Develop Reference

How can I get the contents of my GUI to look a certain way? (Java)

So, I'm brand spankin' new to programming, so thanks in advance for your help. I'm trying to put this base 2 to base 10/base 10 to base 2 calculator I have made into a GUI. For the life of me I can't figure out how to nicely format it. I'm trying to make it look like the following: The two radio buttons on top, the input textfield bellow those, the convert button bellow that, the output field bellow that, and the clear button bellow that. Any ideas on how I can accomplish this?
import java.awt.Container;
import java.awt.Dimension;
import java.awt.FlowLayout;
import java.awt.event.ActionEvent;
import java.awt.event.ActionListener;
import java.awt.event.ItemEvent;
import java.awt.event.ItemListener;
import java.awt.GridLayout;
import java.awt.BorderLayout;
import java.awt.Color;
import javax.swing.*;
#SuppressWarnings("serial")
public class GUI extends JFrame implements ActionListener
{
private JTextField input;
private JTextField output;
private JRadioButton base2Button;
private JRadioButton base10Button;
private JButton convert;
private JButton clear;
private Container canvas = getContentPane();
private Color GRAY;
public GUI()
{
this.setTitle("Base 10-2 calc");
this.setLayout(new FlowLayout(FlowLayout.LEFT));
//this.setLayout(new GridLayout(2,2));
base2Button = new JRadioButton( "Convert to base 2");
base10Button = new JRadioButton( "Convert to base 10");
ButtonGroup radioGroup = new ButtonGroup();
radioGroup.add(base2Button);
radioGroup.add(base10Button);
JPanel radioButtonsPanel = new JPanel();
radioButtonsPanel.setLayout( new FlowLayout(FlowLayout.LEFT) );
radioButtonsPanel.add(base2Button);
radioButtonsPanel.add(base10Button);
canvas.add(radioButtonsPanel);
base2Button.setSelected( true );
base10Button.setSelected( true );
input = new JTextField(18);
//input = new JFormattedTextField(20);
canvas.add(input);
output = new JTextField(18);
//output = new JFormattedTextField(20);
canvas.add(output);
convert = new JButton("Convert!");
convert.addActionListener(this);
canvas.add(convert);
clear = new JButton("Clear");
clear.addActionListener(this);
canvas.add(clear);
output.setBackground(GRAY);
output.setEditable(false);
this.setSize(300, 200);
this.setVisible(true);
this.setLocation(99, 101);
this.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
}
public static void main(String[] args)
{
GUI app = new GUI();
app.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
}
#Override
public void actionPerformed(ActionEvent e)
{
String s = e.getActionCommand();
if(s.equals("Convert!"))
{
String numS = input.getText();
int numI = Integer.parseInt(numS);
if(base2Button.isSelected())
{
output.setText(Integer.toBinaryString(Integer.valueOf(numI)));
}
if(base10Button.isSelected())
{
output.setText("" + Integer.valueOf(numS,2));
}
}
if(s.equals("Clear"))
{
input.setText("");
output.setText("");
}
}
}

For a simple layout, you could use a GridLayout with one column and then use a bunch of child panels with FlowLayout which align the components based on the available space in a single row. If you want more control, I'd suggest learning about the GridBagLayout manager which is a more flexible version of GridLayout.
public class ExampleGUI {
public ExampleGUI() {
init();
}
private void init() {
JFrame frame = new JFrame();
// Set the frame's layout to a GridLayout with one column
frame.setLayout(new GridLayout(0, 1));
frame.setPreferredSize(new Dimension(300, 300));
frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
// Child panels, each with FlowLayout(), which aligns the components
// in a single row, until there's no more space
JPanel radioButtonPanel = new JPanel(new FlowLayout());
JRadioButton button1 = new JRadioButton("Option 1");
JRadioButton button2 = new JRadioButton("Option 2");
radioButtonPanel.add(button1);
radioButtonPanel.add(button2);
JPanel inputPanel = new JPanel(new FlowLayout());
JLabel inputLabel = new JLabel("Input: ");
JTextField textField1 = new JTextField(15);
inputPanel.add(inputLabel);
inputPanel.add(textField1);
JPanel convertPanel = new JPanel(new FlowLayout());
JButton convertButton = new JButton("Convert");
convertPanel.add(convertButton);
JPanel outputPanel = new JPanel(new FlowLayout());
JLabel outputLabel = new JLabel("Output: ");
JTextField textField2 = new JTextField(15);
outputPanel.add(outputLabel);
outputPanel.add(textField2);
// Add the child panels to the frame, in order, which all get placed
// in a single column
frame.add(radioButtonPanel);
frame.add(inputPanel);
frame.add(convertPanel);
frame.add(outputPanel);
frame.pack();
frame.setVisible(true);
}
public static void main(String[] args) {
ExampleGUI example = new ExampleGUI();
}
}
The end result:

Adding an action listener to JButtons created by a loop

I am having trouble finding a way to invoke an action listener that returns the value of the button clicked in the text area at the bottom.
I made the buttons using a for loop and did not expressly give the buttons a name so I do not know how to reference them when trying to incorporate an ActionListener.
import javax.swing.*;
import java.awt.*;
import java.awt.event.ActionEvent;
import java.awt.event.ActionListener;
public class buttoner implements ActionListener {
//JFrame
JFrame frame = new JFrame("Button Game");
//Make JPanels
JPanel panelLabel = new JPanel();
JPanel buttonGrid = new JPanel(new GridLayout(0,10));
JPanel bottomPanel = new JPanel();
//JLabel
private JLabel label1 = new JLabel("The Button Game");
public buttoner() {
//set layout
frame.setLayout(new BorderLayout());
frame.add(panelLabel, BorderLayout.NORTH);
frame.add(buttonGrid, BorderLayout.CENTER);
frame.add(bottomPanel, BorderLayout.SOUTH);
//Set stuff
frame.setLocationRelativeTo(null);
frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
frame.setSize(500,700);
frame.setVisible(true);
//Change label color
label1.setForeground(Color.RED);
//add Label
panelLabel.add(label1);
//add Buttons
for (int i = 1; i <= 60; i++) {
String val = Integer.toString(i);
buttonGrid.add(new JButton(val));
}
//Add JText Area to bottom JPanel
String num = "value";
JTextArea jta = new JTextArea(num, 1, 1);
bottomPanel.add(jta);
frame.pack();
}
public static void main(String args[]){
buttoner gui = new buttoner();
}
public void actionPerformed(ActionEvent a) {
}
}

I created an action listener to put the value in the text area at the bottom of the GUI.
I fixed a few problems with your code.
In the main method, I called the SwingUtilities invokeLater method to put the Swing GUI on the Event Dispatch thread (EDT). Swing components must be created and updated on the EDT.
The name of a Java class must start with a capital letter.
It's safer to put your Swing components on a JPanel, rather than add them directly to a JFrame.
I separated the code that creates the JFrame from the code that creates the JPanels. It should be easier for any reader of your code, including yourself, to understand what's going on.
In the createMainPanel method, I grouped the code so that everything having to do with the buttonGrid JPanel, to take one instance, is in one place in the code.
I added the action listener to the code that creates the buttonGrid JPanel.
I wrote action listener code that updates the JTextArea with the left clicked button label.
Here's the corrected code.
package com.ggl.testing;
import java.awt.BorderLayout;
import java.awt.Color;
import java.awt.GridLayout;
import java.awt.event.ActionEvent;
import java.awt.event.ActionListener;
import javax.swing.JButton;
import javax.swing.JFrame;
import javax.swing.JLabel;
import javax.swing.JPanel;
import javax.swing.JTextArea;
import javax.swing.SwingUtilities;
public class Buttoner implements ActionListener {
// JFrame
private JFrame frame = new JFrame("Button Game");
// Make JPanels
private JPanel panelLabel = new JPanel();
private JPanel buttonGrid = new JPanel(new GridLayout(0, 10));
private JPanel bottomPanel = new JPanel();
// JLabel
private JLabel label1 = new JLabel("The Button Game");
private JTextArea jta;
public Buttoner() {
frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
frame.add(createMainPanel());
frame.pack();
frame.setLocationByPlatform(true);
frame.setVisible(true);
}
private JPanel createMainPanel() {
JPanel panel = new JPanel();
panel.setLayout(new BorderLayout());
// Change label color
label1.setForeground(Color.RED);
// add Label
panelLabel.add(label1);
panel.add(panelLabel, BorderLayout.NORTH);
// add Buttons
for (int i = 1; i <= 60; i++) {
String val = Integer.toString(i);
JButton button = new JButton(val);
button.addActionListener(this);
buttonGrid.add(button);
}
panel.add(buttonGrid, BorderLayout.CENTER);
// Add JText Area to bottom JPanel
String num = "value";
jta = new JTextArea(num, 1, 1);
jta.setEditable(false);
bottomPanel.add(jta);
panel.add(bottomPanel, BorderLayout.SOUTH);
return panel;
}
public static void main(String args[]) {
Runnable runnable = new Runnable() {
#Override
public void run() {
new Buttoner();
}
};
SwingUtilities.invokeLater(runnable);
}
public void actionPerformed(ActionEvent a) {
JButton button = (JButton) a.getSource();
jta.setText(button.getText());
}
}

Try creating an array of buttons and add the newly created button to the array. See comments.
import javax.swing.*;
import java.awt.*;
import java.awt.event.ActionEvent;
import java.awt.event.ActionListener;
public class buttoner implements ActionListener {
//JFrame
JFrame frame = new JFrame("Button Game");
//Make JPanels
JPanel panelLabel = new JPanel();
JPanel buttonGrid = new JPanel(new GridLayout(0,10));
JPanel bottomPanel = new JPanel();
//JLabel
private JLabel label1 = new JLabel("The Button Game");
private JButton buttons[] = new JButton[60]; //create an array of button for future reference
public buttoner() {
//set layout
frame.setLayout(new BorderLayout());
frame.add(panelLabel, BorderLayout.NORTH);
frame.add(buttonGrid, BorderLayout.CENTER);
frame.add(bottomPanel, BorderLayout.SOUTH);
//Set stuff
frame.setLocationRelativeTo(null);
frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
frame.setSize(500,700);
frame.setVisible(true);
//Change label color
label1.setForeground(Color.RED);
//add Label
panelLabel.add(label1);
//add Buttons
for (int i = 1; i <= 60; i++) {
String val = Integer.toString(i);
JButton btn = new JButton(val);
btn.addActionListener(this); //add an actionListener right away
buttons[i] = btn; //add the button in the array for future reference
buttonGrid.add(btn);
}
//Add JText Area to bottom JPanel
String num = "value";
JTextArea jta = new JTextArea(num, 1, 1);
bottomPanel.add(jta);
frame.pack();
}
public static void main(String args[]){
buttoner gui = new buttoner();
}
public void actionPerformed(ActionEvent a) {
}
}

Java syntax for separating action listeners

Please help me out to separate these ActionListeners in a periodic table that I am attempting to complete. When I execute the program and click on 'H', it opens all the other elements and when the others are clicked, it does not work. So I need a way to separate these using any method...
import javax.swing.*;
import java.awt.*;
import java.awt.event.*;
public class PeriodicTable
{
public static void main (String[] args)
{
JFrame frame = new JFrame("Elements");
frame.setVisible(true);
frame.setSize(1000,1500);
frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
JPanel panel = new JPanel();
frame.add(panel);
JButton button1 = new JButton("H");
panel.add(button1);
button1.addActionListener (new Action1());
JButton button2 = new JButton("He");
panel.add(button2);
button2.addActionListener (new Action2());
JButton button3 = new JButton("Li");
panel.add(button3);
button3.addActionListener (new Action2());
}
static class Action1 implements ActionListener
{
public void actionPerformed (ActionEvent e)
{
JFrame frame2 = new JFrame("H");
frame2.setVisible(true);
frame2.setSize(1000,1500);
JLabel label = new JLabel("Hydrogen");
JPanel panel = new JPanel();
frame2.add(panel);
panel.add(label);
}
}
static class Action2 implements ActionListener
{
public void actionPerformed (ActionEvent e)
{
JFrame frame3 = new JFrame("He");
frame3.setVisible(true);
frame3.setSize(1000,1500);
JLabel label = new JLabel("Helium");
JPanel panel = new JPanel();
frame3.add(panel);
panel.add(label);
}
}
static class Action3 implements ActionListener
{
public void actionPerformed (ActionEvent e)
{
JFrame frame4 = new JFrame("Li");
frame4.setVisible(true);
frame4.setSize(1000,1500);
JLabel label = new JLabel("Lithium");
JPanel panel = new JPanel();
frame4.add(panel);
panel.add(label);
}
}
}
Thanks in advance.
(note: only the first 3 elements are coded for...)

When I execute the program and click on 'H', it opens all other elements
Only one frame opens for me.
and when the others are clicked, it does not work.
Each button opens a single frame for me.
However, button 3 opens the wrong frame because you add the wrong listener to the button:
//button3.addActionListener (new Action2());
button3.addActionListener (new Action3());
Other issues:
You should add the components to the frame BEFORE making the frame visible.
Don't hardcode screen sizes, you never know what size screen other users will be using
So the order of your code might be something like:
JLabel label = new JLabel("Helium");
JPanel panel = new JPanel();
panel.add(label);
JFrame frame3 = new JFrame("He");
frame3.add(panel);
frame3.pack();
frame3.setVisible(true);
And of course you really don't want to create dozens of separate ActionListeners. You want to make the listener more generic so it can be shared.
Something like:
static class Action implements ActionListener
{
public Action(String element, String description)
{
this.element = element;
this.description = description;
}
public void actionPerformed (ActionEvent e)
{
JLabel label = new JLabel(description);
JPanel panel = new JPanel();
panel.add(label);
JFrame frame3 = new JFrame(element);
frame3.add(panel);
frame3.pack();
frame3.setVisible(true);
}
}
Then when you create the listener you use:
button3.addActionListener (new Action("HE", "Helium"));

Java GUI - Possible to store JPanels inside a single main JPanel?

I am working on a semester project that I have and I was wondering if it was possible to store 3-4 JPanels instead one single "main" JPanel. The reason for me asking this is because I a trying to make a GUI checkbook program and my checkbook has 7 buttons that should open a new window once I click on it. To switch between each window I'm going to have to use the CardLayout, but my understand of the CardLayout is that I can only assign one single JPanel to that card so I can't assign multiple JPanels to a single Card layout so when the user clicks on a different card 3-4 different JPanels appear.
The reason that I am asking this is because I asked for help earlier and received help for creating my first window in this project, it produces the output I want PERFECTLY, but uses more than 1 JPanel in doing so. Since this prevents me from continuing on to the other steps of my 7 GUI Windows, I am stuck.
Here is the code:
import java.awt.*;
import javax.swing.*;
import java.awt.event.ActionEvent;
import java.awt.event.ActionListener;
public class checkbook extends JPanel implements ActionListener {
private static final String title = "Use The Buttons Below To Manage Transactions";
private static final String[] bottomButtons = { "Create a New Account",
"Load a Trans from a File", "Add New Transactions",
"Search Transactions", "Sort Transactions",
"View/Delete Transactions", "Backup Transaction", "Exit" };
static JButton Button[] = new JButton[8];
static ActionListener AL = new checkbook();
public checkbook() {
JLabel titleLabel = new JLabel(title, SwingConstants.CENTER);
titleLabel.setFont(titleLabel.getFont().deriveFont(Font.BOLD, 18));
JPanel titlePanel = new JPanel();
titlePanel.add(titleLabel); // put it in a JPanel so it will expand to fill BoxLayout
JTextField textfield = new JTextField();
JPanel accountBalancePanel = new JPanel();
accountBalancePanel.add(new JLabel("Account Name:"));
accountBalancePanel.add(new JTextField(10));
accountBalancePanel.add(Box.createHorizontalStrut(4));
accountBalancePanel.add(new JLabel("Balance:"));
textfield = new JTextField("0.0", 10);
textfield.setHorizontalAlignment(JTextField.RIGHT);
accountBalancePanel.add(textfield);
JPanel northPanel = new JPanel();
northPanel.setLayout(new BoxLayout(northPanel, BoxLayout.PAGE_AXIS));
northPanel.add(titlePanel);
northPanel.add(accountBalancePanel);
JPanel southBtnPanel = new JPanel(new GridLayout(2, 4, 1, 1));
for(int i = 0; i < 8; i++){
Button[i] = new JButton(bottomButtons[i]);
southBtnPanel.add(Button[i]);
Button[i].addActionListener(AL);
}
setBorder(BorderFactory.createEmptyBorder(1, 1, 1, 1));
setLayout(new BorderLayout());
add(northPanel, BorderLayout.NORTH);
add(Box.createRigidArea(new Dimension(100, 100))); // just an empty placeholder
add(southBtnPanel, BorderLayout.SOUTH);
}
private static void createAndShowGui() {
checkbook mainPanel = new checkbook();
JFrame frame = new JFrame("Checkbook");
frame.setDefaultCloseOperation(JFrame.DISPOSE_ON_CLOSE);
frame.getContentPane().add(mainPanel);
frame.pack();
frame.setLocationByPlatform(true);
frame.setVisible(true);
}
public static void main(String[] args) {
SwingUtilities.invokeLater(
new Runnable() {
public void run() {
createAndShowGui();
}
});
}
public void actionPerformed(ActionEvent e)
{
if(e.getSource() == Button[7]) {
System.exit(0);
}
}
}
Credit goes to Hovercraft Full Of Eels for showing me the above example
If there is anything that is unclear about my question, please ask and I will do the best I can to fix it.
Here is what the code produces:
http://i.stack.imgur.com/WY0c3.png

Java - Tic Tac Toe Swing game - Errors

I am making a tic tac toe game in Java and made the gui and wanted to run it to test it but am getting a few errors. I am not sure why and was hoping that someone could explain why those errors are coming up and what i should do to fix them. The errors that I am getting are as follows: Exception in thread "main" java.lang.NullPointerException
at TicTacToeSwing.(TicTacToeSwing.java:84)
at TicTacToeSwing.main(TicTacToeSwing.java:180)
Here is my code: (please note: I have not done the calculations yet because I wanted to get the gui going first) If you know of a better practice that I should consider doing, by all means, let me know.
import java.awt.BorderLayout;
import java.awt.Color;
import java.awt.Container;
import java.awt.GridLayout;
import java.awt.event.ActionListener;
import javax.swing.JButton;
import javax.swing.JFrame;
import javax.swing.JLabel;
import javax.swing.JPanel;
import javax.swing.JTextField;
import java.awt.*;
import java.awt.event.*;
import javax.swing.*;
//Tic Tac Toe
public class TicTacToeSwing extends JFrame
implements ActionListener {
//JButtons
//private JButton button1 = new JButton("");
private JButton jbtnTicTacToe1;
private JButton jbtnTicTacToe2;
private JButton jbtnTicTacToe3;
private JButton jbtnTicTacToe4;
private JButton jbtnTicTacToe5;
private JButton jbtnTicTacToe6;
private JButton jbtnTicTacToe7;
private JButton jbtnTicTacToe8;
private JButton jbtnTicTacToe9;
private JButton jbtnExit;
private JButton jbtnReset;
//JFrame window = new JFrame("Tic-Tac-Toe Swing ");
private JFrame window = new JFrame("Tic-Tac-Toe");
//labels
private JLabel jlblPlayerX = new JLabel ("X");
private JLabel jlblPlayerO = new JLabel ("O");
//text fields
JTextField jtfName = new JTextField(20);
private JTextField jtfPlayerX = new JTextField("X");
private JTextField jtfPlayerO = new JTextField("O");
//Panels
JPanel jpnlMain = new JPanel ();
JPanel jpnlFamily = new JPanel();
JPanel jpnlNorth = new JPanel();
JPanel jpnlSouth = new JPanel();
JPanel jpnlCenter = new JPanel();
JPanel jpnlTop = new JPanel();
JPanel jpnlBottom = new JPanel();
//Class Constructor
public TicTacToeSwing () {
//Prepare JFrame/Window
super ("Tic Tac Toe");
setSize(400,400);
setTitle("Tic Tac Toe Swing");
setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
//Set the layouts for 3 rows and 3 columns
jpnlMain.setLayout(new BorderLayout(3,3));
jpnlCenter.setLayout(new GridLayout());
jpnlSouth.setLayout(new GridLayout());
jpnlTop.setLayout(new BorderLayout());
jpnlBottom.setLayout(new BorderLayout());
//Center Panel
jpnlCenter.add(jlblPlayerX);
jpnlCenter.add(jlblPlayerO);
//identify each JButton
jbtnReset.setActionCommand("Reset");
jbtnExit.setActionCommand("Exit");
//register JButton for event handling by using the THIS keyword - THIS class will handle the events
jbtnReset.addActionListener(this);
jbtnExit.addActionListener(this);
/*Add Buttons To The Window*/
window.add(jbtnTicTacToe1);
window.add(jbtnTicTacToe2);
window.add(jbtnTicTacToe3);
window.add(jbtnTicTacToe4);
window.add(jbtnTicTacToe5);
window.add(jbtnTicTacToe6);
window.add(jbtnTicTacToe7);
window.add(jbtnTicTacToe8);
window.add(jbtnTicTacToe9);
/*Add The Action Listener To The Buttons
button1.addActionListener(this);
button2.addActionListener(this);
button3.addActionListener(this);
button4.addActionListener(this);
button5.addActionListener(this);
button6.addActionListener(this);
button7.addActionListener(this);
button8.addActionListener(this);
button9.addActionListener(this);
*/
jbtnTicTacToe1.addActionListener(this);
jbtnTicTacToe2.addActionListener(this);
jbtnTicTacToe3.addActionListener(this);
jbtnTicTacToe4.addActionListener(this);
jbtnTicTacToe5.addActionListener(this);
jbtnTicTacToe6.addActionListener(this);
jbtnTicTacToe7.addActionListener(this);
jbtnTicTacToe8.addActionListener(this);
jbtnTicTacToe9.addActionListener(this);
//South Button Panel
jpnlSouth.add(jbtnReset);
jpnlSouth.add(jbtnExit);
/* Instantiate JButtons, put into a method for efficiency
jbtn1 = instantiateJButton("1", Color.PINK);
jbtn2 = instantiateJButton("2", Color.PINK);
jbtn3 = instantiateJButton("3", Color.PINK);
jbtn4 = instantiateJButton("4", Color.PINK);
jbtn5 = instantiateJButton("5", Color.PINK);
jbtn6 = instantiateJButton("6", Color.PINK);
jbtn7 = instantiateJButton("7", Color.PINK);
jbtn8 = instantiateJButton("8", Color.PINK);
jbtn9 = instantiateJButton("9", Color.PINK);
*/
//Finalize screen layout and publish to the display
jpnlMain.add(jpnlCenter, BorderLayout.NORTH);
jpnlMain.add(jpnlSouth, BorderLayout.CENTER);
//Prepare the container
Container ca = getContentPane();
ca.setBackground (Color.LIGHT_GRAY);
ca.add(jpnlMain);
setContentPane (ca);
setVisible(true);
//end constructor
}
//CLASS EVENT HANDLER
public void actionPerformed(java.awt.event.ActionEvent e)
{
//find out which JButton was pressed by using the Action Command
String sActionCommand = e.getActionCommand();
//EXIT JButton
if (sActionCommand == "Exit")
{
System.exit(0);
}
//RESET JButton
else if (sActionCommand == "Reset")
{
jtfPlayerX.setText("");
jtfPlayerO.setText("");
}
} //end ACTIONPERFORMED (java.awt.event.ActionEvent e)
/**
* #param args
*/
public static void main(String[] args) {
//EXECUTION STARTING POINT
TicTacToeSwing TicTacToeSwing = new TicTacToeSwing();
//TicTacToeSwing TicTacToeObject = new TicTacToeSwing();
}//end main(String[] args)
}//end TicTacToeSwing class

The stacktrace has useful information about what is causing the NPE (jbtnReset which appears on line 84). Therefore you need to initialize jbtnReset:
JButton jbtnReset = new JButton("Reset");
In fact the same applys to all the jbtnTicTacToeX buttons as well as jbtnExit.
Side issues:
Use String#equals to compare String content. The == operator compares String content.
if (sActionCommand == "Exit") {
should be
if (sActionCommand.equals("Exit")) {
This checks the action command for any component with this String so you want to check the specific source object instead:
if (e.getSource() == jbtnExit) {

If you look at the stack trace, places like TicTacToeSwing.java:84 show you where the errors are occuring. TicTacToeSwing.java is the file, and :84 means line number 84.

Where you have:
private JButton jbtnExit;
private JButton jbtnReset;
Try:
private JButton jbtnExit = new JButton("Exit");
private JButton jbtnReset = new JButton("Reset");