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Java GUI Freezes Tic-Tac-Toe

I have written Tic-Tac-Toe in Java. The issue I seem to be having is when there is a tie between the (human)player 1 and the (computer) player 2, the GUI freezes. I have created a tieCheck in both the "Buttonlistener" Class and the "Methods" to catch a tie.
The way my program works is that when a button is pressed, it passes a value to the array in the methods class. in this array, 1 = player 1, and 2 = player 2.
The human player always goes first, so when the human player has gone 4 times, I check for a tie before the last turn is taken with tieCheck(turncount); this method then utilizes the tieCheck() in the methods class which will place a 1 in the last place and then checks for a winner. if no winner is found, it returns true. then the tieCheck() from the ButtonListener class will disable all the buttons, and say "it is a tie". However, none of this is working. The program will still allow me to make the last move and will result in a frozen window I have to close using task manager. please help!
import javax.swing.*;
import java.awt.*;
import java.awt.event.ActionEvent;
import java.awt.event.ActionListener;
public class MediumPanel extends JPanel {
private static final long serialVersionUID = 1L;
private JButton playAgain;
private JButton[] buttons = new JButton[9];
private JLabel label, turn;
public MediumPanel() {
ButtonListener listener = new ButtonListener();
Font f1 = new Font("Arial", Font.BOLD , 100);
Font f2 = new Font("Arial", Font.PLAIN, 50);
JPanel ButtonPanel = new JPanel();
ButtonPanel.setLayout(new GridLayout(3, 3));
for (int i = 0; i <= 8; i++) {
buttons[i] = new JButton("");
buttons[i].addActionListener(listener);
buttons[i].setBackground(Color.white);
buttons[i].setFont(f1);
ButtonPanel.add(buttons[i]);
}
playAgain = new JButton();
label = new JLabel();
label.setFont(f2);
turn = new JLabel("");
turn.setFont(f1);
playAgain.addActionListener(listener);
playAgain.setText("Click to Play Again");
playAgain.setFont(f2);
setBackground(Color.green);
setLayout(new BorderLayout());
setPreferredSize(new Dimension(500, 500));
add(playAgain, BorderLayout.SOUTH);
add(label, BorderLayout.NORTH);
add(ButtonPanel);
}
private class ButtonListener implements ActionListener {
Methods method = new Methods();
public void reset() {
label.setText("");
for (int i = 0; i <= 8; i++) {
buttons[i].setEnabled(true);
buttons[i].setText("");
}
method.reset();
}
// inserts
public void insertG(int num) {
for (int i = 0; i <= 8; i++) {
if (num == i) {
buttons[i].setText("O");
buttons[i].setEnabled(false);
}
}
}
public void disable() {
for(int i=0; i<=8; i++) {
buttons[i].setEnabled(false);
}
}
// Checks array using tieCheck from Methods class for a tie
public void tieCheck(int turncount) {
if (turncount == 4 && method.tieCheck() == true) {
disable();
label.setText("It's a tie!");
}
}
// Checks for buttons being pressed
public void actionPerformed(ActionEvent event) {
int turncount = 0;
//Resets array board, GUI buttons, and label when clicked
if (event.getSource() == playAgain) {
reset();
}
// Button 0
if (event.getSource() == buttons[0]) {
buttons[0].setText("X");
buttons[0].setEnabled(false);
turncount++;
tieCheck(turncount);
method.insertArray(0, 1);
if (method.winCheck(1) == 1) {
label.setText("You Won!");
disable();
} else {
insertG(method.smartMove(1, 2));
if (method.winCheck(2) == 1) {
label.setText("You Lost!");
disable();
}
}
}
// Button 1
if (event.getSource() == buttons[1]) {
buttons[1].setText("X");
buttons[1].setEnabled(false);
turncount++;
tieCheck(turncount);
method.insertArray(1, 1);
if (method.winCheck(1) == 1) {
label.setText("You Won!");
disable();
} else {
insertG(method.smartMove(1, 2));
if (method.winCheck(2) == 1) {
label.setText("You Lost!");
disable();
}
}
}
// Button 2
if (event.getSource() == buttons[2]) {
buttons[2].setText("X");
buttons[2].setEnabled(false);
turncount++;
tieCheck(turncount);
method.insertArray(2, 1);
if (method.winCheck(1) == 1) {
label.setText("You Won!");
disable();
} else {
insertG(method.smartMove(1, 2));
if (method.winCheck(2) == 1) {
label.setText("You Lost!");
disable();
}
}
}
// Button 3
if (event.getSource() == buttons[3]) {
buttons[3].setText("X");
buttons[3].setEnabled(false);
turncount++;
tieCheck(turncount);
method.insertArray(3, 1);
if (method.winCheck(1) == 1) {
label.setText("You Won!");
disable();
} else {
insertG(method.smartMove(1, 2));
if (method.winCheck(2) == 1) {
label.setText("You Lost!");
disable();
}
}
}
// Button 4
if (event.getSource() == buttons[4]) {
buttons[4].setText("X");
buttons[4].setEnabled(false);
turncount++;
tieCheck(turncount);
method.insertArray(4, 1);
if (method.winCheck(1) == 1) {
label.setText("You Won!");
disable();
} else {
insertG(method.smartMove(1, 2));
if (method.winCheck(2) == 1) {
label.setText("You Lost!");
disable();
}
}
}
// Button 5
if (event.getSource() == buttons[5]) {
buttons[5].setText("X");
buttons[5].setEnabled(false);
turncount++;
tieCheck(turncount);
method.insertArray(5, 1);
if (method.winCheck(1) == 1) {
label.setText("You Won!");
disable();
} else {
insertG(method.smartMove(1, 2));
if (method.winCheck(2) == 1) {
label.setText("You Lost!");
disable();
}
}
}
//Button 6
if (event.getSource() == buttons[6]) {
buttons[6].setText("X");
buttons[6].setEnabled(false);
turncount++;
tieCheck(turncount);
method.insertArray(6, 1);
if (method.winCheck(1) == 1) {
label.setText("You Won!");
disable();
} else {
insertG(method.smartMove(1, 2));
if (method.winCheck(2) == 1) {
label.setText("You Lost!");
disable();
}
}
}
// Button 7
if (event.getSource() == buttons[7]) {
buttons[7].setText("X");
buttons[7].setEnabled(false);
turncount++;
tieCheck(turncount);
method.insertArray(7, 1);
if (method.winCheck(1) == 1) {
label.setText("You Won!");
disable();
} else {
insertG(method.smartMove(1, 2));
if (method.winCheck(2) == 1) {
label.setText("You Lost!");
disable();
}
}
}
//Button 8
if (event.getSource() == buttons[8]) {
buttons[8].setText("X");
buttons[8].setEnabled(false);
turncount++;
tieCheck(turncount);
method.insertArray(8, 1);
if (method.winCheck(1) == 1) {
label.setText("You Won!");
disable();
} else {
insertG(method.smartMove(1, 2));
if (method.winCheck(2) == 1) {
label.setText("You Lost!");
disable();
}
}
}
}
}
}
import java.util.*;
public class Methods {
Random rand = new Random();
Scanner scan = new Scanner(System.in);
// represents Tick-Tack-Toe Play Field
int[] board = new int[9];
// resets board array
public void reset() {
for (int i = 0; i < 9; i++) {
board[i] = 0;
}
}
// inserts player on a specific spot
public void insertArray(int spot, int player) {
board[spot] = player;
}
// for hard mode
public void expertMove(int player1, int player2) {
}
// for medium
public int smartMove(int player1, int player2) {
boolean turntaken = false;
for (int i = 0; i < 9; i++) {
if (board[i] == 0) {
board[i] = player2;
if (winCheck(player2) == 1) {
return i;
} else {
board[i] = 0;
}
}
}
for (int i = 0; i < 9; i++) {
if (board[i] == 0) {
board[i] = player1;
if (winCheck(player1) != 1) {
board[i] = 0;
} else {
board[i] = player2;
return i;
}
}
}
// If the opposite player is not about to win, then Computer goes randomly
if (turntaken == false) {
return randomMove(player2);
}
return 0;
}
// For easy mode and also utilized in smartMove() for medium mode
public int randomMove(int player) {
int rnum = 0;
rnum = rand.nextInt(8);
while (emptyCheck(rnum) != true) {
rnum = rand.nextInt(8);
}
board[rnum] = player;
return rnum;
}
//Returns 1 if player won the game
public int winCheck(int player) {
for (int ii = 0; ii <= 2; ii++) {
if (board[ii] == player && board[ii + 3] == player && board[ii + 6] == player)
return 1;
}
for (int z = 0; z <= 6; z = z + 3) {
if (board[z] == player && board[z + 1] == player && board[z + 2] == player)
return 1;
}
if (board[0] == player && board[4] == player && board[8] == player) {
return 1;
}
if (board[2] == player && board[4] == player && board[6] == player) {
return 1;
}
return 0;
}
//Returns true if tie
public boolean tieCheck() {
for(int i=0;i < 9; i++) {
if(board[i] == 0) {
board[i] = 2;
if(winCheck(1) != 1 && winCheck(2) != 1) {
return true;
}else {
board[i] = 0;
}
}
}
return false;
}
// Checks if empty: True if empty/false if taken by player
public boolean emptyCheck(int rnum) {
if (board[rnum] == 0) {
return true;
} else {
return false;
}
}
}
import java.awt.Font;
import javax.swing.JFrame;
import javax.swing.JTabbedPane;
public class Driver {
public static void main(String []args) {
JTabbedPane difficulty = new JTabbedPane();
//difficulty.addTab("Easy", new EasyPanel());
difficulty.addTab("Medium", new MediumPanel());
//difficulty.addTab("Hard", new HardPanel());
Font f = new Font("Arial", Font.PLAIN, 20);
difficulty.setFont(f);
JFrame frame = new JFrame("Tic-Tac-Toe");
frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
frame.getContentPane().add(difficulty);
frame.pack();
frame.setVisible(true);
}

On every click, you set turncount = 0:
// Checks for buttons being pressed
public void actionPerformed(ActionEvent event) {
int turncount = 0;
but in your method tieCheck:
// Checks array using tieCheck from Methods class for a tie
public void tieCheck(int turncount) {
if (turncount == 4 && method.tieCheck() == true) {
disable();
label.setText("It's a tie!");
}
}
you check if turncount == 4but it is always 1. You should change the turncount variable from local to global.
And then in method randomMove, you have an endless loop:
// For easy mode and also utilized in smartMove() for medium mode
public int randomMove(int player) {
int rnum = 0;
rnum = rand.nextInt(8);
while (emptyCheck(rnum) != true) { // <--------- HERE
rnum = rand.nextInt(8);
}

Like Peter1982 said in his answer, you should make turncount a class variable instead of a method variable so that it doesn't get reset every time you call the actionPerformed method.
To stop the game from getting frozen, you can create a boolean class variable that keeps track of if the game is over, such as gameOver. You then update gameOver in the tieCheck method, for example:
private class ButtonListener implements ActionListener {
boolean gameOver = false;
// ...
// Checks array using tieCheck from Methods class for a tie
public void tieCheck(int turncount) {
if (turncount == 4 && method.tieCheck() == true) {
gameOver = true; // <---- Update gameOver
disable();
label.setText("It's a tie!");
}
}
// Button 0
if (event.getSource() == buttons[0]) {
buttons[0].setText("X");
buttons[0].setEnabled(false);
turncount++;
tieCheck(turncount);
method.insertArray(0, 1);
if (method.winCheck(1) == 1) {
label.setText("You Won!");
disable();
} else if (!gameOver) { // <---- Check if the game is over
insertG(method.smartMove(1, 2));
if (method.winCheck(2) == 1) {
label.setText("You Lost!");
disable();
}
}
}
// ...
}
Make sure to reset turncount and tieCheck in your reset method.
Also, as an extra note, when I was looking through your code, I noticed that in your randomMove method you have the following: rnum = rand.nextInt(8);. Currently, this won't allow the computer to make a random move on the 9th button because rand.nextInt(8) will return a value of 0 through 7. This is because the 8 is exclusive. So just put 9 as the parameter like this: rand.nextInt(9) to get 0 through 8. I know it is trivial but I just wanted to point it out.

How do I implement a reset button for my GUI?

I am an AP Computer Science student and I need help with my assignment for the class. My assignment is to create a simple GUI or game using Eclipse. I made a simple player vs. player tic-tac-toe game, but I do not know how to create a "reset" button for my GUI. I tried multiple times, but I can't get it to work or show up in my GUI. I would appreciate some pointers on how to implement a functional reset button, so I would not have exit out of my GUI multiple times to start playing again. Here is the code I have written so far.
package gui;
import java.awt.*;
import java.awt.event.*;
import javax.swing.*;
public class TicTacToeGUI implements ActionListener
{
JFrame window = new JFrame("Tic-Tac-Toe");
JButton[] button;
JButton reset = new JButton("Reset");
String letter = "";
public int count = 0;
public boolean win = false;
public TicTacToeGUI()
{
button = new JButton[9];
window.setSize(300,300);
window.setLayout(new GridLayout(3,3));
JButton dummy = new JButton("");
Font font = dummy.getFont();
Font bigFont = font.deriveFont(font.getSize2D() * 5.0f);
JButton reset = new JButton("Reset");
for(int i = 0; i < 9; i++)
{
button[i] = new JButton("");
button[i].setFont(bigFont);
button[i].addActionListener(this);
window.add(button[i]);
}
window.setVisible(true);
}
public void actionPerformed(ActionEvent a)
{
count++;
if(count % 2 == 1)
{
letter = "X";
}
else
{
letter = "O";
}
Object but = a.getSource();
for(int i = 0; i < 9; i++)
{
if(but == button[i])
{
button[i].setText(letter);
button[i].setEnabled(false);
break;
}
}
if( button[0].getText() == button[1].getText() && button[1].getText() == button[2].getText() && button[0].getText() != "")
{
win = true;
}
else if(button[3].getText() == button[4].getText() && button[4].getText() == button[5].getText() && button[3].getText() != "")
{
win = true;
}
else if(button[6].getText() == button[7].getText() && button[7].getText() == button[8].getText() && button[6].getText() != "")
{
win = true;
}
else if(button[0].getText() == button[3].getText() && button[3].getText() == button[6].getText() && button[0].getText() != "")
{
win = true;
}
else if(button[1].getText() == button[4].getText() && button[4].getText() == button[7].getText() && button[1].getText() != "")
{
win = true;
}
else if(button[2].getText() == button[5].getText() && button[5].getText() == button[8].getText() && button[2].getText() != "")
{
win = true;
}
else if(button[0].getText() == button[4].getText() && button[4].getText() == button[8].getText() && button[0].getText() != "")
{
win = true;
}
else if(button[2].getText() == button[4].getText() && button[4].getText() == button[6].getText() && button[2].getText() != "")
{
win = true;
}
else
{
win = false;
}
if(win == true)
{
JOptionPane.showMessageDialog(null, letter + " WINS!");
}
else if(count == 9 && win == false)
{
JOptionPane.showMessageDialog(null, "Tie Game!");
}
}
public static void main(String[] args)
{
new TicTacToeGUI();
}
}

You might want to try this:
window.setLayout(new BorderLayout());
JPanel panel = new JPanel( new GridLayout(3, 3));
window.add(panel, BorderLayout.CENTER); // add panel to window center
window.add(reset, BorderLayout.SOUTH); // add reset button to window bottom
Of course, you will have to add your 9 buttons to panel now, not to window.
But why don't you just reset automatically after the user confirmed the dialog at the end of the game?

Reset your board after a tie or win. An example reset method. Otherwise you are going to have to make room on your Frame to hold a button to do this.
private void ResetBoard() {
for(int i = 0; i < 9; i++) {
button[i].setText("");
button[i].setEnabled(true);
count = 0;
}
}
Then use this method when a check is made to see if a player won or the game ends in a tie as below:
if(win == true)
{
JOptionPane.showMessageDialog(null, letter + " WINS!");
ResetBoard();
}
else if(count == 9 && win == false)
{
JOptionPane.showMessageDialog(null, "Tie Game!");
ResetBoard();
}

using toString from other methods

I am trying to output the information from the Salaried class in the EmployeesApplet class using the toString method in Salaried, however i keep receiving the error
EmployeesApplet.java:292: error: non-static method toString() cannot be referenced from a static context
ta.append(Salaried.toString());
^
How do i get around this error to display the information correctly?
here is the Salaried class
public class Salaried extends Employee
{
private double weekly_salary;
public Salaried(String first_name, String last_name, int e, double w ) // one constructor
{
super(first_name,last_name, e);
weekly_salary = w;
}
public String toString()
{
return super.toString() + " \nWeekly Salary" + weekly_salary ;
} // toString method
}
and here is the EmployeesApplet class
import javax.swing.*;
import java.awt.*;
import java.awt.event.*;
public class EmployeesApplet extends JApplet implements ActionListener
{
public JButton sd = new JButton ("Salaried");
public JButton hr = new JButton ("Hourly");
public JButton cm = new JButton ("Commissioned");
public JButton cl = new JButton ("Clear");
private final int FIELDS = 8,
FIELD_WIDTH = 20;
private String[] strings = new String[FIELDS];
private TextFieldWithLabel[] tf = new TextFieldWithLabel[FIELDS];
private JTextArea ta = new JTextArea(5,25);
String[] s = {"First Name", "Last Name", "Employee ID", "(a) Salaried: Weekly Salary", "(b1) Hourly 1: Rate Per Hour",
"(b2) Hourly 2: Hours Worked" , "(c1) Commissioned: Rate", "(c2) Commissioned: Gross Sales" };
public void init()
{
this.setSize(420, 310);
//----------------------
// Set up the Structure
//----------------------
Container c = getContentPane();
JPanel f = new JPanel(new FlowLayout());
JPanel b = new JPanel(new BorderLayout(2,0));
JPanel glb = new JPanel(new GridLayout(8,1,0,2));
JPanel gtf = new JPanel(new GridLayout(8,1,0,2));
JPanel flb = new JPanel(new FlowLayout());
// Add FlowLayout to the container
c.add(f);
// Add BorderLayout to the FlowLayout
f.add(b);
//---------------------------------------
//Add JPanels to the BorderLayout regions
//---------------------------------------
// Add JLables to GridLayout in West
b.add(glb, BorderLayout.WEST);
for (int i = 0; i < tf.length; i++)
{
tf[i] = new TextFieldWithLabel(s[i], FIELD_WIDTH);
glb.add(tf[i].getLabel());
}
// Add JTextFeilds to GridLayout in East
b.add(gtf, BorderLayout.EAST);
for (int i = 0; i < tf.length; i++)
{
tf[i] = new TextFieldWithLabel(s[i], FIELD_WIDTH);
tf[i].getTextField();
gtf.add(tf[i].getTextField());
}
// Add JButtons to FlowLayout in South
b.add(flb, BorderLayout.SOUTH);
flb.add(sd);
flb.add(hr);
flb.add(cm);
flb.add(cl);
sd.addActionListener(this);
hr.addActionListener(this);
cm.addActionListener(this);
cl.addActionListener(this);
// Add JTextArea and make it not editable
f.add(ta);
ta.setEditable(false);
}
//---------------------------------------
// Read all the JTextFields and
// save the contents in a parallel array
//---------------------------------------
private void readFields()
{
for (int i = 0; i < tf.length; i++) // or FIELDS
strings[i] = tf[i].getText();
}
private boolean fieldsExist(int i, int i2)
{
if(i == 0 && i2 == 3) // Checks Salaried worker
{
if(tf[0].getText() == null || tf[0].getText().length() == 0)
{
showStatus("First Name field is empty"); // Diplays error message in status area
tf[0].getTextField().requestFocus(); // Places focus in JTextField
return false;
}
else if(tf[1].getText() == null || tf[1].getText().length() == 0)
{
showStatus("Last Name field is empty");
tf[1].getTextField().requestFocus();
return false;
}
else if(tf[2].getText() == null || tf[2].getText().length() == 0)
{
showStatus("Employee ID field is empty");
tf[2].getTextField().requestFocus();
return false;
}
else if(tf[3].getText() == null || tf[3].getText().length() == 0)
{
showStatus("(a)Salried: Weekly Salary field is empty");
tf[3].getTextField().requestFocus();
return false;
}
else
return true;
}
if(i == 0 && i2 == 2) // Checks Hourly worker
{
if(tf[0].getText() == null || tf[0].getText().length() == 0)
{
showStatus("First Name field is empty");
tf[0].getTextField().requestFocus();
return false;
}
else if(tf[1].getText() == null || tf[1].getText().length() == 0)
{
showStatus("Last Name field is empty");
tf[1].getTextField().requestFocus();
return false;
}
else if(tf[2].getText() == null || tf[2].getText().length() == 0)
{
showStatus("Employee ID field is empty");
tf[2].getTextField().requestFocus();
return false;
}
else
return true;
}
if(i == 4 && i2 == 5) // Checks Hourly worker the second time
{
if(tf[4].getText() == null || tf[4].getText().length() == 0)
{
showStatus("(b1) Hourly 1: Rate Per Hour field is empty");
tf[5].getTextField().requestFocus();
return false;
}
else if(tf[5].getText() == null || tf[5].getText().length() == 0)
{
showStatus("(b2) Hourly 2: Hours Worked field is empty");
tf[5].getTextField().requestFocus();
return false;
}
else
return true;
}
if(i == 0 && i2 == 2) // Checks Commissioned worker
{
if(tf[0].getText() == null || tf[0].getText().length() == 0)
{
showStatus("First Name field is empty");
tf[0].getTextField().requestFocus();
return false;
}
else if(tf[1].getText() == null || tf[1].getText().length() == 0)
{
showStatus("Last Name field is empty");
tf[1].getTextField().requestFocus();
return false;
}
else if(tf[2].getText() == null || tf[2].getText().length() == 0)
{
showStatus("Employee ID field is empty");
tf[2].getTextField().requestFocus();
return false;
}
else
return true;
}
if(i == 6 && i2 == 7) // Checks Commissioned second time
{
if(tf[6].getText() == null || tf[6].getText().length() == 0)
{
showStatus("(c1)Commissioned: Rate field is empty");
tf[0].getTextField().requestFocus();
return false;
}
else if(tf[7].getText() == null || tf[7].getText().length() == 0)
{
showStatus("(c2)Commissioned: Ratefield is empty");
tf[1].getTextField().requestFocus();
return false;
}
else
return true;
}
return false;
}
private boolean fieldsEmpty(int i, int i2, String[] a)
{
if(i == 4 && i2 == 7) // checks salaried
{
for (int index = 4; index <= 7; index++)
{
if(tf[index].getText().length() != 0)
{
showStatus( a[index] + " should be empty"); // Diplays error message in status area
tf[index].getTextField().requestFocus(); // Places focus in JTextField
return true;
}
else return false;
} // end for
} // end if
if (i == 3 && i2 == 3) // checks hourly first time
{
if(tf[3].getText().length() != 0)
{
showStatus(a[3] + " field should be empty");
tf[3].getTextField().requestFocus();
return true;
}
} // end if
if(i == 6 && i2 == 7) // checks hourly second time
{
for (int index = 6; index <= 7; index++)
{
if(tf[index].getText().length() != 0)
{
showStatus(a[index] + " field should be empty");
tf[index].getTextField().requestFocus();
return true;
}
} // end for
} // end if
if(i == 3 && i2 == 5) // checks commissioned
{
for (int index = 3; index <= 5; index++)
{
if(tf[index].getText().length() != 0)
{
showStatus(a[index] + " field should be empty");
tf[index].getTextField().requestFocus();
return true;
}
} // end for
} // end if
return false;
}
public void actionPerformed(ActionEvent e)
{
showStatus("");
if (e.getSource() == cl) // Executes clear button is clicked
{
for (int i = 0; i < FIELDS; i++)
{
tf[i].getTextField().setText("");
tf[0].getTextField().requestFocus();
}
} // End clear if
if (e.getSource() != cl)
{
if(e.getSource() == sd) // checks for salaried employee
{
showStatus("Salaried");
fieldsExist(0,3);
fieldsEmpty(4,7, s);
ta.append(Salaried.toString());
} // end salaried
if(e.getSource() == hr) // checks for hourly employee
{
showStatus("Hourly");
fieldsExist(0,2);
fieldsExist(4,5);
fieldsEmpty(3,3, s);
fieldsEmpty(6,7, s);
} // end hourly
if(e.getSource() == cm) // checks for commissioned employee
{
showStatus("Commissioned");
fieldsExist(0,2);
fieldsExist(6,7);
fieldsEmpty(3,5, s);
} // end commisssioned
} // end if
} // End of actionPerformed
}

As the error states, toString() is not static, you need to run it on an instance of Salaried. e.g.
Salaried s = new Salaried();
s.toString(); // should work...
Without relevant section from EmployeeApplet I cannot advise further, note ta.append(Salaried.toString()); in the error message you posted, does not appear to correspond to fragment of EmployeeApplet you gave...

Minimax algorithm always returns one number

I have got a problem with minimax algorithm. I want to make tic tac toe game with AI. I used JFrame to make that.
So my minimax algorithm returns always number 9 and I don't know why. What's wrong ?
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.JOptionPane;
public class Zadanie2 extends JFrame implements ActionListener {
/**
*
*/
JButton button0 = new JButton("");
JButton button1 = new JButton("");
JButton button2 = new JButton("");
JButton button3 = new JButton("");
JButton button4 = new JButton("");
JButton button5 = new JButton("");
JButton button6 = new JButton("");
JButton button7 = new JButton("");
JButton button8 = new JButton("");
JButton button9 = new JButton("");
int playerSign = 1;
String computerMark, opponentMark;
public static final long serialVersionUID = 1L;
JButton[] buttonArray = { button0, button1, button2, button3, button4,
button5, button6, button7, button8, button9 };
Object[] options = { "GRAJ OD NOWA", "ZAKOŃCZ GRĘ" };
Object[] startOptions = { "GRACZ", "KOMPUTER", "OPUŚĆ GRĘ" };
boolean canMove;
boolean computerStarted;
int bb = 1;
public Zadanie2() {
super("KÓŁKO I KRZYŻYK");
setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
setSize(300, 300);
setResizable(false);
setLocation(470,400);
setLayout(new GridLayout(3,3));
for(int i = 1; i <= 9; i++){
add(add(buttonArray[i]));
buttonArray[i].addActionListener(this);
}
setVisible(true);
int y = JOptionPane.showOptionDialog(null,"WYBIERZ KTO MA ZACZĄĆ GRĘ","WIADOMOŚĆ", JOptionPane.INFORMATION_MESSAGE,
JOptionPane.INFORMATION_MESSAGE,
null,
startOptions,
startOptions[0]);
if (y == 2) {
System.exit(1);
}
if (y == 1) { // COMPUTER
computerStarted = true;
computerMark = "X";
opponentMark = "O";
canMove = true;
computerMove();
}
if (y == 0) { // PLAYER
computerStarted = false;
computerMark = "O";
opponentMark = "X";
}
}
public static void main(String[] args) {
new Zadanie2();
}
public void close() {
playerSign = 1;
dispose();
}
private void computerMove() {
if(canMove){
System.out.println("AI: "+AI(buttonArray));
buttonArray[AI(buttonArray)].doClick();
}
canMove = false;
}
private int AI(JButton[] buttonArray2){
int ruch, i, m, mmx;
ruch = 0;
mmx = -10;
for(i = 1; i < 9; i++)
if(buttonArray[i].getText() == "");
{
buttonArray[i].setText(computerMark);
m = minimax(buttonArray, computerMark);
buttonArray[i].setText("");
if (m > mmx) {
mmx = m;
ruch = i;
}
}
return ruch;
}
public int minimax(JButton[] buttonArray,String gracz){
int m, mmx;
if(win(buttonArray,gracz)) return (gracz == computerMark) ? 1 : -1;
if(tie(buttonArray)){
return 0;}
gracz = (gracz == computerMark) ? opponentMark : computerMark;
mmx = (gracz == opponentMark) ? 10 : -10;
for(int i = 1; i <= 9; i++)
if(buttonArray[i].getText() == "")
{
buttonArray[i].setText(gracz);
m = minimax(buttonArray,gracz);
buttonArray[i].setText("");
if(((gracz == opponentMark) && (m < mmx)) || ((gracz == computerMark) && (m > mmx))){mmx = m;}
}
return mmx;
}
private void checkWin() {
if(win(buttonArray,"X")){
winX();
}
if(win(buttonArray,"O")){
winO();
}
if(tie(buttonArray)){
sayTie();
}
}
private void winX() {
int n = JOptionPane.showOptionDialog(null, "WYGRAŁ GRACZ X ",
"WIADOMOŚĆ", JOptionPane.INFORMATION_MESSAGE,
JOptionPane.INFORMATION_MESSAGE, null, options, options[0]);
if (n == 0) {
close();
new Zadanie2();
}
if (n == 1) {
System.exit(1);
}
dispose();
}
private void winO() {
int n = JOptionPane.showOptionDialog(null, "WYGRAŁ GRACZ O ",
"WIADOMOŚĆ", JOptionPane.INFORMATION_MESSAGE,
JOptionPane.INFORMATION_MESSAGE, null, options, options[0]);
if (n == 0) {
close();
new Zadanie2();
}
if (n == 1) {
System.exit(1);
}
dispose();
}
private void sayTie() {
int n = JOptionPane.showOptionDialog(null, "REMIS! ", "WIADOMOŚĆ",
JOptionPane.INFORMATION_MESSAGE,
JOptionPane.INFORMATION_MESSAGE, null, options, options[0]);
if (n == 0) {
close();
new Zadanie2();
}
if (n == 1) {
System.exit(1);
}
dispose();
}
public boolean tie(JButton[] buttonArray2){
for(int i = 1; i <= 9; i++){
if(buttonArray2[i].getText() == ""){
return false;
}
}
return true;
}
private boolean win(JButton[] buttonArray2, String g) {
if (buttonArray2[1].getText() == buttonArray2[2].getText()
&& buttonArray2[1].getText() == buttonArray2[3].getText()
&& buttonArray2[2].getText() == buttonArray2[3].getText() && buttonArray2[1].getText() == g) {
return true;
}
if (buttonArray2[3].getText() == buttonArray2[7].getText()
&& buttonArray2[3].getText() == buttonArray2[5].getText()
&& buttonArray2[7].getText() == buttonArray2[5].getText() && buttonArray2[3].getText() == g) {
return true;
}
if (buttonArray2[7].getText() == buttonArray2[8].getText()
&& buttonArray2[7].getText() == buttonArray2[9].getText()
&& buttonArray2[8].getText() == buttonArray2[7].getText() && buttonArray2[7].getText() == g) {
return true;
}
if (buttonArray2[4].getText() == buttonArray2[5].getText()
&& buttonArray2[4].getText() == buttonArray2[6].getText()
&& buttonArray2[5].getText() == buttonArray2[6].getText() && buttonArray2[4].getText() == g) {
return true;
}
if (buttonArray2[1].getText() == buttonArray2[5].getText()
&& buttonArray2[1].getText() == buttonArray2[9].getText()
&& buttonArray2[5].getText() == buttonArray2[9].getText() && buttonArray2[1].getText() == g) {
return true;
}
if (buttonArray2[1].getText() == buttonArray2[4].getText()
&& buttonArray2[1].getText() == buttonArray2[7].getText()
&& buttonArray2[4].getText() == buttonArray2[7].getText() && buttonArray2[1].getText() == g) {
return true;
}
if (buttonArray2[2].getText() == buttonArray2[8].getText()
&& buttonArray2[2].getText() == buttonArray2[5].getText()
&& buttonArray2[8].getText() == buttonArray2[5].getText() && buttonArray2[2].getText() == g) {
return true;
}
if (buttonArray2[3].getText() == buttonArray2[6].getText()
&& buttonArray2[3].getText() == buttonArray2[9].getText()
&& buttonArray2[6].getText() == buttonArray2[9].getText() && buttonArray2[3].getText() == g) {
return true;
}
return false;
};
#Override
public void actionPerformed(ActionEvent e) {
Object source = e.getSource();
for (int i = 1; i <= 9; i++) {
if (source == buttonArray[i] ) {
playerSign++;
if (playerSign % 2 == 0 && buttonArray[i].getText() == "") {
buttonArray[i].setText("X");
}
if (playerSign % 2 != 0 && buttonArray[i].getText() == "") {
buttonArray[i].setText("O");
}
if (computerStarted && playerSign % 2 != 0) {
canMove = true;
computerMove();
}
if (!computerStarted && playerSign % 2 == 0) {
canMove = true;
computerMove();
}
}
}
System.out.println("PS: " + playerSign);
if(playerSign > 3){
checkWin();}
}
}
Any ideas on how I may solve this problem?

You should use .equals instead of == whenever you compare two Objects.
E.g. there should be computerMark.equals(gracz) instead of gracz == computerMark.
Edit:
Also, You should replace 1 and -1 with 10 and -10 respectively here:
if(win(buttonArray,gracz)) return (gracz == computerMark) ? 1 : -1;
Reference

java.lang.reflect.invocationtargetexception error when placing applet onto website

I'm having trouble getting my applet to run on my website. It's my first time embedding an applet to a website and I have no idea what is going wrong.
I created the .jar file following the following website's instructions:https://eyeasme.com/Shayne/HTML5_APPLETS/
And here is the code for the java applet.
import java.awt.*;
import java.awt.event.*;
import javax.swing.*;
import java.util.Random;
public class TicTacToe extends JFrame
{
private JButton button [][] = new JButton [3][1];
private boolean checkerO [][] = new boolean [3][2];
private boolean checkerX [][] = new boolean [3][3];
private JPanel panel;
private final int WINDOW_WIDTH = 200;
private final int WINDOW_HEIGHT = 200;
private int turn = 1;
public TicTacToe()
{
setTitle ("Tic-Tac-Toe");
setSize (WINDOW_WIDTH,WINDOW_HEIGHT);
setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
//create and register an event listener with all buttons
for(int i = 0; i <= 2; i++)
{
for(int j = 0; j <= 2; j++)
{
button [i][j] = new JButton();
button [i][j].addActionListener(new ButtonListener());
button [i][j].setFont(new Font("Arial", Font.PLAIN, 35));
}
}
for(int i = 0; i <= 2; i++)
{
for(int j = 0; j <= 2; j++)
{
checkerO [i][j] = false;
}
}
for(int i = 0; i <= 2; i++)
{
for(int j = 0; j <= 2; j++)
{
checkerX [i][j] = false;
}
}
//create a panel, work on the layout and add the buttons
panel = new JPanel();
GridLayout myLayout = new GridLayout(3,3);
panel.setLayout(myLayout);
for (int i = 0; i <= 2; i++)
{
for(int j = 0; j <= 2; j++)
{
panel.add(button[i][j]);
}
}
//add panel to content pane
add(panel);
//display window
setVisible(true);
}
private class ButtonListener implements ActionListener
{
public void actionPerformed (ActionEvent e)
{
//determine which button is clicked
for (int i = 0; i <= 2; i++)
{
for (int j = 0; j <= 2; j++)
{
if (e.getSource() == button[i][j])
{
//Check if the chosen button has already been picked.
if (checkerX[i][j] || checkerO[i][j])
{
JOptionPane.showMessageDialog(null, "I'm sorry, Dave. I'm afraid I can't do that.");
}
else if (turn == 1 || turn == 3 || turn == 5 || turn == 7 || turn == 9)
{
button[i][j].setText("X");
checkerX[i][j] = true;
turn++;
}
//Checks all possible combinations for X to see if X won
if ((checkerX[0][0] == true && checkerX[0][4] == true && checkerX[0][5] == true) || (checkerX[1][0] == true && checkerX[1][6] == true && checkerX[1][7] == true) || (checkerX[2][0] == true && checkerX[2][8] == true && checkerX[2][9] == true) || (checkerX[0][0] == true && checkerX[1][0] == true && checkerX[2][0] == true) || (checkerX[0][10] == true && checkerX[1][11] == true && checkerX[2][12] == true) || (checkerX[0][13] == true && checkerX[1][14] == true && checkerX[2][15] == true) || (checkerX[0][0] == true && checkerX[1][16] == true && checkerX[2][17] == true) || (checkerX[0][18] == true && checkerX[1][19] == true && checkerX[2][0] == true))
{
JOptionPane.showMessageDialog(null, "X wins the game.");
System.exit(0);
}
//If X hasn't won, run the AI
runAI();
//If turn goes past 9, it means it's a tie
if (turn == 10)
{
JOptionPane.showMessageDialog(null, "It's a tie.");
System.exit(0);
}
}
}
}
}
public void runAI()
{
Random generator = new Random();
boolean picked = false;
if (turn == 2 || turn == 4 || turn == 6 || turn == 8)
{
while (picked == false)
{
int position1 = generator.nextInt(3);
int position2 = generator.nextInt(3);
//If the position is already picked, the AI will roll a random number again.
if (checkerX[position1][position2] || checkerO[position1][position2])
{
}
//If the position is empty, put an O.
else
{
button[position1][position2].setText("O");
checkerO[position1][position2] = true;
turn++;
picked = true;
}
}
}
//Checks all possible combinations for O to see if O won
if ((checkerO[0][0] == true && checkerO[0][20] == true && checkerO[0][21] == true) || (checkerO[1][0] == true && checkerO[1][22] == true && checkerO[1][23] == true) || (checkerO[2][0] == true && checkerO[2][24] == true && checkerO[2][25] == true) || (checkerO[0][0] == true && checkerO[1][0] == true && checkerO[2][0] == true) || (checkerO[0][26] == true && checkerO[1][27] == true && checkerO[2][28] == true) || (checkerO[0][29] == true && checkerO[1][30] == true && checkerO[2][31] == true) || (checkerO[0][0] == true && checkerO[1][32] == true && checkerO[2][33] == true) || (checkerO[0][34] == true && checkerO[1][35] == true && checkerO[2][0] == true))
{
JOptionPane.showMessageDialog(null, "O wins the game.");
System.exit(0);
}
}
}
public static void main (String [] args)
{
TicTacToe ttt = new TicTacToe();
}
}
There was a bit of a formatting problem when I tried to paste this on here so there might be some typos in the code. But the program actually runs as a .exe file.
Here's the HTML code:
<html>
<head>
<title>Minigames for All</title>
<link rel="stylesheet" type="text/css" href="style.css">
</head>
<body>
<h2 id="header">Welcome to Minigames for All.</h2>
<hr>
<object type="application/x-java-applet" height="300" width="550">
<param name="code" value="TicTacToe" />
<param name="archive" value="applet/TicTacToe.jar" />
Applet failed to run. No Java plug-in was found.
</object>
<hr>
<table>
<tbody>
<tr>
<td><a href="rps.html">Rock, Paper, Scissors</td>
<td><a href="random.html">Guess the Number</td>
<td><a href="ttt.html">Tic Tac Toe</td>
</tr>
<tr>
<td><a href="flip.html">Flip a Coin</td>
<td><a href="rpg.html">Slime RPG</td>
<td><a href="shoot.html">Space Shooter</td>
</tr>
<tr>
<td>&nbsp</td>
<td><a href="index.html">Home Page</td>
<td>&nbsp</td>
</tr>
</tbody>
</table>
</body>
</html>
Manifest file:
Manifest-Version: 1.0
Created-By: 1.7.0_21 (Oracle Corporation)
Error Message:http://puu.sh/5J4z1.png

The first thing I notice is this
TicTacToe extends JFrame
not
TicTacToe extends JApplet // or even Applet.
Are you sure you have an Applet?