentialGroup()
.addComponent(Msg_Text, javax.swing.GroupLayout.PREFERRED_SIZE, 257, javax.swing.GroupLayout.PREFERRED_SIZE)
.addPreferredGap(javax.swing.LayoutStyle.ComponentPlacement.RELATED, 31, Short.MAX_VALUE)
.addComponent(Msg_Send)))
.addContainerGap())
);
layout.setVerticalGroup(
layout.createParallelGroup(javax.swing.GroupLayout.Alignment.LEADING)
.addGroup(javax.swing.GroupLayout.Alignment.TRAILING, layout.createSequentialGroup()
.addGap(19, 19, 19)
.addComponent(jScrollPane1, javax.swing.GroupLayout.PREFERRED_SIZE, 196, javax.swing.GroupLayout.PREFERRED_SIZE)
.addPreferredGap(javax.swing.LayoutStyle.ComponentPlacement.RELATED, 31, Short.MAX_VALUE)
.addGroup(layout.createParallelGroup(javax.swing.GroupLayout.Alignment.BASELINE)
.addComponent(Msg_Text, javax.swing.GroupLayout.PREFERRED_SIZE, 31, javax.swing.GroupLayout.PREFERRED_SIZE)
.addComponent(Msg_Send))
.addGap(23, 23, 23))
);
pack();
}// </editor-fold>
private void Msg_SendActionPerformed(java.awt.event.ActionEvent evt) {
try
{
String msgout = "";
msgout = Msg_Text.getText().trim();
dout.writeUTF(msgout);
}
catch (Exception e)
{
//handle exceptions here.
}
}
public static void main(String args[])
{
/* Set the Nimbus look and feel */
//<editor-fold defaultstate="collapsed" desc=" Look and feel setting code (optional) ">
/* If Nimbus (introduced in Java SE 6) is not available, stay with the default look and feel.
* For details see http://download.oracle.com/javase/tutorial/uiswing/lookandfeel/plaf.html
*/
try {
for (javax.swing.UIManager.LookAndFeelInfo info : javax.swing.UIManager.getInstalledLookAndFeels()) {
if ("Nimbus".equals(info.getName())) {
javax.swing.UIManager.setLookAndFeel(info.getClassName());
break;
}
}
} catch (ClassNotFoundException ex) {
java.util.logging.Logger.getLogger(Chat_Client.class.getName()).log(java.util.logging.Level.SEVERE, null, ex);
} catch (InstantiationException ex) {
java.util.logging.Logger.getLogger(Chat_Client.class.getName()).log(java.util.logging.Level.SEVERE, null, ex);
} catch (IllegalAccessException ex) {
java.util.logging.Logger.getLogger(Chat_Client.class.getName()).log(java.util.logging.Level.SEVERE, null, ex);
} catch (javax.swing.UnsupportedLookAndFeelException ex) {
java.util.logging.Logger.getLogger(Chat_Client.class.getName()).log(java.util.logging.Level.SEVERE, null, ex);
}
//</editor-fold>
java.awt.EventQueue.invokeLater(new Runnable()
{
public void run()
{
new Chat_Client().setVisible(true);
}
});
try
{
s = new Socket ("127.0.0.1", 1201); // Here the ip ddress is local address.
din = new DataInputStream(s.getInputStream());
dout = new DataOutputStream(s.getOutputStream());
String msgin = "";
while (!msgin.equals("exit"))
{
msgin = din.readUTF();
Msg_Area.setText(Msg_Area.getText().trim() + "\n Server: \t" + msgin);
}
}
catch(Exception e)
{
//Exception Code
}
}
// Variables declaration - do not modify
private static javax.swing.JTextArea Msg_Area;
private javax.swing.JButton Msg_Send;
private javax.swing.JTextField Msg_Text;
private javax.swing.JScrollPane jScrollPane1;
// End of variables declaration
}
I have another page set up for the other client but so far the code is a carbon copy of the first client page, so there's no point posting it.

You're only accepting a single client with ss.accept() and that's it. ServerSocket#accept waits for a SINGLE incoming client connection and creates a Socket object. In order to accept multiple connections you need continuously loop ss.accept() to keep listening for other client connections. Once a new connection is made you can add it to a list. (I have not tested the code, it's more just to point you in the direction you need)
public static void main(String []args) throw Exception{
ServerSocket serverSocket = new ServerSocket(1201);
List<Socket> clients = new ArrayList<Socket>();
while(true) {//continuously listening for a new connection
Socket client = serverSocket.accept();
clients.add(client);
}
}
Now the problem with this is that if your server constantly listens for a connection it'll block your thread. So everytime a connection is added, spawn a new thread to handle it.
public static void main(String []args) throw Exception{
ServerSocket serverSocket = new ServerSocket(1201);
List<Socket> clients = new ArrayList<Socket>();
while(true) {
Socket client = serverSocket.accept();
clients.add(client);
new Thread(new Runnable(){
public void run(){
//Handle socket here
}
}).start();
}
}
If you want to avoid creating multiple threads like this, then you're gonna have to use nio socketchannels.

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Data not being disaplyed in combo box - Sql and Java using Netbeans

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// Variables declaration - do not modify
private javax.swing.JComboBox<String> combo1;
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}
The combo box still doesn't display any values from the database. Could someone please tell me what's wrong in my code?

I kept trying and finally got it! I used a function called fillCombo an then called it! It worked. This is what I love about coding, you just got to keep trying an when you finally solve it, it feels just amazing.
Now I have to solve the next problem I encountered, removing duplicate values. I'm going to keep trying!

Swing: JFormattedTextField set to numbers only using Netbeans

I've got a little problem with JFormattedTextField:
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package SerasApp;
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private void initComponents() {
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out.println("tests");
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// TODO add your handling code here:
}
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// TODO add your handling code here:
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/**
* #param args the command line arguments
*/
public static void main(String args[]) {
/* Set the Nimbus look and feel */
//<editor-fold defaultstate="collapsed" desc=" Look and feel setting code (optional) ">
/* If Nimbus (introduced in Java SE 6) is not available, stay with the default look and feel.
* For details see http://download.oracle.com/javase/tutorial/uiswing/lookandfeel/plaf.html
*/
try {
for (javax.swing.UIManager.LookAndFeelInfo info : javax.swing.UIManager.getInstalledLookAndFeels()) {
if ("Nimbus".equals(info.getName())) {
javax.swing.UIManager.setLookAndFeel(info.getClassName());
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java.util.logging.Logger.getLogger(Main.class.getName()).log(java.util.logging.Level.SEVERE, null, ex);
} catch (InstantiationException ex) {
java.util.logging.Logger.getLogger(Main.class.getName()).log(java.util.logging.Level.SEVERE, null, ex);
} catch (IllegalAccessException ex) {
java.util.logging.Logger.getLogger(Main.class.getName()).log(java.util.logging.Level.SEVERE, null, ex);
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java.util.logging.Logger.getLogger(Main.class.getName()).log(java.util.logging.Level.SEVERE, null, ex);
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/* Create and display the form */
java.awt.EventQueue.invokeLater(new Runnable() {
public void run() {
new Main().setVisible(true);
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// Variables declaration - do not modify
private javax.swing.JLabel HiSera;
private javax.swing.JPanel Intro;
private javax.swing.JPanel MainDisplayFrame;
private javax.swing.JPanel MainMenu;
private javax.swing.JPanel WeatherOptions;
private javax.swing.JFormattedTextField humidityLevel;
private javax.swing.JButton jButton2;
private javax.swing.JButton jButton3;
private javax.swing.JLabel jLabel1;
private javax.swing.JButton sunny;
// End of variables declaration
}
I've tried also to set a humidityLevel to new formatted text field to no avail.
Mainly it's this bit of code:
public void HumidityLevel()
{
NumberFormat a = NumberFormat.getNumberInstance();
NumberFormatter b = new NumberFormatter(a);
DefaultFormatterFactory c = new DefaultFormatterFactory(b);
humidityLevel.setFormatterFactory(c);
}
and this bit:
private void formWindowGainedFocus(java.awt.event.WindowEvent evt) {
// TODO add your handling code here:
PositionHiSera();
try {
Thread.sleep(1000);
} catch (InterruptedException ex) {
Logger.getLogger(Main.class.getName()).log(Level.SEVERE, null, ex);
}
//make Intro Disappear and make Weather Options Appear
WeatherOptions.setVisible(true);
Intro.setVisible(false);
HumidityLevel();
out.println("tests");
}
I also don't want to use a JTextField because I want to learn how to use JFormattedTextField.

I want to set the formatted text fields to numbers only.
Using the Design view, right click over the formatted text field and choose Properties option. Then look for formatterFactory property:
If you try to edit this property, the following dialog will show up. Choose integer default option under number category:
That's it, your text field will be initialized using NumberFormat.getIntegerInstance(). If you inspect the generated source code you'll see something like this:
jFormattedTextField1 = new javax.swing.JFormattedTextField();
jFormattedTextField1.setFormatterFactory(new javax.swing.text.DefaultFormatterFactory(new javax.swing.text.NumberFormatter(java.text.NumberFormat.getIntegerInstance())));
Off-topic
As #mKorbel pointed out, using Thread.sleep() is a bad idea and will block the Event Dispatch Thread (EDT) which is a single and special thread where Swing components creation / update should be performed and event handling is processed. If this thread is blocked then your GUI won't be able to repaint itself and will "freeze". In this case you should consider use a Swing Timer instead. See Concurrency in Swing for further details.

Making a JFrame button create a Alert Dialog. Java - Netbeans

I use NetBeans IDE, as you may know there is a JFrame creator plugin (Its pre-installed) I use it to make JFrames (Because I'm too lazy to do it my self =/). in the event of creating a button within that JFrame it will generate a area for the event code. I was wondering what code i need to type in to generate the Alert Dialog. Heres what is pre-generated upon create a swing/awt component or a JFrame:
public class NewJFrame extends javax.swing.JFrame {
public NewJFrame() {
initComponents();
}
#SuppressWarnings("unchecked")
// <editor-fold defaultstate="collapsed" desc="Generated Code">
private void initComponents() {
jDialog2 = new javax.swing.JDialog();
jButton1 = new javax.swing.JButton();
javax.swing.GroupLayout jDialog2Layout = new javax.swing.GroupLayout(jDialog2.getContentPane());
jDialog2.getContentPane().setLayout(jDialog2Layout);
jDialog2Layout.setHorizontalGroup(
jDialog2Layout.createParallelGroup(javax.swing.GroupLayout.Alignment.LEADING)
.addGap(0, 400, Short.MAX_VALUE)
);
jDialog2Layout.setVerticalGroup(
jDialog2Layout.createParallelGroup(javax.swing.GroupLayout.Alignment.LEADING)
.addGap(0, 300, Short.MAX_VALUE)
);
setDefaultCloseOperation(javax.swing.WindowConstants.EXIT_ON_CLOSE);
setTitle(">:D");
setResizable(false);
addHierarchyBoundsListener(new java.awt.event.HierarchyBoundsListener() {
public void ancestorMoved(java.awt.event.HierarchyEvent evt) {
formAncestorMoved(evt);
}
public void ancestorResized(java.awt.event.HierarchyEvent evt) {
}
});
jButton1.setText("Press Me :D");
jButton1.addActionListener(new java.awt.event.ActionListener() {
public void actionPerformed(java.awt.event.ActionEvent evt) {
jButton1ActionPerformed(evt);
}
});
javax.swing.GroupLayout layout = new javax.swing.GroupLayout(getContentPane());
getContentPane().setLayout(layout);
layout.setHorizontalGroup(
layout.createParallelGroup(javax.swing.GroupLayout.Alignment.LEADING)
.addComponent(jButton1, javax.swing.GroupLayout.Alignment.TRAILING, javax.swing.GroupLayout.DEFAULT_SIZE, 349, Short.MAX_VALUE)
);
layout.setVerticalGroup(
layout.createParallelGroup(javax.swing.GroupLayout.Alignment.LEADING)
.addComponent(jButton1, javax.swing.GroupLayout.Alignment.TRAILING, javax.swing.GroupLayout.DEFAULT_SIZE, 180, Short.MAX_VALUE)
);
pack();
setLocationRelativeTo(null);
}// </editor-fold>
private void jButton1ActionPerformed(java.awt.event.ActionEvent evt) {
//This is the area for the code dialog code
}
private void formAncestorMoved(java.awt.event.HierarchyEvent evt) {
// TODO add your handling code here:
}
/**
* #param args the command line arguments
*/
public static void main(String args[]) {
/* Set the Nimbus look and feel */
//<editor-fold defaultstate="collapsed" desc=" Look and feel setting code (optional) ">
/* If Nimbus (introduced in Java SE 6) is not available, stay with the default look and feel.
* For details see http://download.oracle.com/javase/tutorial/uiswing/lookandfeel/plaf.html
*/
try {
for (javax.swing.UIManager.LookAndFeelInfo info : javax.swing.UIManager.getInstalledLookAndFeels()) {
if ("Nimbus".equals(info.getName())) {
javax.swing.UIManager.setLookAndFeel(info.getClassName());
break;
}
}
} catch (ClassNotFoundException ex) {
java.util.logging.Logger.getLogger(NewJFrame.class.getName()).log(java.util.logging.Level.SEVERE, null, ex);
} catch (InstantiationException ex) {
java.util.logging.Logger.getLogger(NewJFrame.class.getName()).log(java.util.logging.Level.SEVERE, null, ex);
} catch (IllegalAccessException ex) {
java.util.logging.Logger.getLogger(NewJFrame.class.getName()).log(java.util.logging.Level.SEVERE, null, ex);
} catch (javax.swing.UnsupportedLookAndFeelException ex) {
java.util.logging.Logger.getLogger(NewJFrame.class.getName()).log(java.util.logging.Level.SEVERE, null, ex);
}
//</editor-fold>
/* Create and display the form */
java.awt.EventQueue.invokeLater(new Runnable() {
public void run() {
new NewJFrame().setVisible(true);
}
});
}
Did you see the Button1ActionPerformed thing????
that's where the code goes.
I need code that will create a new Alert Dialog (javax.swing.JDialog)
When that is pressed.
Thanks in advance

Sounds like you might want a JOptionPane message dialog...
Try this:
JOptionPane.showMessageDialog(null, "<your message here...>", "Alert", JOptionPane.ERROR_MESSAGE);
So for your case, this is what your action performed method will look like:
private void jButton1ActionPerformed(java.awt.event.ActionEvent evt) {
JOptionPane.showMessageDialog(null, "<your message here...>", "Alert", JOptionPane.ERROR_MESSAGE);
}
Note there is no "variable" to store the JOptionPane object, it's a static method called on the JOptionPane class. Each time you want an alert/confirm/input/etc. dialog, you generate one on the fly using the static members of the JOptionPane class.
See the reference for more info...

This is what i see
public class NewJFrame extends javax.swing.JFrame {
/**
* Creates new form NewJFrame
*/
public NewJFrame() {
initComponents();
}
/**
* 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.
*/
#SuppressWarnings("unchecked")
// <editor-fold defaultstate="collapsed" desc="Generated Code">
private void initComponents() {
jOptionPane1 = new javax.swing.JOptionPane();
jButton1 = new javax.swing.JButton();
setDefaultCloseOperation(javax.swing.WindowConstants.EXIT_ON_CLOSE);
setTitle(">:D");
setResizable(false);
addHierarchyBoundsListener(new java.awt.event.HierarchyBoundsListener() {
public void ancestorMoved(java.awt.event.HierarchyEvent evt) {
formAncestorMoved(evt);
}
public void ancestorResized(java.awt.event.HierarchyEvent evt) {
}
});
jButton1.setText("Press Me :D");
jButton1.addActionListener(new java.awt.event.ActionListener() {
public void actionPerformed(java.awt.event.ActionEvent evt) {
jButton1ActionPerformed(evt);
}
});
javax.swing.GroupLayout layout = new javax.swing.GroupLayout(getContentPane());
getContentPane().setLayout(layout);
layout.setHorizontalGroup(
layout.createParallelGroup(javax.swing.GroupLayout.Alignment.LEADING)
.addComponent(jButton1, javax.swing.GroupLayout.PREFERRED_SIZE, 353, javax.swing.GroupLayout.PREFERRED_SIZE)
.addGroup(layout.createParallelGroup(javax.swing.GroupLayout.Alignment.LEADING)
.addGroup(layout.createSequentialGroup()
.addGap(0, 45, Short.MAX_VALUE)
.addComponent(jOptionPane1, javax.swing.GroupLayout.PREFERRED_SIZE, javax.swing.GroupLayout.DEFAULT_SIZE, javax.swing.GroupLayout.PREFERRED_SIZE)
.addGap(0, 46, Short.MAX_VALUE)))
);
layout.setVerticalGroup(
layout.createParallelGroup(javax.swing.GroupLayout.Alignment.LEADING)
.addComponent(jButton1, javax.swing.GroupLayout.Alignment.TRAILING, javax.swing.GroupLayout.DEFAULT_SIZE, 180, Short.MAX_VALUE)
.addGroup(layout.createParallelGroup(javax.swing.GroupLayout.Alignment.LEADING)
.addGroup(layout.createSequentialGroup()
.addGap(0, 0, Short.MAX_VALUE)
.addComponent(jOptionPane1, javax.swing.GroupLayout.PREFERRED_SIZE, javax.swing.GroupLayout.DEFAULT_SIZE, javax.swing.GroupLayout.PREFERRED_SIZE)
.addGap(0, 0, Short.MAX_VALUE)))
);
pack();
setLocationRelativeTo(null);
}// </editor-fold>
private void jButton1ActionPerformed(java.awt.event.ActionEvent evt) {
//jOptionPane.showMessageDialog(null, "<your message here...>", "Alert", jOptionPane.ERROR_MESSAGE);
}
private void formAncestorMoved(java.awt.event.HierarchyEvent evt) {
// TODO add your handling code here:
}
/**
* #param args the command line arguments
*/
public static void main(String args[]) {
/* Set the Nimbus look and feel */
//<editor-fold defaultstate="collapsed" desc=" Look and feel setting code (optional) ">
/* If Nimbus (introduced in Java SE 6) is not available, stay with the default look and feel.
* For details see http://download.oracle.com/javase/tutorial/uiswing/lookandfeel/plaf.html
*/
try {
for (javax.swing.UIManager.LookAndFeelInfo info : javax.swing.UIManager.getInstalledLookAndFeels()) {
if ("Nimbus".equals(info.getName())) {
javax.swing.UIManager.setLookAndFeel(info.getClassName());
break;
}
}
} catch (ClassNotFoundException ex) {
java.util.logging.Logger.getLogger(NewJFrame.class.getName()).log(java.util.logging.Level.SEVERE, null, ex);
} catch (InstantiationException ex) {
java.util.logging.Logger.getLogger(NewJFrame.class.getName()).log(java.util.logging.Level.SEVERE, null, ex);
} catch (IllegalAccessException ex) {
java.util.logging.Logger.getLogger(NewJFrame.class.getName()).log(java.util.logging.Level.SEVERE, null, ex);
} catch (javax.swing.UnsupportedLookAndFeelException ex) {
java.util.logging.Logger.getLogger(NewJFrame.class.getName()).log(java.util.logging.Level.SEVERE, null, ex);
}
//</editor-fold>
/* Create and display the form */
java.awt.EventQueue.invokeLater(new Runnable() {
public void run() {
new NewJFrame().setVisible(true);
}
});
}
// Variables declaration - do not modify
private javax.swing.JButton jButton1;
private javax.swing.JOptionPane jOptionPane1;
// End of variables declaration
}

Java:taking result from List selection listenner

i've some problem with my list selection listener that i show you below
1.the result of the listener printing twice that i don't have an idea about it...!??!why it's printing twice?
2.when i pressing the searchBt and the result shows,and i choose one of the result i want to return ChooseIndex from the valueChanged(ListSelectionEvent e) but it can't has a return statement and the selected index of thge j list is useless...what's the problem?
public class SearchPage extends javax.swing.JFrame {
public SearchPage() {
initComponents();
}
/**
* 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.
*/
#SuppressWarnings("unchecked")
// <editor-fold defaultstate="collapsed" desc="Generated Code">
private void initComponents() {
SearchBox = new javax.swing.JTextField();
SearchBt = new javax.swing.JButton();
jScrollPane1 = new javax.swing.JScrollPane();
jList1 = new javax.swing.JList();
setDefaultCloseOperation(javax.swing.WindowConstants.EXIT_ON_CLOSE);
SearchBt.setText("Search");
SearchBt.addActionListener(new java.awt.event.ActionListener() {
public void actionPerformed(java.awt.event.ActionEvent evt) {
SearchBtActionPerformed(evt);
}
});
jList1.setSelectionMode(javax.swing.ListSelectionModel.SINGLE_INTERVAL_SELECTION);
jList1.setToolTipText("");
jList1.setCursor(new java.awt.Cursor(java.awt.Cursor.DEFAULT_CURSOR));
jList1.setSelectionBackground(new java.awt.Color(102, 0, 102));
jList1.setValueIsAdjusting(true);
jList1.setVerifyInputWhenFocusTarget(false);
jScrollPane1.setViewportView(jList1);
jList1.getAccessibleContext().setAccessibleName("");
javax.swing.GroupLayout layout = new javax.swing.GroupLayout(getContentPane());
getContentPane().setLayout(layout);
layout.setHorizontalGroup(
layout.createParallelGroup(javax.swing.GroupLayout.Alignment.LEADING)
.addGroup(layout.createSequentialGroup()
.addGap(16, 16, 16)
.addGroup(layout.createParallelGroup(javax.swing.GroupLayout.Alignment.LEADING)
.addComponent(jScrollPane1, javax.swing.GroupLayout.PREFERRED_SIZE, 543, javax.swing.GroupLayout.PREFERRED_SIZE)
.addGroup(layout.createSequentialGroup()
.addComponent(SearchBox, javax.swing.GroupLayout.PREFERRED_SIZE, 244, javax.swing.GroupLayout.PREFERRED_SIZE)
.addPreferredGap(javax.swing.LayoutStyle.ComponentPlacement.UNRELATED)
.addComponent(SearchBt, javax.swing.GroupLayout.PREFERRED_SIZE, 140, javax.swing.GroupLayout.PREFERRED_SIZE)))
.addContainerGap(281, Short.MAX_VALUE))
);
layout.setVerticalGroup(
layout.createParallelGroup(javax.swing.GroupLayout.Alignment.LEADING)
.addGroup(layout.createSequentialGroup()
.addGap(125, 125, 125)
.addGroup(layout.createParallelGroup(javax.swing.GroupLayout.Alignment.BASELINE)
.addComponent(SearchBox, javax.swing.GroupLayout.PREFERRED_SIZE, javax.swing.GroupLayout.DEFAULT_SIZE, javax.swing.GroupLayout.PREFERRED_SIZE)
.addComponent(SearchBt))
.addPreferredGap(javax.swing.LayoutStyle.ComponentPlacement.RELATED)
.addComponent(jScrollPane1, javax.swing.GroupLayout.DEFAULT_SIZE, 315, Short.MAX_VALUE)
.addContainerGap())
);
pack();
}// </editor-fold>
private void SearchBtActionPerformed(java.awt.event.ActionEvent evt) {
String tag = SearchBox.getText().trim();
Vector<String> vector = new Vector<String>();
for (int i = 0; i <Code.CodeSearch(tag).size(); i++) {
String string = Code.FNameExtractor(Code.CodeSearch(tag).get(i).getFileName())+" Uploaded By "+Code.CodeSearch(tag).get(i).getUserdetails().getUsername();
vector.add(string);
}
jList1 = new JList<String>(vector);
ListSelectionModel listSelectionModel = jList1.getSelectionModel();
listSelectionModel.addListSelectionListener(new SharedListSelectionHandler());
listSelectionModel.setSelectionMode(ListSelectionModel.SINGLE_SELECTION);
jScrollPane1.setViewportView(jList1);
}
/**
* #param args the command line arguments
*/
public static void main(String args[]) {
/* Set the Nimbus look and feel */
//<editor-fold defaultstate="collapsed" desc=" Look and feel setting code (optional) ">
/* If Nimbus (introduced in Java SE 6) is not available, stay with the default look and feel.
* For details see http://download.oracle.com/javase/tutorial/uiswing/lookandfeel/plaf.html
*/
try {
for (javax.swing.UIManager.LookAndFeelInfo info : javax.swing.UIManager.getInstalledLookAndFeels()) {
if ("Nimbus".equals(info.getName())) {
javax.swing.UIManager.setLookAndFeel(info.getClassName());
break;
}
}
} catch (ClassNotFoundException ex) {
java.util.logging.Logger.getLogger(SearchPage.class.getName()).log(java.util.logging.Level.SEVERE, null, ex);
} catch (InstantiationException ex) {
java.util.logging.Logger.getLogger(SearchPage.class.getName()).log(java.util.logging.Level.SEVERE, null, ex);
} catch (IllegalAccessException ex) {
java.util.logging.Logger.getLogger(SearchPage.class.getName()).log(java.util.logging.Level.SEVERE, null, ex);
} catch (javax.swing.UnsupportedLookAndFeelException ex) {
java.util.logging.Logger.getLogger(SearchPage.class.getName()).log(java.util.logging.Level.SEVERE, null, ex);
}
//</editor-fold>
/* Create and display the form */
java.awt.EventQueue.invokeLater(new Runnable() {
public void run() {
new SearchPage().setVisible(true);
}
});
}
class SharedListSelectionHandler implements ListSelectionListener {
public void valueChanged(ListSelectionEvent e) {
ListSelectionModel lsm = (ListSelectionModel)e.getSource();
int ChooseIndex =lsm.getMaxSelectionIndex();
System.out.println(ChooseIndex);
}
}
// Variables declaration - do not modify
private javax.swing.JTextField SearchBox;
private javax.swing.JButton SearchBt;
private javax.swing.JList jList1;
private javax.swing.JScrollPane jScrollPane1;
// End of variables declaration
}

The selection listener only tells us the index of the selected item. That's normal. The list doesn't care about the content. You have to store the list model (iaw, a list of strings that you actually display) somewhere and use the index value from the listener to lookup the content at the index in your model. That's the common pattern.
For the first question - I'd set a breakpoint on the print statement, debug and look at the stacktrace. Then I'd see why the method was called twice.

Suddenly: java.lang.NullPointerException, worked fine last night

I made a small program that listens and sends lines on a tcp socket and appends the received info to a JTextArea. I use this to chat on a Minecraft server without having the game open.
I was working fine last night, but when I got up it wasn't working. When I opened netbeans and ran it, it gave this error:
Exception in thread "main" java.lang.NullPointerException
at com.xxx.mcchat.chat.main(chat.java:333)
Can anyone explain what's wrong?
Here is the code (http://pastebin.com/FPNty0qf):
/*
* To change this template, choose Tools | Templates
* and open the template in the editor.
*/
package com.xxx.mcchat;
import java.io.*;
import java.net.*;
import net.sf.json.*;
import org.apache.commons.beanutils.*;
import org.apache.commons.collections.*;
import org.apache.commons.lang.*;
import net.sf.ezmorph.*;
import org.apache.commons.logging.*;
import java.awt.event.*;
import javax.swing.UIManager;
/**
*
* #author xxx
*/
public class chat extends javax.swing.JFrame {
/**
* Creates new form chat
*/
public chat() {
initComponents();
}
public void send(String user, String message){
Socket socket = null;
PrintWriter out = null;
BufferedReader in = null;
try {
socket = new Socket("mc.xxx.net", 20060);
out = new PrintWriter(socket.getOutputStream(), true);
in = new BufferedReader(new InputStreamReader(socket.getInputStream()));
} catch (UnknownHostException e) {
System.err.println("Don't know about host");
System.exit(1);
} catch (IOException e) {
System.err.println("Couldn't get I/O for the connection");
System.exit(1);
}
BufferedReader read = new BufferedReader(new InputStreamReader(System.in));
//System.out.println(in.readLine()); //Uncomment to debug
if(username != null){
out.println("/api/call?method=broadcast&args="+"[\"§7[Web] §b"+username+"§7:§f "+message+"\"]"+"&key=f0e2ad47a9a43c783d2c54f396f655c9279829c8c69ae9f52934648098dec993");
chatArea.append(username + ": " + message + "\n\r");
if(autoscrollCheck.isSelected()){
chatArea.setCaretPosition(chatArea.getText().length() - 1);
}
}else{
chatArea.append("You must set your username!!" + "\n\r");
if(autoscrollCheck.isSelected()){
chatArea.setCaretPosition(chatArea.getText().length() - 1);
}
}
}
/**
* 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.
*/
#SuppressWarnings("unchecked")
// <editor-fold defaultstate="collapsed" desc="Generated Code">
private void initComponents() {
jCheckBoxMenuItem1 = new javax.swing.JCheckBoxMenuItem();
jToggleButton1 = new javax.swing.JToggleButton();
jScrollPane1 = new javax.swing.JScrollPane();
chatArea = new javax.swing.JTextArea();
input = new javax.swing.JTextField();
send = new javax.swing.JButton();
user = new javax.swing.JTextField();
userset = new javax.swing.JButton();
autoscrollCheck = new javax.swing.JCheckBox();
jLabel1 = new javax.swing.JLabel();
jCheckBoxMenuItem1.setSelected(true);
jCheckBoxMenuItem1.setText("jCheckBoxMenuItem1");
jToggleButton1.setText("jToggleButton1");
setDefaultCloseOperation(javax.swing.WindowConstants.EXIT_ON_CLOSE);
setTitle("Minecraft Chat");
addWindowListener(new java.awt.event.WindowAdapter() {
public void windowOpened(java.awt.event.WindowEvent evt) {
formWindowOpened(evt);
}
public void windowClosing(java.awt.event.WindowEvent evt) {
formWindowClosing(evt);
}
});
chatArea.setEditable(false);
chatArea.setBackground(new java.awt.Color(0, 0, 0));
chatArea.setColumns(20);
chatArea.setFont(new java.awt.Font("Consolas", 0, 14)); // NOI18N
chatArea.setForeground(new java.awt.Color(255, 255, 255));
chatArea.setLineWrap(true);
chatArea.setRows(5);
jScrollPane1.setViewportView(chatArea);
input.setToolTipText("Enter message here");
input.addKeyListener(new java.awt.event.KeyAdapter() {
public void keyPressed(java.awt.event.KeyEvent evt) {
inputKeyPressed(evt);
}
});
send.setText("Send");
send.addActionListener(new java.awt.event.ActionListener() {
public void actionPerformed(java.awt.event.ActionEvent evt) {
sendActionPerformed(evt);
}
});
user.setToolTipText("");
user.addActionListener(new java.awt.event.ActionListener() {
public void actionPerformed(java.awt.event.ActionEvent evt) {
userActionPerformed(evt);
}
});
user.addKeyListener(new java.awt.event.KeyAdapter() {
public void keyPressed(java.awt.event.KeyEvent evt) {
userKeyPressed(evt);
}
});
userset.setText("Set");
userset.addActionListener(new java.awt.event.ActionListener() {
public void actionPerformed(java.awt.event.ActionEvent evt) {
usersetActionPerformed(evt);
}
});
autoscrollCheck.setSelected(true);
autoscrollCheck.setText("Auto Scroll");
autoscrollCheck.addActionListener(new java.awt.event.ActionListener() {
public void actionPerformed(java.awt.event.ActionEvent evt) {
autoscrollCheckActionPerformed(evt);
}
});
jLabel1.setText("Enter Username:");
javax.swing.GroupLayout layout = new javax.swing.GroupLayout(getContentPane());
getContentPane().setLayout(layout);
layout.setHorizontalGroup(
layout.createParallelGroup(javax.swing.GroupLayout.Alignment.LEADING)
.addGroup(layout.createSequentialGroup()
.addGap(10, 10, 10)
.addGroup(layout.createParallelGroup(javax.swing.GroupLayout.Alignment.LEADING)
.addGroup(javax.swing.GroupLayout.Alignment.TRAILING, layout.createSequentialGroup()
.addComponent(jLabel1)
.addPreferredGap(javax.swing.LayoutStyle.ComponentPlacement.RELATED)
.addComponent(user, javax.swing.GroupLayout.PREFERRED_SIZE, 218, javax.swing.GroupLayout.PREFERRED_SIZE)
.addPreferredGap(javax.swing.LayoutStyle.ComponentPlacement.RELATED)
.addComponent(userset)
.addPreferredGap(javax.swing.LayoutStyle.ComponentPlacement.RELATED, javax.swing.GroupLayout.DEFAULT_SIZE, Short.MAX_VALUE)
.addComponent(autoscrollCheck))
.addComponent(jScrollPane1)
.addGroup(javax.swing.GroupLayout.Alignment.TRAILING, layout.createSequentialGroup()
.addComponent(input, javax.swing.GroupLayout.PREFERRED_SIZE, 649, javax.swing.GroupLayout.PREFERRED_SIZE)
.addPreferredGap(javax.swing.LayoutStyle.ComponentPlacement.RELATED, javax.swing.GroupLayout.DEFAULT_SIZE, Short.MAX_VALUE)
.addComponent(send)))
.addGap(10, 10, 10))
);
layout.setVerticalGroup(
layout.createParallelGroup(javax.swing.GroupLayout.Alignment.LEADING)
.addGroup(layout.createSequentialGroup()
.addGap(11, 11, 11)
.addGroup(layout.createParallelGroup(javax.swing.GroupLayout.Alignment.LEADING)
.addGroup(layout.createSequentialGroup()
.addGap(1, 1, 1)
.addGroup(layout.createParallelGroup(javax.swing.GroupLayout.Alignment.BASELINE)
.addComponent(user, javax.swing.GroupLayout.PREFERRED_SIZE, javax.swing.GroupLayout.DEFAULT_SIZE, javax.swing.GroupLayout.PREFERRED_SIZE)
.addComponent(jLabel1)))
.addComponent(userset)
.addComponent(autoscrollCheck))
.addGap(6, 6, 6)
.addComponent(jScrollPane1, javax.swing.GroupLayout.DEFAULT_SIZE, 316, Short.MAX_VALUE)
.addGap(6, 6, 6)
.addGroup(layout.createParallelGroup(javax.swing.GroupLayout.Alignment.LEADING)
.addGroup(layout.createSequentialGroup()
.addGap(1, 1, 1)
.addComponent(input, javax.swing.GroupLayout.PREFERRED_SIZE, javax.swing.GroupLayout.DEFAULT_SIZE, javax.swing.GroupLayout.PREFERRED_SIZE))
.addComponent(send))
.addGap(11, 11, 11))
);
pack();
}// </editor-fold>
String username = null;
private void inputKeyPressed(java.awt.event.KeyEvent evt) {
int key = evt.getKeyCode();
if (key == KeyEvent.VK_ENTER) {
send(username, input.getText());
input.setText("");
}
}
private void sendActionPerformed(java.awt.event.ActionEvent evt) {
send(username, input.getText());
input.setText("");
}
private void usersetActionPerformed(java.awt.event.ActionEvent evt) {
if(username == null){
if(!"".equals(user.getText())){
username = user.getText();
chatArea.append("Username set!"+"\n\r");
if(autoscrollCheck.isSelected()){
chatArea.setCaretPosition(chatArea.getText().length() - 1);
}
}else{
chatArea.append("Username can not be blank."+"\n\r");
if(autoscrollCheck.isSelected()){
chatArea.setCaretPosition(chatArea.getText().length() - 1);
}
}
}else{
send(username, "§7changed name to " + user.getText());
username = user.getText();
}
}
private void userActionPerformed(java.awt.event.ActionEvent evt) {
// TODO add your handling code here:
}
private void userKeyPressed(java.awt.event.KeyEvent evt) {
int key = evt.getKeyCode();
if (key == KeyEvent.VK_ENTER) {
if(username == null){
if(!"".equals(user.getText())){
username = user.getText();
chatArea.append("Username set!"+"\n\r");
if(autoscrollCheck.isSelected()){
chatArea.setCaretPosition(chatArea.getText().length() - 1);
}
}else{
chatArea.append("Username can not be blank."+"\n\r");
if(autoscrollCheck.isSelected()){
chatArea.setCaretPosition(chatArea.getText().length() - 1);
}
}
}else{
send(username, "§7changed name to " + user.getText());
username = user.getText();
}
}
}
private void formWindowClosing(java.awt.event.WindowEvent evt) {
}
private void formWindowOpened(java.awt.event.WindowEvent evt) {
// TODO add your handling code here:
}
private void autoscrollCheckActionPerformed(java.awt.event.ActionEvent evt) {
// TODO add your handling code here:
}
/**
* #param args the command line arguments
*/
public static void main(String args[]) throws IOException {
/* Set the system look and feel */
//<editor-fold defaultstate="collapsed" desc=" Look and feel setting code ">
/* If Nimbus (introduced in Java SE 6) is not available, stay with the default look and feel.
* For details see http://download.oracle.com/javase/tutorial/uiswing/lookandfeel/plaf.html
*/
try {
javax.swing.UIManager.setLookAndFeel(UIManager.getSystemLookAndFeelClassName());
} catch (ClassNotFoundException ex) {
java.util.logging.Logger.getLogger(chat.class.getName()).log(java.util.logging.Level.SEVERE, null, ex);
} catch (InstantiationException ex) {
java.util.logging.Logger.getLogger(chat.class.getName()).log(java.util.logging.Level.SEVERE, null, ex);
} catch (IllegalAccessException ex) {
java.util.logging.Logger.getLogger(chat.class.getName()).log(java.util.logging.Level.SEVERE, null, ex);
} catch (javax.swing.UnsupportedLookAndFeelException ex) {
java.util.logging.Logger.getLogger(chat.class.getName()).log(java.util.logging.Level.SEVERE, null, ex);
}
//</editor-fold>
/* Create and display the form */
java.awt.EventQueue.invokeLater(new Runnable() {
#Override
public void run() {
new chat().setVisible(true);
}
});
Socket socket = null;
PrintWriter out = null;
BufferedReader in = null;
try {
socket = new Socket("mc.xxx.net", 20060);
out = new PrintWriter(socket.getOutputStream(), true);
in = new BufferedReader(new InputStreamReader(socket.getInputStream()));
} catch (UnknownHostException e) {
System.err.println("Don't know about host");
System.exit(1);
} catch (IOException e) {
System.err.println("Couldn't get I/O for the connection");
System.exit(1);
}
BufferedReader read = new BufferedReader(new InputStreamReader(System.in));
//System.out.println(in.readLine()); //Uncomment to debug
out.println("/api/subscribe?source=chat&key=1e287587f5d1d45255f4708467eeaf8a71085f9ccfd8a354523d233cf5a77be4&show_previous=true");
out.println("/api/subscribe?source=connections&key=e410592b70c0288654e6c1040edb0f21811dcb3f2ee11051163f36be9be00788&show_previous=false");
while(true){
String jsonString = in.readLine();
JSONObject obj = JSONObject.fromObject(jsonString);
JSONObject success = obj.getJSONObject("success");
if(success.get("message") != null){
chatArea.append("<" + success.get("player") + "> " + success.get("message") + "\n\r");
if(autoscrollCheck.isSelected()){
chatArea.setCaretPosition(chatArea.getText().length() - 1);
}
}else if (success.get("action") != null){
chatArea.append(success.get("player") + " " + success.get("action") + "\n\r");
if(autoscrollCheck.isSelected()){
chatArea.setCaretPosition(chatArea.getText().length() - 1);
}
}
}
}
// Variables declaration - do not modify
public static javax.swing.JCheckBox autoscrollCheck;
public static javax.swing.JTextArea chatArea;
private javax.swing.JTextField input;
private javax.swing.JCheckBoxMenuItem jCheckBoxMenuItem1;
private javax.swing.JLabel jLabel1;
private javax.swing.JScrollPane jScrollPane1;
private javax.swing.JToggleButton jToggleButton1;
private javax.swing.JButton send;
private javax.swing.JTextField user;
private javax.swing.JButton userset;
// End of variables declaration
}
(P.S Please don't get grumpy because I'm using a GUI generator, this is my first program, I promise I will learn to do it by hand )

The only thing that can be null at line 333 is chatArea. (If success were null, it would've thrown an exception in the if statement at line 332.) As others have suggested, you probably have a race condition where it's not being initialized before line 333 is reached.
The correct way to fix it is to enclose chatArea calls in a call to SwingUtilities.invokeLater:
final JSONObject success = obj.getJSONObject("success");
SwingUtilities.invokeLater(new Runnable() {
public void run() {
if (success.get("message") != null) {
chatArea.append("<" + success.get("player") + "> " + success.get("message") + "\n\r");
if (autoscrollCheck.isSelected()) {
chatArea.setCaretPosition(chatArea.getText().length() - 1);
}
} else if (success.get("action") != null) {
chatArea.append(success.get("player") + " " + success.get("action") + "\n\r");
if (autoscrollCheck.isSelected()) {
chatArea.setCaretPosition(chatArea.getText().length() - 1);
}
}
}
});
Any time you make a change to a Swing component, you should call it in the event dispatch thread. What's more, since the EDT is single-threaded, queue-based kind of executor, this is guaranteed to wait until the runnable you submitted earlier is done, so chatArea will definitely be set.
One other note: it's generally good practice to wrap UIManager calls in an invokeLater call as well.
Edit: I just want to be a little more clear about what you should always wrap in an invokeLater call:
Constructing Swing components
Changing properties of Swing components
Modifying the data model of a Swing component (not necessarily getting the data, just telling the component that cares that it has changed, such as firing events, needs to happen on the EDT)
Modifying UIManager properties, including setting the look and feel or modifying the values of its keys
Instantiating a look and feel
Instantiating sublcasses of ComponentUI
Adding and removing components to and from a container
Things that don't need to be wrapped:
Changing properties on components that aren't displayed yet According to Robin in the comments, this still needs to happen on the EDT.
Calls to repaint
Calls to validate, or invalidate (I think, I need to find confirmation on this)
Do all this, and any time you switch to a new look and feel, you won't have any problems with things not being called on the EDT.
Long story short, Swing isn't thread-safe, so you should always call Swing component methods from the event dispatch thread.
Also, I welcome any suggestions for my list about things I may have forgotten.
Here's are some resources that describe threading in Swing:
Java SE 6 javax.swing javadocs
Java trail on Swing concurrency
Old blog post about the decision to make Swing single-threaded (in case you're curious)

The problem is that you're readily switching between static and non-static data. Initially, the program runs main() (static). Therein, you reference chatArea (line 333, also static). However, chatArea is only set upon calling initComponents() (non-static), which happens in the constructor (non-static). This will not always be called before the remainder of the function.
Based on your invokeLater methodology, you should move everything related to the chat program, which comes after invokeLater, into the constructor (or some method which is not static).
Basically, the only thing that should be static is your main() method. The rest should not be static. If it helps, separate things into a new class, which you reference from main(); this will help you initialize the program, then run all your chat-related things.

It is probably a race condition which makes it work sometimes. The variable chatArea is not guaranteed to be initialized by the time the main thread gets to line 333. This is due to the deferred initialization of the GUI via invokeLater() some lines before that:
java.awt.EventQueue.invokeLater(new Runnable() {
#Override
public void run() {
new chat().setVisible(true);
}
});
You need some synchronization between those threads, or, what also should work, just initialize the GUI in the main thread:
final chat chatObject = new chat();
java.awt.EventQueue.invokeLater(new Runnable() {
#Override
public void run() {
chatObject.setVisible(true);
}
});

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