Recursion error in GUI - java

I am creating a simple 9x9 grid for Minesweeper. One of the primary functions of this game is to have a recursion to check all the sides when the tile clicked has no bombs surrounding it. In the code attached below, I have been able to create a function that checks the upper and left side of the tile. If I add more directions, such as lower and right side, the program will crash and will not properly display the tiles. (Check the method countBorders under the line //MY MAIN PROBLEM)
//displays the main GUI
package Minesweeper4;
public class mainFrame {
public static void main(String[] args) {
new Grid().setVisible(true);
}
}
// the main code
package Minesweeper4;
import java.awt.*;
import java.awt.event.ActionEvent;
import java.awt.event.ActionListener;
import java.util.ArrayList;
import java.util.Random;
import javax.swing.*;
public class Grid extends JFrame implements ActionListener {
private JPanel mainGrid;
private JButton button1, button2;
private JButton[][] buttons = new JButton[9][9];
private String[][] mines = new String[9][9];
private ArrayList<ParentSquare> parentSquare = new ArrayList<ParentSquare>();
Random rand = new Random();
NumberSquare numberSquare = new NumberSquare();
MineSquare mineSquare = new MineSquare();
public void addMines() {
for (int j = 0; j < 9; j++) {
for (int k = 0; k < 9; k++) {
mines[j][k] = ".";
}
}
for (int i = 0; i < 3; i++) {
int temp_x = rand.nextInt(9);
int temp_y = rand.nextInt(9);
mines[temp_x][temp_y] = "x";
}
}
public void showMines() {
for (int x = 0; x < 9; x++) {
for (int y = 0; y < 9; y++) {
String temp = mines[x][y];
if (temp.equals("x")) {
System.out.println("X: " + (x + 1) + " Y: " + (y + 1) + " Value: " + temp);
}
}
}
}
public Grid() {
this.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
this.setSize(500, 500);
this.setTitle("Minesweeper 1.0");
mainGrid = new JPanel();
mainGrid.setLayout(new GridLayout(9, 9));
this.add(mainGrid);
button1 = new JButton("Boop");
button2 = new JButton("Poop");
for (int i = 0; i < 9; i++) {
for (int j = 0; j < 9; j++) {
buttons[i][j] = new JButton("");
buttons[i][j].addActionListener(this);
buttons[i][j].setBackground(Color.GRAY);
}
}
for (int k = 0; k < 9; k++) {
for (int l = 0; l < 9; l++) {
mainGrid.add(buttons[k][l]);
}
}
addMines();
showMines();
}
public void countBorders(int x, int y) {
int UL = 0, UU = 0, UR = 0, LL = 0, RR = 0, DL = 0, DD = 0, DR = 0, SUM = 0;
if (x > 0) {
UU = checkTile(x - 1, y);
}
if (y > 0) {
LL = checkTile(x, y - 1);
}
if (y < 8) {
RR = checkTile(x, y + 1);
}
if (x < 8) {
DD = checkTile(x + 1, y);
}
if ((x > 0) && (y > 0)) {
UL = checkTile(x - 1, y - 1);
}
if ((x > 0) && (y < 8)) {
UR = checkTile(x - 1, y + 1);
}
if ((x < 8) && (y > 0)) {
DL = checkTile(x + 1, y - 1);
}
if ((x < 8) && (y < 8)) {
DR = checkTile(x + 1, y + 1);
}
SUM = UL + UU + UR + LL + RR + DL + DD + DR;
printTile(x, y, SUM);
if (SUM == 0) { //MY MAIN PROBLEM
// if ((x > 0) && (y > 0)) {countBorders(x-1, y-1);} //Upper left
if (x > 0) {
countBorders(x - 1, y);
} //Upper
// if ((x > 0) && (y < 8)) {countBorders(x-1, y+1);} //Upper right
if (y > 0) {
countBorders(x, y - 1);
} //Left
// if (y < 8) {countBorders(x, y+1);} //Right
// if ((x < 8) && (y > 0)) {countBorders(x+1, y-1);} //Down Left
// if (x < 8) {countBorders(x+1, y);} //Down
// if ((x < 8) && (y < 8)) {countBorders(x+1, y+1);} //Down Right
}
}
public void printTile(int x, int y, int SUM) {
String text = Integer.toString(SUM);
buttons[x][y].setText(text);
buttons[x][y].setBackground(Color.CYAN);
}
public int checkTile(int x, int y) {
String c = mines[x][y];
if (c.equals("x")) {
return 1;
} else {
return 0;
}
}
public void click(int x, int y) {
String mine = mines[x][y];
if (mine.equals("x")) {
System.out.println("Bomb!!!");
buttons[x][y].setText("!");
buttons[x][y].setBackground(Color.RED);
} else {
countBorders(x, y);
System.out.println("Safe!!!");
// buttons[x][y].setText("√");
// buttons[x][y].setBackground(Color.WHITE);
}
}
#Override
public void actionPerformed(ActionEvent e) {
for (int i = 0; i < 9; i++) {
for (int j = 0; j < 9; j++) {
if (e.getSource() == buttons[i][j]) {
System.out.println("Clicked Tile X: " + (i + 1) + " Y: " + (j + 1));
//buttons[i][j].setText("!");
click(i, j);
}
}
}
}
}
Is there a way on how to fix this recursion problem?
Thank you in advance and I'm really trying to learn Java. Have a nice day!

Your error-causing recursion has no stopping logic that I can find, and what you need to do is to somehow check to make sure that a cell hasn't already been counted or pressed before re-counting it. Otherwise the code risks throwing a stackoverflow error. This will require giving the cells being counted some state that would tell you this information, that would tell you if the cell has already been counted.
For an example of a successful program that does this logic, feel free to look at my Swing GUI example, one I created 5 years ago. In this code, I've got a class, MineCellModel, that provides the logic (not the GUI) for a single mine sweeper cell, and the class contains a boolean field, pressed, that is false until the cell is "pressed", either by the user pressing the equivalent button, or recursively in the model's logic. If the cell is pressed, if the boolean is true, the recursion stops with this cell.
You can find the code here: Minesweeper Action Events. It's an old program, and so I apologize for any concepts or code that may be off.
Running the code results in this:
Here's the code present in a single file:
import java.awt.CardLayout;
import java.awt.Color;
import java.awt.Dimension;
import java.awt.Font;
import java.awt.GridLayout;
import java.awt.Insets;
import java.awt.event.ActionEvent;
import java.awt.event.ActionListener;
import java.awt.event.KeyEvent;
import java.awt.event.MouseAdapter;
import java.awt.event.MouseEvent;
import java.beans.PropertyChangeEvent;
import java.beans.PropertyChangeListener;
import java.util.ArrayList;
import java.util.Collections;
import java.util.List;
import javax.swing.BoxLayout;
import javax.swing.JButton;
import javax.swing.JFrame;
import javax.swing.JLabel;
import javax.swing.JOptionPane;
import javax.swing.JPanel;
import javax.swing.JSeparator;
import javax.swing.SwingConstants;
import javax.swing.event.SwingPropertyChangeSupport;
#SuppressWarnings("serial")
public class MineSweeper {
private JPanel mainPanel = new JPanel();
private MineCellGrid mineCellGrid;
private JButton resetButton = new JButton("Reset");
public MineSweeper(int rows, int cols, int mineTotal) {
mainPanel.setLayout(new BoxLayout(mainPanel, BoxLayout.PAGE_AXIS));
mineCellGrid = new MineCellGrid(rows, cols, mineTotal);
resetButton.setMnemonic(KeyEvent.VK_R);
resetButton.addActionListener(new ActionListener() {
public void actionPerformed(ActionEvent e) {
mineCellGrid.reset();
}
});
mainPanel.add(mineCellGrid);
mainPanel.add(new JSeparator());
mainPanel.add(new JPanel() {
{
add(resetButton);
}
});
}
private JPanel getMainPanel() {
return mainPanel;
}
private static void createAndShowUI() {
JFrame frame = new JFrame("MineSweeper");
// frame.getContentPane().add(new MineSweeper(20, 20,
// 44).getMainPanel());
frame.getContentPane().add(new MineSweeper(12, 12, 13).getMainPanel());
frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
frame.pack();
frame.setLocationRelativeTo(null);
frame.setVisible(true);
}
public static void main(String[] args) {
java.awt.EventQueue.invokeLater(new Runnable() {
public void run() {
createAndShowUI();
}
});
}
}
#SuppressWarnings("serial")
class MineCellGrid extends JPanel {
private MineCellGridModel model;
private List<MineCell> mineCells = new ArrayList<MineCell>();
public MineCellGrid(final int maxRows, final int maxCols, int mineNumber) {
model = new MineCellGridModel(maxRows, maxCols, mineNumber);
setLayout(new GridLayout(maxRows, maxCols));
for (int row = 0; row < maxRows; row++) {
for (int col = 0; col < maxCols; col++) {
MineCell mineCell = new MineCell(row, col);
add(mineCell);
mineCells.add(mineCell);
model.add(mineCell.getModel(), row, col);
}
}
reset();
}
public void reset() {
model.reset();
for (MineCell mineCell : mineCells) {
mineCell.reset();
}
}
}
class MineCellGridModel {
private MineCellModel[][] cellModelGrid;
private List<Boolean> mineList = new ArrayList<Boolean>();
private CellModelPropertyChangeListener cellModelPropChangeListener = new CellModelPropertyChangeListener();
private int maxRows;
private int maxCols;
private int mineNumber;
private int buttonsRemaining;
public MineCellGridModel(final int maxRows, final int maxCols, int mineNumber) {
this.maxRows = maxRows;
this.maxCols = maxCols;
this.mineNumber = mineNumber;
for (int i = 0; i < maxRows * maxCols; i++) {
mineList.add((i < mineNumber) ? true : false);
}
cellModelGrid = new MineCellModel[maxRows][maxCols];
buttonsRemaining = (maxRows * maxCols) - mineNumber;
}
public void add(MineCellModel model, int row, int col) {
cellModelGrid[row][col] = model;
model.addPropertyChangeListener(cellModelPropChangeListener);
}
public void reset() {
buttonsRemaining = (maxRows * maxCols) - mineNumber;
// randomize the mine location
Collections.shuffle(mineList);
// reset the model grid and set mines
for (int r = 0; r < cellModelGrid.length; r++) {
for (int c = 0; c < cellModelGrid[r].length; c++) {
cellModelGrid[r][c].reset();
cellModelGrid[r][c].setMined(mineList.get(r * cellModelGrid[r].length + c));
}
}
// advance value property of all neighbors of a mined cell
for (int r = 0; r < cellModelGrid.length; r++) {
for (int c = 0; c < cellModelGrid[r].length; c++) {
if (cellModelGrid[r][c].isMined()) {
int rMin = Math.max(r - 1, 0);
int cMin = Math.max(c - 1, 0);
int rMax = Math.min(r + 1, cellModelGrid.length - 1);
int cMax = Math.min(c + 1, cellModelGrid[r].length - 1);
for (int row2 = rMin; row2 <= rMax; row2++) {
for (int col2 = cMin; col2 <= cMax; col2++) {
cellModelGrid[row2][col2].incrementValue();
}
}
}
}
}
}
private class CellModelPropertyChangeListener implements PropertyChangeListener {
public void propertyChange(PropertyChangeEvent evt) {
MineCellModel model = (MineCellModel) evt.getSource();
int row = model.getRow();
int col = model.getCol();
if (evt.getPropertyName().equals(MineCellModel.BUTTON_PRESSED)) {
if (cellModelGrid[row][col].isMineBlown()) {
mineBlown();
} else {
buttonsRemaining--;
if (buttonsRemaining <= 0) {
JOptionPane.showMessageDialog(null, "You've Won!!!", "Congratulations",
JOptionPane.PLAIN_MESSAGE);
}
if (cellModelGrid[row][col].getValue() == 0) {
zeroValuePress(row, col);
}
}
}
}
private void mineBlown() {
for (int r = 0; r < cellModelGrid.length; r++) {
for (int c = 0; c < cellModelGrid[r].length; c++) {
MineCellModel model = cellModelGrid[r][c];
if (model.isMined()) {
model.setMineBlown(true);
}
}
}
}
private void zeroValuePress(int row, int col) {
int rMin = Math.max(row - 1, 0);
int cMin = Math.max(col - 1, 0);
int rMax = Math.min(row + 1, cellModelGrid.length - 1);
int cMax = Math.min(col + 1, cellModelGrid[row].length - 1);
for (int row2 = rMin; row2 <= rMax; row2++) {
for (int col2 = cMin; col2 <= cMax; col2++) {
cellModelGrid[row2][col2].pressedAction();
}
}
}
}
}
#SuppressWarnings("serial")
class MineCell extends JPanel {
private static final String LABEL = "label";
private static final String BUTTON = "button";
private static final int PS_WIDTH = 24;
private static final int PS_HEIGHT = PS_WIDTH;
private static final float LABEL_FONT_SIZE = (float) (24 * PS_WIDTH) / 30f;
private static final float BUTTON_FONT_SIZE = (float) (14 * PS_WIDTH) / 30f;
private JButton button = new JButton();
private JLabel label = new JLabel(" ", SwingConstants.CENTER);
private CardLayout cardLayout = new CardLayout();
private MineCellModel model;
public MineCell(final boolean mined, int row, int col) {
model = new MineCellModel(mined, row, col);
model.addPropertyChangeListener(new MyPCListener());
label.setFont(label.getFont().deriveFont(Font.BOLD, LABEL_FONT_SIZE));
button.setFont(button.getFont().deriveFont(Font.PLAIN, BUTTON_FONT_SIZE));
button.setMargin(new Insets(1, 1, 1, 1));
setLayout(cardLayout);
add(button, BUTTON);
add(label, LABEL);
button.addActionListener(new ActionListener() {
public void actionPerformed(ActionEvent e) {
pressedAction();
}
});
button.addMouseListener(new MouseAdapter() {
#Override
public void mousePressed(MouseEvent e) {
if (e.getButton() == MouseEvent.BUTTON3) {
model.upDateButtonFlag();
}
}
});
}
public MineCell(int row, int col) {
this(false, row, col);
}
#Override
public Dimension getPreferredSize() {
return new Dimension(PS_WIDTH, PS_HEIGHT);
}
public void pressedAction() {
if (model.isFlagged()) {
return;
}
model.pressedAction();
}
public void showCard(String cardConstant) {
cardLayout.show(this, cardConstant);
}
// TODO: have this change the button's icon
public void setFlag(boolean flag) {
if (flag) {
button.setBackground(Color.yellow);
button.setForeground(Color.red);
button.setText("f");
} else {
button.setBackground(null);
button.setForeground(null);
button.setText("");
}
}
private void setMineBlown(boolean mineBlown) {
if (mineBlown) {
label.setBackground(Color.red);
label.setOpaque(true);
showCard(LABEL);
} else {
label.setBackground(null);
}
}
public MineCellModel getModel() {
return model;
}
public void addPropertyChangeListener(PropertyChangeListener listener) {
model.addPropertyChangeListener(listener);
}
public void removePropertyChangeListener(PropertyChangeListener listener) {
model.removePropertyChangeListener(listener);
}
private class MyPCListener implements PropertyChangeListener {
public void propertyChange(PropertyChangeEvent evt) {
String propName = evt.getPropertyName();
if (propName.equals(MineCellModel.MINE_BLOWN)) {
setMineBlown(true);
} else if (propName.equals(MineCellModel.FLAG_CHANGE)) {
setFlag(model.isFlagged());
} else if (propName.equals(MineCellModel.BUTTON_PRESSED)) {
if (model.isMineBlown()) {
setMineBlown(true);
} else {
String labelText = (model.getValue() == 0) ? "" : String.valueOf(model
.getValue());
label.setText(labelText);
}
showCard(LABEL);
}
}
}
public void reset() {
setFlag(false);
setMineBlown(false);
showCard(BUTTON);
label.setText("");
}
}
class MineCellModel {
public static final String FLAG_CHANGE = "Flag Change";
public static final String BUTTON_PRESSED = "Button Pressed";
public static final String MINE_BLOWN = "Mine Blown";
private int row;
private int col;
private int value = 0;
private boolean mined = false;;
private boolean flagged = false;
private SwingPropertyChangeSupport pcSupport = new SwingPropertyChangeSupport(this);
private boolean pressed = false;
private boolean mineBlown = false;
public MineCellModel(boolean mined, int row, int col) {
this.mined = mined;
this.row = row;
this.col = col;
}
public void incrementValue() {
int temp = value + 1;
setValue(temp);
}
public void setValue(int value) {
this.value = value;
}
public int getValue() {
return value;
}
public void setMineBlown(boolean mineBlown) {
this.mineBlown = mineBlown;
PropertyChangeEvent evt = new PropertyChangeEvent(this, MINE_BLOWN, false, true);
pcSupport.firePropertyChange(evt);
}
public boolean isMineBlown() {
return mineBlown;
}
public void setMined(boolean mined) {
this.mined = mined;
}
public void setFlagged(boolean flagged) {
this.flagged = flagged;
}
public int getRow() {
return row;
}
public int getCol() {
return col;
}
public boolean isMined() {
return mined;
}
public boolean isFlagged() {
return flagged;
}
public void pressedAction() {
if (pressed) {
return;
}
pressed = true;
if (mined) {
setMineBlown(true);
}
PropertyChangeEvent evt = new PropertyChangeEvent(this, BUTTON_PRESSED, -1, value);
pcSupport.firePropertyChange(evt);
}
public void upDateButtonFlag() {
boolean oldValue = flagged;
setFlagged(!flagged);
PropertyChangeEvent evt = new PropertyChangeEvent(this, FLAG_CHANGE, oldValue, flagged);
pcSupport.firePropertyChange(evt);
}
public void reset() {
mined = false;
flagged = false;
pressed = false;
mineBlown = false;
value = 0;
}
public void addPropertyChangeListener(PropertyChangeListener listener) {
pcSupport.addPropertyChangeListener(listener);
}
public void removePropertyChangeListener(PropertyChangeListener listener) {
pcSupport.removePropertyChangeListener(listener);
}
}
Edit Regarding Recursion
My code uses recursion, but with a level of indirection, since it is based on a Model-View-Controller type of design pattern, and the recursion is within the notification of listeners. Note that each GUI MineCell object holds its own MineCellModel object, the latter holds the MineCell's state. When a GUI JButton held within the MineCell object is pressed, its ActionListener calls the same class's pressed() method:
button.addActionListener(new ActionListener() {
public void actionPerformed(ActionEvent e) {
pressedAction();
}
});
This method first checks the corresponding MineCellModel to see if it has been "flagged", if a boolean called flagged is true. If so, this means that the user has right-clicked on the button, and it is not active, and so the method returns. Otherwise the MineCellModel's pressedAction() method is called,
public void pressedAction() {
if (model.isFlagged()) {
return;
}
model.pressedAction();
}
and here is where the recursion starts, and it does so through an Observer Design Pattern:
// within MineCellModel
public void pressedAction() {
if (pressed) {
// if the button's already been pressed -- return, do nothing
return;
}
// otherwise make pressed true
pressed = true;
// if we've hit a mine -- blow it!
if (mined) {
setMineBlown(true);
}
// *** Here's the key *** notify all listeners that this button has been pressed
PropertyChangeEvent evt = new PropertyChangeEvent(this, BUTTON_PRESSED, -1, value);
pcSupport.firePropertyChange(evt);
}
The two lines of code on the bottom notify any listeners to this model that its BUTTON_PRESSED state has been changed, and it sends the MineCellModel's value to all listeners. The value int is key as its the number of neighbors that have mines. So what listens to the MineCellModel? Well, one key object is the MineCellGridModel, the model that represents the state of the entire grid. It has a CellModelPropertyChangeListener class that does the actual listening, and within this class is the following code:
private class CellModelPropertyChangeListener implements PropertyChangeListener {
public void propertyChange(PropertyChangeEvent evt) {
// first get the MineCellModel for the cell that triggered this notification
MineCellModel model = (MineCellModel) evt.getSource();
int row = model.getRow();
int col = model.getCol();
// if the event is a button pressed event
if (evt.getPropertyName().equals(MineCellModel.BUTTON_PRESSED)) {
// first check if a mine was hit, and if so, call mineBlown()
if (cellModelGrid[row][col].isMineBlown()) {
mineBlown(); // this method iterates through all cells and blows all mines
} else {
// here we check for a winner
buttonsRemaining--;
if (buttonsRemaining <= 0) {
JOptionPane.showMessageDialog(null, "You've Won!!!", "Congratulations",
JOptionPane.PLAIN_MESSAGE);
}
// here is the key spot -- if cell's value is 0, call the zeroValuePress method
if (cellModelGrid[row][col].getValue() == 0) {
zeroValuePress(row, col);
}
}
}
}
private void mineBlown() {
// ... code to blow all the un-blown mines
}
// this code is called if a button pressed has 0 value -- no mine neighbors
private void zeroValuePress(int row, int col) {
// find the boundaries of the neighbors
int rMin = Math.max(row - 1, 0); // check for the top edge
int cMin = Math.max(col - 1, 0); // check for the left edge
int rMax = Math.min(row + 1, cellModelGrid.length - 1); // check for the bottom edge
int cMax = Math.min(col + 1, cellModelGrid[row].length - 1); // check for right edge
// iterate through the neighbors
for (int row2 = rMin; row2 <= rMax; row2++) {
for (int col2 = cMin; col2 <= cMax; col2++) {
// *** Here's the recursion ***
// call pressedAction on all the neighbors
cellModelGrid[row2][col2].pressedAction();
}
}
}
}
So the key method in the listener above is the zeroValuePress(...) method. It first finds the boundaries of the neighbors around the current mine cell, using Math.min(...) and Math.max(...) to be careful not to go beyond the right, left, or top or bottom boundaries of the grid. It then iterates through the cell neighbors calling pressedAction() on each one of the neighbors MineCellModels held by this grid. As you know from above, the pressedAction() method will check if the cell has already been pressed, and if not, changes its state, which then notifies this same listener, resulting in recursion.

One of the primary functions of this game is to have a recursion to check all the sides when the tile clicked has no bombs surrounding it.
Looks like you are stucked on the part where you need to update the cell with number according to the number of bombs surrounding it.
These are the things for you to take note:
To update the numbers on the cells, there is no need to use recursion. The only part I used recursion is when user clicks on a cell with value == 0(stepped on an empty grid).
Checking all 8 directions can be done easily without writing large number of if-conditions. All you need is a pair of nested for-loop. Just traverse the 3x3 grid like a 2D array (see diagram below for illustration).
In the loop, set conditions to ensure you are within bounds (of the 3x3 matrix) before reading current grid's value (see code below).
To traverse the 3x3 matrix as shown in the diagram, we can use a pair of nested loops:
for(int x=(coordX-1); x<=(coordX+1); x++)
for(int y=(coordY-1); y<=(coordY+1); y++)
if(x!=-1 && y!= -1 && x! = ROWS && y! = COLS && map[x][y] != 'B')
if(map[x][y] == '.')
map[x][y] = '1';
else
map[x][y] += 1;
The if-condition prevents working on array element which is out of bounds.

Related

Gui to visualize recursive backtracking sudoku

I wrote a class a while ago to solve a sudoku game using recursive backtracking - that's working as expected.
Now I want to visualize this algorithm step by step. I basically want to see where the algorithm put which number and when it is backtracking.
I wrote all the necessary function and implemented a basic gui that already calls and displays my sudokuSolver inside my gui (after you start it and press a random key once you want to begin the solving).
Now my problem is that I want to see each step of the algorithm - see more in the SudokuSolver.solve() function.
At the moment I somehow only update my gui once the whole backtracking is finished, although my SudokuSlver.setGui() function is called during the backtracking.
Which is also the reason why my approach to "slow down" the algorithm with "Thread.sleep()" and "TimeUnit" failed.
Github
Code Gui.java
import java.util.ArrayList;
import java.util.concurrent.*;
import javafx.application.Application;
import javafx.event.EventHandler;
import javafx.scene.Scene;
import javafx.scene.input.KeyEvent;
import javafx.scene.shape.*;
import javafx.scene.text.Text;
import javafx.scene.text.TextBoundsType;
import javafx.scene.layout.Pane;
import javafx.stage.Stage;
import javafx.scene.paint.*;
public class Gui extends Application{
static ArrayList<Rectangle> rects = new ArrayList<>();
static ArrayList<Text> texts = new ArrayList<>();
#Override
public void start(Stage stage) {
Pane pane = new Pane();
Scene scene = new Scene(pane, 297, 297);
createBoard();
for (int box = 0; box < rects.size(); box++) {
pane.getChildren().addAll(rects.get(box), texts.get(box));
}
scene.setOnKeyPressed(new EventHandler<KeyEvent>(){
public void handle(final KeyEvent keyEvent){
System.out.println("event triggered");
handleEvent(keyEvent);
}
});
stage.setTitle("SudokuSolver");
stage.setScene(scene);
stage.show();
}
public void handleEvent(KeyEvent key){
System.out.println("event triggered");
callSudokuSolver();
}
public void createBoard(){
for (int x = 0; x < 288; x+=32) {
for (int y = 0; y < 288; y+=32) {
Rectangle r = new Rectangle(x, y, 32, 32);
Text text = createText("0");
text.setX(x);
text.setY(y+32);
r.setFill(Color.WHITE);
r.setStroke(Color.BLACK);
r.setOpacity(0.5);
rects.add(r);
texts.add(text);
}
}
}
public static void setTextOfRect(String s, int pos){
texts.get(pos).setText(s);
}
public static void setColorOfRect(Color col, int pos){
rects.get(pos).setFill(col);
}
private Text createText(String string) {
Text text = new Text(string);
text.setBoundsType(TextBoundsType.VISUAL);
text.setStyle(
"-fx-font-family: \"Times New Roman\";" +
"-fx-font-size: 16px;"
);
return text;
}
private void callSudokuSolver(){
//test
int[][] board =
{{2,0,5,0,0,0,0,0,0},
{3,0,8,6,0,0,9,0,0},
{0,0,0,1,0,0,4,0,0},
{0,0,0,0,5,0,0,1,0},
{0,0,0,0,9,0,0,2,0},
{8,7,0,0,2,0,0,0,0},
{0,0,0,0,8,9,0,0,3},
{0,0,6,0,0,3,0,0,5},
{5,0,4,0,0,0,0,0,1}};
SudokuSolver sudokuSolver = new SudokuSolver();
if(!sudokuSolver.startSolving(board)){
System.out.println("No solution");
}else{
System.out.println("Solved");
}
}
public static void main(String[] args) throws Exception {
launch();
}
}
Code SudokuSolver.java
import javafx.scene.paint.*;
public class SudokuSolver {
private boolean solve(int[][] board, int counter){
int col = counter / board.length;
int row = counter % board.length;
if (col >= board.length){
return true;
}
if (board[row][col] == 0) {
for (int n = 1; n <= board.length; n++) {
if (isValid(n,row,col, board)){
board[row][col] = n;
setGui(false, counter, n);
if (solve(board,counter+1)){
return true;
}
}
board[row][col] = 0;
setGui(true, counter, n);
}
}else{
setGui(false, counter, board[row][col]);
return solve(board, counter + 1);
}
return false;
}
public boolean startSolving(int[][] board){
if(!solve(board, 0)){
return false;
}else{
return true;
}
}
private boolean isValid(int n, int row, int col, int[][] board){
int i;
for (i = 0; i < board.length; i++) {
if(board[row][i] == n){
return false;
}
}
for (i = 0; i < board.length; i++) {
if(board[i][col] == n){
return false;
}
}
//check if block is valid
final int blockRow = 3 * (row / 3);
final int blockCol = 3 * (col / 3);
return isBlockValid(n, board, blockRow, blockRow + 2, blockCol, blockCol + 2);
}
private boolean isBlockValid(int n, int[][] board, int starti, int stopi, int startj, int stopj){
for (int i = starti; i <= stopi; i++) {
for (int j = startj; j <= stopj; j++) {
if (board[i][j] == n) {
return false;
}
}
}
return true;
}
private void printBoard(int[][] board){
System.out.println();
for (int[] row : board){
System.out.print("|");
for (int col : row){
System.out.print(col);
System.out.print("|");
}
System.out.println();
}
System.out.println();
}
private void setGui(boolean wrong, int pos, int number){
String s = Integer.toString(number);
Color color = Color.GREEN;
if(wrong){
color = Color.RED;
}
Gui.setColorOfRect(color, pos);
Gui.setTextOfRect(s, pos);
}
}
https://stackoverflow.com/a/9167420/11162097 solved my problem.
It was necessary to open my sodokusolver in another thread and then run the gui commands with Platform.runLater() (#tevemadar).
new Thread() {
public void run() {
SudokuSolver sudokuSolver = new SudokuSolver();
sudokuSolver.startSolving(board);
}
}.start();
After that I used this to "slow down" my algorithm.
try {
Thread.sleep(10);
} catch (Exception e) {
//TODO: handle exception
}

Grid DFS visualization

Hello guys I am working on a project where I am trying to create a maze generator.
So far I have a gird that is a 2D array of a Cell class and a JPanel that paints the grid to a JFrame and a function which uses Depth first Search to visit each Cell in the grid.
When the Cell has been visited the Cell color changes to black on the grid. My problem is the repaint on the grid is too fast is there anyway I can slow the time or set a timer to repaint after a number of seconds. Here is the code below
import java.util.Arrays;
import java.util.Stack;
import javax.swing.JFrame;
import javax.swing.JPanel;
import javax.swing.Timer;
import java.awt.Graphics;
import java.awt.event.ActionEvent;
import java.awt.event.ActionListener;
import java.security.SecureRandom;
public class Maze extends JPanel implements ActionListener {
private Cell [][] maze;
private int dims;
private Stack<Cell> S = new Stack<Cell>();
private SecureRandom num = new SecureRandom();
Timer t;
public Maze(int din)
{
dims = din;
maze = new Cell[dims][dims];
}
public void generator()
{
for(int i = 0; i < maze.length; i++)
{
for (int j = 0;j < maze[0].length; j++)
{
maze[i][j] = new Cell(i,j);
}
}
}
public boolean checkAll()
{
for(int i = 0; i < maze.length; i++)
{
for (int j = 0;j < maze[0].length; j++)
{
if(!maze[i][j].visited)
return false;
}
}
return true;
}
public void adjlist()
{
for(int i = 0; i < maze.length; i++)
{
for (int j = 0;j < maze[0].length; j++)
{
if(i+1 >= 0 && i+1 < dims)
{
maze[i][j].neighbor.add(maze[i+1][j]);
}
if(i-1 >= 0 && i-1 < dims)
{
maze[i][j].neighbor.add(maze[i-1][j]);
}
if(j-1 >= 0 && j-1 < dims)
{
maze[i][j].neighbor.add(maze[i][j-1]);
}
if(j+1 >= 0 && j+1 < dims)
{
maze[i][j].neighbor.add(maze[i][j+1]);
}
}
}
}
public void DFS(Cell x)
{
if (!checkAll() && !maze[x.row][x.column].visited)
{
S.push(x);
System.out.println(Arrays.toString(S.toArray()));
maze[x.row][x.column].visited = true;
int randnum = num.nextInt(maze[x.row][x.column].neighbor.size());
Cell temp1 = maze[x.row][x.column].neighbor.get(randnum);
if (!maze[temp1.row][temp1.column].visited)
{
DFS(maze[temp1.row][temp1.column]);
}
else if (maze[x.row][x.column].neighbor.isEmpty())
{
S.pop();
maze[S.peek().row][S.peek().column].visited = false;
DFS(S.pop());
}
else
{
if(S.size()-1 == 0)
return;
Cell temp = null;
for (Cell c : maze[x.row][x.column].neighbor)
{
if (!maze[c.row][c.column].visited)
{
temp = c;
DFS(temp);
}
}
if (temp == null) {
S.pop();
maze[S.peek().row][S.peek().column].visited = false;
DFS(S.pop());
}
}
}
}
public void paint(Graphics g)
{
super.paint(g);
for (int row = 0; row < maze.length; row++)
{
for (int col = 0; col < maze[0].length; col++)
{
g.drawRect(35*row, 35 * col , 35, 35);
if(maze[row][col].visited)
{
//t.start();
g.fillRect(35*row, 35 * col , 35, 35);
//t.setDelay(5000);
}
}
}
repaint();
try {
Thread.sleep(5000);
} catch (InterruptedException e) {
// TODO Auto-generated catch block
e.printStackTrace();
}
}
public static void main(String[] args)
{
Maze p = new Maze(10);
p.generator();
p.adjlist();
System.out.println("------------------------");
JFrame f = new JFrame();
f.setTitle("Maze");
f.add(p);
f.setVisible(true);
f.setSize(700, 700);
f.setLocationRelativeTo(null);
f.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
p.DFS(new Cell(1,5));
}
#Override
public void actionPerformed(ActionEvent e) {}
}
The cell class
import java.util.ArrayList;
public class Cell{
public int row, column;
boolean visited;
ArrayList<Cell> neighbor;
public Cell(int i, int j)
{
row = i;
column = j;
visited = false;
neighbor = new ArrayList<Cell>();
}
public int getRow()
{
return this.row;
}
public int getCol()
{
return this.column;
}
public String toString()
{
return this.row + " " + this.column;
}
}
The following code demonstrates the use of SwingWorker to demonstrate performing long tasks (in your case dfs search) which update the gui.
Specific dfs information was removed because they are not relevant:
import java.awt.Dimension;
import java.awt.Graphics;
import java.util.Random;
import javax.swing.JFrame;
import javax.swing.JPanel;
import javax.swing.SwingWorker;
public class Maze extends JPanel {
private final Cell [][] maze;
private final int dims;
private static final int SIZE = 35;
public Maze(int dim) {
setPreferredSize(new Dimension( dim*SIZE,dim*SIZE));
dims = dim;
maze = new Cell[dims][dims];
}
public void generator()
{
for(int i = 0; i < maze.length; i++)
{
for (int j = 0;j < maze[0].length; j++)
{
maze[i][j] = new Cell(i,j);
//set some arbitrary initial date
if(i%2 ==0 && j%2 ==0) {
maze[i][j].setVisited(true);
}
}
}
}
public void DFS()
{
new DFSTask().execute();
}
#Override
public void paintComponent(Graphics g) //override paintComponent not paint
{
super.paintComponent(g);
for (int row = 0; row < maze.length; row++)
{
for (int col = 0; col < maze[0].length; col++)
{
g.drawRect(SIZE*row, SIZE * col , SIZE, SIZE);
if(maze[row][col].visited)
{
g.fillRect(SIZE*row, SIZE * col , SIZE, SIZE);
}
}
}
}
public static void main(String[] args)
{
Maze p = new Maze(10);
p.generator();
JFrame f = new JFrame();
f.setLocationRelativeTo(null);
f.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
f.add(p);
f.pack();
f.setVisible(true);
p.DFS();
}
//use swing worker perform long task
class DFSTask extends SwingWorker<Void,Void> {
private static final long DELAY = 1000;
private final Random rand = new Random();
#Override
public Void doInBackground() {
dfs();
return null;
}
#Override
public void done() { }
void dfs() { //simulates long process that repeatedly updates gui
while (true){ //endless loop, just for demonstration
//update info
int row = rand.nextInt(dims);
int col = rand.nextInt(dims);
maze[row][col].setVisited(! maze[row][col].isVisited());
repaint(); //update jpanel
try {
Thread.sleep(DELAY); //simulate long process
} catch (InterruptedException ex) { ex.printStackTrace();}
}
}
}
}
class Cell{
private final int row, column;
boolean visited;
public Cell(int i, int j)
{
row = i;
column = j;
visited = false;
}
int getRow() { return row; }
int getColumn() {return column; }
boolean isVisited() { return visited; }
void setVisited(boolean visited) { this.visited = visited;}
#Override
public String toString()
{
return row + " " + column;
}
}
For more information about using SwingWorker see doc

Hello I am creating a TicTacToe game for myself to understand Java better

however I am not sure where I am supposed to enter the whoWins() method. Do I enter this method in the actionperformed Method of the buttons or do i need to something different. Please help.
public class TTT extends JFrame implements ActionListener {
private JButton buttons[] = new JButton[9];
private JButton exitButton;
public JLabel title;
public JPanel titlePanel, panel;
private int count = 0;
int symbolCount = 0;
private boolean win = false;
public TTT() {
title = new JLabel("Welcome to my Tic Tac Toe Game!");
titlePanel = new JPanel();
title.setFont(new Font(Font.SERIF, 0, 30));
titlePanel.add(title);
this.add(titlePanel, BorderLayout.NORTH);
panel = new JPanel(new GridLayout(3, 3));
for (int i = 0; i < buttons.length; i++) {
buttons[i] = new JButton();
panel.add(buttons[i]);
buttons[i].setEnabled(true);
buttons[i].addActionListener(this);
}
this.add(panel, BorderLayout.CENTER);
JPanel panel1 = new JPanel(new FlowLayout(FlowLayout.CENTER));
exitButton = new JButton("Quit");
panel1.add(exitButton);
this.add(panel1, BorderLayout.SOUTH);
exitButton.addActionListener(new ActionListener() {
#Override
public void actionPerformed(ActionEvent e) {
System.exit(WIDTH);
}
});
}
public void whoWins() {
//Determines who wins using for the horizontal rows.
if (buttons[0].getText() == buttons[1].getText() && buttons[1].getText() == buttons[2].getText() && buttons[0].getText() != "") {
win = true;
} else if (buttons[3].getText() == buttons[4].getText() && buttons[4].getText() == buttons[5].getText() && buttons[3].getText() != "") {
win = true;
} else if (buttons[6].getText() == buttons[7].getText() && buttons[7].getText() == buttons[8].getText() && buttons[6].getText() != "") {
win = true;
} //Determines the verticles wins
else if (buttons[0].getText() == buttons[3].getText() && buttons[3].getText() == buttons[6].getText() && buttons[0].getText() != "") {
win = true;
} else if (buttons[1].getText() == buttons[4].getText() && buttons[4].getText() == buttons[7].getText() && buttons[1].getText() != "") {
win = true;
} else if (buttons[2].getText() == buttons[5].getText() && buttons[5].getText() == buttons[8].getText() && buttons[2].getText() != "") {
win = true;
}
// Diagnol Wins
else if (buttons[0].getText()==buttons[4].getText()&&buttons[4].getText()==buttons[8].getText()&& buttons[0].getText()!= "") {
win = true;
}else if (buttons[2].getText()==buttons[4].getText()&&buttons[4].getText()==buttons[6].getText()&& buttons[1].getText()!= "") {
win = true;
}else {
win = false;
}
//who won
if (win = true) {
JOptionPane.showMessageDialog(null, "wins");
}else if (count == 9 && win == false) {
JOptionPane.showMessageDialog(null, "Tie game");
}
}
public static void main(String[] args) {
TTT ref1 = new TTT();
ref1.setTitle("Tic Tac Toe");
ref1.setVisible(true);
ref1.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
ref1.setSize(500, 500);
ref1.setLocationRelativeTo(null);
// ref1.whoWins();
}
#Override
public void actionPerformed(ActionEvent e) {
count++;
for (JButton button : buttons) {
if (button == e.getSource()) {
if (symbolCount % 2 == 0) {
button.setText("X");
button.setEnabled(false);
} else {
button.setText("O");
button.setEnabled(false);
}
}
}
if (count >= buttons.length) {
JOptionPane.showMessageDialog(null, "End");
}
symbolCount++;
}
}
If you really want to do this right, then I suggest making some big changes, some M-V-C type changes:
First and foremost, separate out the logic of the game from the game GUI. This would mean that the code that determines who wins should not be in any code that contains GUI type code. This will be your "model"
Next you should never have GUI code implement listener interfaces, so try to get that out of the GUI and possibly have it go into its own class, the "Control" class.
Finally the GUI or "View" class will concern itself with displaying the model's state and getting input from the user and transmitting this input to the control.
For example,...
import java.awt.BorderLayout;
import java.awt.Color;
import java.awt.Component;
import java.awt.GridLayout;
import java.awt.Window;
import java.awt.event.*;
import java.awt.image.BufferedImage;
import java.beans.PropertyChangeEvent;
import java.beans.PropertyChangeListener;
import java.io.IOException;
import java.util.EnumMap;
import java.util.Map;
import javax.imageio.ImageIO;
import javax.swing.*;
import javax.swing.event.SwingPropertyChangeSupport;
public class TicTacToeMain {
private static void createAndShowGui() {
TttView view = null;
try {
view = new TttView();
} catch (IOException e) {
e.printStackTrace();
System.exit(-1);
}
TttModel model = new TttModel();
new TttControl(model, view);
JFrame frame = new JFrame("Tic Tac Toe");
frame.setDefaultCloseOperation(JFrame.DISPOSE_ON_CLOSE);
frame.getContentPane().add(view.getMainPanel());
frame.pack();
frame.setLocationByPlatform(true);
frame.setVisible(true);
}
public static void main(String[] args) {
SwingUtilities.invokeLater(new Runnable() {
public void run() {
createAndShowGui();
}
});
}
}
enum TttPiece {
EMPTY, X, O
}
class TttView {
public static final String IMAGE = "/imgFolder/TicTacToe.png";
private static final int GAP = 5;
private JPanel mainPanel = new JPanel();
private JPanel tttPanel = new JPanel();
private Map<TttPiece, Icon> iconMap = new EnumMap<>(TttPiece.class);
private JLabel[][] grid = new JLabel[TttModel.ROWS][TttModel.COLS];
private TttControl control;
public TttView() throws IOException {
BufferedImage img = ImageIO.read(getClass().getResourceAsStream(IMAGE));
Icon[] imgIcons = splitImg(img);
iconMap.put(TttPiece.X, imgIcons[0]);
iconMap.put(TttPiece.O, imgIcons[1]);
iconMap.put(TttPiece.EMPTY, createEmptyIcon(imgIcons[0]));
tttPanel.setLayout(new GridLayout(grid.length, grid[0].length, GAP, GAP));
tttPanel.setBackground(Color.black);
MyMouseAdapter mouseAdapter = new MyMouseAdapter();
for (int row = 0; row < grid.length; row++) {
for (int col = 0; col < grid[row].length; col++) {
grid[row][col] = new JLabel(iconMap.get(TttPiece.EMPTY));
grid[row][col].setOpaque(true);
grid[row][col].setBackground(Color.LIGHT_GRAY);
grid[row][col].addMouseListener(mouseAdapter);
tttPanel.add(grid[row][col]);
}
}
JPanel btnPanel = new JPanel(new GridLayout(1, 0, 5, 0));
btnPanel.add(new JButton(new ClearAction("Clear", KeyEvent.VK_C)));
btnPanel.add(new JButton(new ExitAction("Exit", KeyEvent.VK_X)));
int blGap = 2;
mainPanel.setLayout(new BorderLayout(blGap, blGap));
mainPanel.setBorder(BorderFactory.createEmptyBorder(blGap, blGap, blGap,
blGap));
mainPanel.add(tttPanel, BorderLayout.CENTER);
mainPanel.add(btnPanel, BorderLayout.SOUTH);
}
public void setControl(TttControl control) {
this.control = control;
}
public JComponent getMainPanel() {
return mainPanel;
}
private Icon createEmptyIcon(Icon icon) {
int width = icon.getIconWidth();
int height = icon.getIconHeight();
BufferedImage img = new BufferedImage(width, height,
BufferedImage.TYPE_INT_ARGB);
return new ImageIcon(img);
}
private Icon[] splitImg(BufferedImage img) {
int w = img.getWidth();
int h = img.getHeight();
int gap = 5;
Icon[] icons = new ImageIcon[2];
icons[0] = new ImageIcon(img.getSubimage(0, 0, w / 2 - gap, h / 2 - gap));
icons[1] = new ImageIcon(img.getSubimage(w / 2 + gap, 0, w / 2 - gap, h
/ 2 - gap));
return icons;
}
private class MyMouseAdapter extends MouseAdapter {
#Override
public void mousePressed(MouseEvent e) {
if (control == null) {
return;
}
for (int row = 0; row < grid.length; row++) {
for (int col = 0; col < grid[row].length; col++) {
if (grid[row][col] == e.getSource()) {
control.gridPress(row, col);
}
}
}
}
}
private class ClearAction extends AbstractAction {
public ClearAction(String name, int mnemonic) {
super(name);
putValue(MNEMONIC_KEY, mnemonic);
}
#Override
public void actionPerformed(ActionEvent evt) {
if (control != null) {
control.clear();
}
}
}
private class ExitAction extends AbstractAction {
public ExitAction(String name, int mnemonic) {
super(name);
putValue(MNEMONIC_KEY, mnemonic);
}
#Override
public void actionPerformed(ActionEvent evt) {
if (control != null) {
control.exit(evt);
}
}
}
public void setGridIcon(int row, int col, TttPiece tttPiece) {
grid[row][col].setIcon(iconMap.get(tttPiece));
}
}
class TttControl {
private TttModel model;
private TttView view;
public TttControl(TttModel model, TttView view) {
this.model = model;
this.view = view;
view.setControl(this);
model.addPropertyChangeListener(new ModelListener());
}
public void exit(ActionEvent evt) {
Window win = SwingUtilities
.getWindowAncestor((Component) evt.getSource());
win.dispose();
}
public void gridPress(int row, int col) {
try {
model.gridPress(row, col);
} catch (TttException e) {
// TODO: notify user
// e.printStackTrace();
}
}
public void clear() {
model.clear();
}
private class ModelListener implements PropertyChangeListener {
#Override
public void propertyChange(PropertyChangeEvent evt) {
if (TttModel.GRID_POSITION.equals(evt.getPropertyName())) {
TttPiece[][] tttGrid = model.getTttGrid();
for (int row = 0; row < tttGrid.length; row++) {
for (int col = 0; col < tttGrid[row].length; col++) {
view.setGridIcon(row, col, tttGrid[row][col]);
}
}
}
}
}
}
class TttModel {
public static final int ROWS = 3;
public static final int COLS = ROWS;
public static final String GRID_POSITION = "grid position";
private SwingPropertyChangeSupport pcSupport = new SwingPropertyChangeSupport(
this);
private TttPiece[][] tttGrid = new TttPiece[ROWS][COLS];
private TttPiece player = TttPiece.X;
private boolean gameOver;
public TttModel() {
clear();
}
public void setGridPosition(int row, int col, TttPiece piece)
throws TttException {
if (gameOver) {
return;
}
if (tttGrid[row][col] == TttPiece.EMPTY) {
tttGrid[row][col] = piece;
checkForWin(row, col, piece);
nextPlayer();
pcSupport.firePropertyChange(GRID_POSITION, null, tttGrid);
} else {
String message = "Invalid setGridPosition for row: %d, col: %d, piece: %s. "
+ "Spot already occupied by piece: %s";
message = String.format(message, row, col, piece, tttGrid[row][col]);
throw new TttException(message);
}
}
public TttPiece[][] getTttGrid() {
return tttGrid;
}
public void gridPress(int row, int col) throws TttException {
setGridPosition(row, col, player);
}
public void nextPlayer() {
player = player == TttPiece.X ? TttPiece.O : TttPiece.X;
}
private void checkForWin(int row, int col, TttPiece piece) {
// TODO finish
}
public void clear() {
for (int row = 0; row < tttGrid.length; row++) {
for (int col = 0; col < tttGrid[row].length; col++) {
tttGrid[row][col] = TttPiece.EMPTY;
}
}
player = TttPiece.X;
pcSupport.firePropertyChange(GRID_POSITION, null, tttGrid);
}
public void addPropertyChangeListener(PropertyChangeListener listener) {
pcSupport.addPropertyChangeListener(listener);
}
public void removePropertyChangeListener(PropertyChangeListener listener) {
pcSupport.removePropertyChangeListener(listener);
}
}
#SuppressWarnings("serial")
class TttException extends Exception {
public TttException() {
super();
}
public TttException(String message) {
super(message);
}
}
Using for my images:
With GUI looking like:
I am also interested in writing a Tic Tac Toe game, so I copied your code, and did a little modification, and it passed test, check following:
package eric.j2se.swing;
import java.awt.BorderLayout;
import java.awt.FlowLayout;
import java.awt.Font;
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.JOptionPane;
import javax.swing.JPanel;
/**
* <p>
* Simple game of Tic Tac Toe.
* </p>
*
* #author eric
* #date Apr 16, 2014 11:03:48 AM
*/
#SuppressWarnings("serial")
public class TicTacToe extends JFrame implements ActionListener {
// 2 players
public static final char playerX = 'X';
public static final char playerO = 'O';
// null player
public static final char playerN = 'N';
// the winer, init to null player
private Character winner = playerN;
// indicate whether game over
private boolean gameOver = false;
// count of button used,
private int count = 0;
private Character buttonPlayers[] = new Character[9];
private JButton buttons[] = new JButton[9];
private JButton exitButton;
public JLabel title;
public JPanel titlePanel, panel;
public TicTacToe() {
// init buttonPlayers
for (int i = 0; i < 9; i++) {
buttonPlayers[i] = playerN;
}
// init title
title = new JLabel("Welcome to Tic Tac Toe!");
titlePanel = new JPanel();
title.setFont(new Font(Font.SERIF, 0, 30));
titlePanel.add(title);
this.add(titlePanel, BorderLayout.NORTH);
// init 9 button
panel = new JPanel(new GridLayout(3, 3));
for (int i = 0; i < buttons.length; i++) {
buttons[i] = new JButton();
panel.add(buttons[i]);
buttons[i].setEnabled(true);
buttons[i].addActionListener(this);
}
// init exit button
this.add(panel, BorderLayout.CENTER);
JPanel panel1 = new JPanel(new FlowLayout(FlowLayout.CENTER));
exitButton = new JButton("Quit");
panel1.add(exitButton);
this.add(panel1, BorderLayout.SOUTH);
exitButton.addActionListener(new ActionListener() {
#Override
public void actionPerformed(ActionEvent e) {
System.exit(WIDTH);
}
});
}
public void whoWins() {
// determine winner - horizontal rows
if (!gameOver) {
for (int i = 0; i < 3; i++) {
if ((buttonPlayers[0 + i * 3] != playerN) && (buttonPlayers[0 + i * 3].equals(buttonPlayers[1 + i * 3]))
&& buttonPlayers[1 + i * 3].equals(buttonPlayers[2 + i * 3])) {
winner = buttonPlayers[0 + i * 3];
gameOver = true;
break;
}
}
}
// determine winner - vertical rows
if (!gameOver) {
for (int i = 0; i < 3; i++) {
if ((buttonPlayers[i + 0 * 3] != playerN) && (buttonPlayers[i + 0 * 3].equals(buttonPlayers[i + 1 * 3]))
&& buttonPlayers[i + 1 * 3].equals(buttonPlayers[i + 2 * 3])) {
winner = buttonPlayers[i + 0 * 3];
gameOver = true;
break;
}
}
}
// determine winner - diagonal rows
if (!gameOver) {
int winButtonIndex = -1;
if ((buttonPlayers[0] != playerN) && (buttonPlayers[0].equals(buttonPlayers[4])) && buttonPlayers[4].equals(buttonPlayers[8])) {
winButtonIndex = 0;
} else if ((buttonPlayers[2] != playerN) && (buttonPlayers[2].equals(buttonPlayers[4])) && buttonPlayers[4].equals(buttonPlayers[6])) {
winButtonIndex = 2;
}
if (winButtonIndex >= 0) {
winner = buttonPlayers[winButtonIndex];
gameOver = true;
}
}
// full
if (count == 9) {
gameOver = true;
}
if (gameOver) {
String tip = "";
switch (winner) {
case playerO:
tip = "Player O win!";
break;
case playerX:
tip = "Player X win!";
break;
default:
tip = "Draw game!";
break;
}
JOptionPane.showMessageDialog(null, tip);
}
}
#Override
public void actionPerformed(ActionEvent e) {
for (int i = 0; i < buttons.length; i++) {
JButton button = buttons[i];
if (button == e.getSource()) {
Character currentPlayer = (count % 2 == 1 ? playerX : playerO);
button.setText(String.valueOf(currentPlayer));
buttonPlayers[i] = currentPlayer;
button.setEnabled(false);
break;
}
}
count++;
whoWins();
}
public static void main(String[] args) {
TicTacToe ref1 = new TicTacToe();
ref1.setTitle("Tic Tac Toe");
ref1.setVisible(true);
ref1.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
ref1.setSize(500, 500);
ref1.setLocationRelativeTo(null);
}
}
about when to call the win check:
check each time you click 1 of the 9 buttons,
about the flag:
I use 2 flag instead of 1 flag to indicate game over & winner, because in TTT game, draw game is very usual, after play several times, you always get draw game ...
a little suggestion to your code:
when compare string, use equals(), not ==,
define const values in variable, not write it in logic, e.g. 'O' 'X',
don't repeat code, try use logic control to make it short & easy to read & easy to maintain,

My way to get X and Y index of buttons inside GridLayout

This is related to How to get X and Y index of element inside GridLayout? post and its answers.
For whatever reason none of them suggested to extend JButton to include its position in the grid and in associated array of buttons.
I have made the following illustration that simply displays button's coordinates when it's clicked.
Extended JButton:
package buttons_array;
import javax.swing.*;
#SuppressWarnings("serial")
public class ButtonWithCoordinates extends JButton {
int coordX;
int coordY;
public ButtonWithCoordinates(String buttonText, int coordX, int coordY) {
super(buttonText);
this.coordX = coordX;
this.coordY = coordY;
}
/**
* #return the coordX
*/
public int getCoordX() {
return coordX;
}
/**
* #return the coordY
*/
public int getCoordY() {
return coordY;
}
}
sample GUI:
package buttons_array;
import java.awt.*;
import java.awt.event.*;
import javax.swing.*;
public class ButtonsArray implements ActionListener {
private ButtonWithCoordinates buttons[][];
private int nRows;
private int nCols;
private JFrame frame;
private JPanel panel;
public ButtonsArray(int x, int y) {
if (x > 0 && y > 0) {
nRows = x;
nCols = y;
buttons = new ButtonWithCoordinates[nRows][nCols];
for (int i=0; i < nRows; ++i) {
for (int j=0; j < nCols; ++j) {
buttons[i][j] = new ButtonWithCoordinates(" ", i, j);
buttons[i][j].addActionListener(this);
}
}
} else {
throw new IllegalArgumentException("Illegal array dimensions!!!");
}
}
#Override
public void actionPerformed(ActionEvent e) {
// TODO Auto-generated method stub
ButtonWithCoordinates button = (ButtonWithCoordinates) e.getSource();
button.setText(button.getCoordX() + ", " + button.getCoordY());
}
public void GUI() {
if (buttons == null) { throw new NullPointerException("Array is not initialized!!!"); }
frame = new JFrame();
panel = new JPanel();
frame.setContentPane(panel);
panel.setLayout(new GridLayout(nRows, nCols));
for (int i=0; i < nRows; ++i) {
for (int j=0; j < nCols; ++j) {
panel.add(buttons[i][j]);
}
}
frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
frame.pack();
frame.setVisible(true);
}
public static void main(String[] args) {
SwingUtilities.invokeLater(new Runnable() {
#Override
public void run() {
new ButtonsArray(3, 5).GUI();
}
});
}
}
Now my questions:
Have I been reinventing the wheel here? I mean, is there a more straightforward way to achieve the same?
Is it in any way inferior to searching through the array each time we need to find the coordinates?
The original version of this example used extension:
GridButton extends JButton
The updated version was predicated on the colloquy seen here. While extension may be appropriate in some contexts, a few alternatives are mentioned here; a client property is particularly convenient. Identifying a button from its grid coordinates is also easy:
private static final int N = 5;
List<JButton> list = new ArrayList<>();
…
private JButton getGridButton(int r, int c) {
int index = r * N + c;
return list.get(index);
}

JTextField that has inner fields or preformated format, something like the ip field in windows

I want to create a text field that will be for dates and will have dd.mm.YYYY format. Now what I want the user to type only the numbers, not the dots to. So the field would be like:
_ _. _ _ . _ _ _ _
So when the user wants to type the date: 15.05.2010 for example, he will only type the numbers in the sequence 15052010.
Also I would like, when he presses on left or right arrow, the cursor to go from one field (not JTextField, but field in the JTextField) to the next. So lets say I have JTextField with this text in it: 15.05.2010 If the user is on the beginning and he presses the right arrow, the cursor should go to the .05 field.
I hope you understand me because right now I don't have any idea how to make this, or at least how to look for it on google.
Well, here are 4 classes that solve your problem.
In my case its version control but IP address has the same structure and its easy to modify it.
package com.demo.textfield.version;
import javax.swing.text.Document;
/**
* create documents for text fields
*/
public class DocumentsFactory {
private DocumentsFactory() {}
public static Document createIntDocument() {
return createIntDocument(Integer.MAX_VALUE, Integer.MAX_VALUE);
}
public static Document createIntDocument(int maxValue) {
return createIntDocument(maxValue, Integer.MAX_VALUE);
}
public static Document createIntDocument(int maxValue, int maxLength) {
IntDocument intDocument = new IntDocument();
intDocument.setMaxVal(maxValue);
intDocument.setMaxLength(maxLength);
return intDocument;
}
}
in the followed class we define view:
package com.demo.textfield.version;
import java.awt.Component;
import java.awt.GridBagConstraints;
import java.awt.GridBagLayout;
import java.awt.Insets;
import javax.swing.JPanel;
public class GridbagPanel extends JPanel {
private static final long serialVersionUID = 1L;
public static final Insets NO_INSETS = new Insets(0, 0, 0, 0);
public GridBagConstraints constraints;
private GridBagLayout layout;
public GridbagPanel() {
layout = new GridBagLayout();
constraints = new GridBagConstraints();
constraints.fill = GridBagConstraints.NONE;
constraints.anchor = GridBagConstraints.WEST;
constraints.insets = NO_INSETS;
setLayout(layout);
}
public void setHorizontalFill() {
constraints.fill = GridBagConstraints.HORIZONTAL;
}
public void setNoneFill() {
constraints.fill = GridBagConstraints.NONE;
}
public void add(Component component, int x, int y, int width, int
height, int weightX, int weightY) {
GridBagLayout gbl = (GridBagLayout) getLayout();
gbl.setConstraints(component, constraints);
add(component);
}
public void add(Component component, int x, int y, int width, int height) {
add(component, x, y, width, height, 0, 0);
}
public void setBothFill() {
constraints.fill = GridBagConstraints.BOTH;
}
public void setInsets(Insets insets) {
constraints.insets = insets;
}
}
We use a plain document that contains our main logic (your changes should be here):
package com.demo.textfield.version;
import javax.swing.text.AttributeSet;
import javax.swing.text.BadLocationException;
import javax.swing.text.PlainDocument;
/**
* a class for positive integers
*/
public class IntDocument extends PlainDocument {
/**
*
*/
private static final long serialVersionUID = 1L;
public static final String NUMERIC = "0123456789";
private int maxVal = -1;
private int maxLength = -1;
public IntDocument() {
this.maxVal = -1;
maxVal = Integer.MAX_VALUE;
maxLength = Integer.MAX_VALUE;
}
public void setMaxLength(int maxLength) {
if (maxLength < 0)
throw new IllegalArgumentException("maxLength<0");
this.maxLength = maxLength;
}
public void setMaxVal(int maxVal) {
this.maxVal = maxVal;
}
public void insertString
(int offset, String str, AttributeSet attr)
throws BadLocationException {
if (str == null)
return;
if (str.startsWith(" ") && offset == 0) {
beep();
str = "";
}
if (!isValidForAcceptedCharsPolicy(str))
return;
if (validateLength(offset, str) == false)
return;
if (!isValidForMaxVal(offset, str))
return;
super.insertString(offset, str, attr);
}
public boolean isValidForAcceptedCharsPolicy(String str) {
if (str.equals("")) {
beep();
return false;
}
for (int i = 0; i < str.length(); i++) {
if (NUMERIC.indexOf(String.valueOf(str.charAt(i))) == -1) {
beep();
return false;
}
}
return true;
}
public boolean isValidForMaxVal(int offset, String toAdd) {
String str_temp;
//String str_text = "";
String str1 = "";
String str2 = "";
try {
str1 = getText(0, offset);
str2 = getText(offset, getLength() - offset);
} catch (Exception e) {
e.printStackTrace();
}
int i_value;
str_temp = str1 + toAdd + str2;
//str_temp = str_temp.trim();
i_value = Integer.parseInt(str_temp);
if (i_value > maxVal) {
beep();
return false;
} else
return true;
}
private boolean validateLength(int offset, String toAdd) {
String str_temp;
//String str_text = "";
String str1 = "";
String str2 = "";
try {
str1 = getText(0, offset);
str2 = getText(offset, getLength() - offset);
} catch (Exception e) {
e.printStackTrace();
}
str_temp = str1 + toAdd + str2;
if (maxLength < str_temp.length()) {
beep();
return false;
} else
return true;
}
private void beep() {
//java.awt.Toolkit.getDefaultToolkit().beep();
}
}
And this is last one with main method that implements all above posted code and you get pretty good view. In my case I used list of 4 text fields separated by dot. You can jump from one "window" to another by using arrows or tab or dot or if your number length reached 4. It will work with implementation of FocusAdapter class:
package com.demo.textfield.version;
import java.awt.Color;
import java.awt.Dimension;
import java.awt.FlowLayout;
import java.awt.event.FocusAdapter;
import java.awt.event.FocusEvent;
import java.awt.event.FocusListener;
import java.awt.event.KeyAdapter;
import java.awt.event.KeyEvent;
import java.awt.event.KeyListener;
import java.util.ArrayList;
import java.util.Arrays;
import java.util.Collections;
import java.util.Enumeration;
import java.util.List;
import javax.swing.BorderFactory;
import javax.swing.FocusManager;
import javax.swing.JFrame;
import javax.swing.JLabel;
import javax.swing.JTextField;
import javax.swing.UIManager;
import javax.swing.border.Border;
import javax.swing.event.DocumentEvent;
import javax.swing.event.DocumentListener;
import javax.swing.text.BadLocationException;
import javax.swing.text.Document;
/**
* diplays an version text field
*/
![enter image description here][1]public class VersionTextField extends GridbagPanel {
private static final long serialVersionUID = 1L;
/**
* a text field for each byte
*/
private JTextField[] textFields;
/**
* dots between text fields
*/
private JLabel[] dotsLabels;
/**
* used to calculate enable/disable color; never shown
*/
private static JTextField sampleTextField = new JTextField();
/**
* listen to changes in the byte fields
*/
private MyDocumentListener documentListener;
/**
* list of key listeners
*/
private List<KeyListener> keyListenersList;
/**
* List of Focus Adapter that select all data in JTextFiled during action
* */
private List<FocusAdapter> focusAdapterList;
/**
* list of key listeners
*/
private List<FocusListener> focusListenersList;
private int maxHeight = 0;
public VersionTextField() {
this(4);
}
/**
* #param byteCount
* number of bytes to display
*/
private VersionTextField(int byteCount) {
textFields = new JTextField[byteCount];
for (int i = 0; i < textFields.length; i++) {
textFields[i] = new JTextField(4);
}
//layout
//constraints.insets = new Insets(0, 0, 0, 0);
List<JLabel> dotsLabelsList = new ArrayList<JLabel>();
for (int i = 0; i < textFields.length; i++) {
JTextField textField = textFields[i];
textField.setHorizontalAlignment(JTextField.CENTER);
Document document = DocumentsFactory.createIntDocument(9999);
textField.setDocument(document);
if (i < textFields.length-1) {
add(textField, i * 2, 0, 1, 1);
if (textField.getPreferredSize().height > maxHeight)
maxHeight = textField.getPreferredSize().height;
JLabel label = new JLabel(".");
add(label, (i * 2) + 1, 0, 1, 1);
if (label.getPreferredSize().height > maxHeight)
maxHeight = label.getPreferredSize().height;
dotsLabelsList.add(label);
} else
add(textField, i * 2, 0, 1, 1);
}
//dotsLabels = new JLabel[dotsLabelsList.size()];
dotsLabels = new JLabel[dotsLabelsList.size()];
dotsLabels = dotsLabelsList.toArray(dotsLabels);
for (int i = 0; i < textFields.length; i++) {
JTextField textField = textFields[i];
textField.setBorder(BorderFactory.createEmptyBorder());
}
//init
Color backgroundColor = UIManager.getColor("TextField.background");
setBackground(backgroundColor);
Border border = UIManager.getBorder("TextField.border");
setBorder(border);
//register listeners
for (int i = 1; i < textFields.length; i++) {
JTextField field = textFields[i];
field.addKeyListener(new BackKeyAdapter());
}
documentListener = new MyDocumentListener();
for (int i = 0; i < textFields.length - 1; i++) {
JTextField field = textFields[i];
field.getDocument().addDocumentListener(documentListener);
field.addKeyListener(new ForwardKeyAdapter());
}
for (int i = 0; i < textFields.length; i++) {
JTextField textField = textFields[i];
textField.addKeyListener(new MyKeyListener());
}
for (int i = 0; i < textFields.length; i++) {
JTextField textField = textFields[i];
textField.addFocusListener(new MyFocusAdapter());
}
for (int i = 0; i < textFields.length; i++) {
JTextField textField = textFields[i];
textField.addFocusListener(new MyFocusAdapter());
}
keyListenersList = new ArrayList<KeyListener>();
focusListenersList = new ArrayList<FocusListener>();
focusAdapterList = new ArrayList<FocusAdapter>();
}
public synchronized void addKeyListener(KeyListener l) {
super.addKeyListener(l);
keyListenersList.add(l);
}
public synchronized void addFocusListener(FocusListener l) {
super.addFocusListener(l);
if (focusListenersList != null)
focusListenersList.add(l);
}
public synchronized void removeKeyListener(KeyListener l) {
super.removeKeyListener(l);
if (focusListenersList != null)
keyListenersList.remove(l);
}
public synchronized void removeFocusListener(FocusListener l) {
super.removeFocusListener(l);
keyListenersList.remove(l);
}
public void setEnabled(boolean b) {
super.setEnabled(b);
sampleTextField.setEnabled(b);
for (int i = 0; i < textFields.length; i++) {
JTextField textField = textFields[i];
textField.setEnabled(b);
}
for (int i = 0; i < dotsLabels.length; i++) {
JLabel dotsLabel = dotsLabels[i];
dotsLabel.setEnabled(b);
}
setBackground(sampleTextField.getBackground());
setForeground(sampleTextField.getForeground());
setBorder(sampleTextField.getBorder());
}
public void requestFocus() {
super.requestFocus();
textFields[0].requestFocus();
}
public void setEditable(boolean b) {
sampleTextField.setEditable(b);
setBackground(sampleTextField.getBackground());
setForeground(sampleTextField.getForeground());
setBorder(sampleTextField.getBorder());
for (int i = 0; i < textFields.length; i++) {
JTextField textField = textFields[i];
textField.setEditable(b);
}
for (int i = 0; i < dotsLabels.length; i++) {
JLabel dotsLabel = dotsLabels[i];
dotsLabel.setForeground(sampleTextField.getForeground());
}
}
public boolean isFieldEmpty() {
for (int i = 0; i < textFields.length; i++) {
JTextField textField = textFields[i];
String sCell = textField.getText().trim();
if (!(sCell.equals("")))
return false;
}
return true;
}
public Dimension getPreferredSize() {
if (super.getPreferredSize().height > maxHeight)
maxHeight = super.getPreferredSize().height;
return new Dimension(super.getPreferredSize().width, maxHeight);
}
/**
* clears current text in text fiekd
*/
private void reset() {
for (int i = 0; i < textFields.length; i++) {
JTextField textField = textFields[i];
textField.getDocument().removeDocumentListener(documentListener);
textField.setText("");
textField.getDocument().addDocumentListener(documentListener);
}
}
public static void main(String[] args) {
JFrame frame = new JFrame("test");
VersionTextField ipTextField = new VersionTextField();
ipTextField.setText("9.1.23.1479");
frame.getContentPane().setLayout(new FlowLayout());
frame.getContentPane().add(ipTextField);
frame.pack();
frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
frame.setVisible(true);
}
public void setText(String version) {
if (version == null || "".equals(version) || "null".equals(version))
reset();
else {
setVer(version.split("[.]"));
}
}
private void setVer(String[] ver) {
if (ver == null) {
reset();
return;
}
Enumeration<String> enumeration = Collections.enumeration(Arrays.asList(ver));
for (int i = 0; i < textFields.length; i++) {
JTextField textField = textFields[i];
String s = (String) enumeration.nextElement();
textField.getDocument().removeDocumentListener(documentListener);
textField.setText(s);
textField.getDocument().addDocumentListener(documentListener);
}
}
public void setToolTipText(String toolTipText) {
for (int i = 0; i < textFields.length; i++) {
JTextField textField = textFields[i];
textField.setToolTipText(toolTipText);
}
}
private class MyDocumentListener implements DocumentListener {
#Override
public void insertUpdate(DocumentEvent e) {
Document document = e.getDocument();
try {
JTextField textField = (JTextField) FocusManager.getCurrentManager().getFocusOwner();
String s = document.getText(0, document.getLength());
if (s.length() == 4){ // && textField.getCaretPosition() == 2) {
textField.transferFocus();
}
} catch (BadLocationException e1) {
e1.printStackTrace();
return;
}
}
public void removeUpdate(DocumentEvent e) {
}
#Override
public void changedUpdate(DocumentEvent e) {
// Document document = e.getDocument();
// try {
// Component component = FocusManager.getCurrentManager().getFocusOwner();
// String s = document.getText(0, document.getLength());
//
// // get selected integer
// int valueInt = Integer.parseInt(s);
//
// if (valueInt > 25) {
// component.transferFocus();
// }
//
// } catch (BadLocationException e1) {
// e1.printStackTrace();
// return;
// }
}
}
private class BackKeyAdapter extends KeyAdapter {
public void keyPressed(KeyEvent e) {
JTextField textField = (JTextField) e.getComponent();
if (textField.getCaretPosition() == 0
&& KeyEvent.VK_LEFT == e.getKeyCode()
&& e.getModifiers() == 0)
textField.transferFocusBackward();
if (textField.getCaretPosition() == 0
&& KeyEvent.VK_BACK_SPACE == e.getKeyCode()
&& e.getModifiers() == 0) {
textField.transferFocusBackward();
}
}
}
private class ForwardKeyAdapter extends KeyAdapter {
public void keyPressed(KeyEvent e) {
JTextField textField = (JTextField) e.getComponent();
if (KeyEvent.VK_RIGHT == e.getKeyCode() && e.getModifiers() == 0) {
int length = textField.getText().length();
int caretPosition = textField.getCaretPosition();
if (caretPosition == length) {
textField.transferFocus();
e.consume();
}
}
if (e.getKeyChar() == '.' &&
textField.getText().trim().length() != 0) {
textField.setText(textField.getText().trim());
textField.transferFocus();
e.consume();
}
}
}
/**
* #return current text in ip text field
*/
public String getText() {
StringBuffer buffer = new StringBuffer();
String ipResult;
for (int i = 0; i < textFields.length; i++) {
JTextField textField = textFields[i];
if(textField.getText().trim().equals("")){
return "";
}
buffer.append(Integer.parseInt(textField.getText()));
if (i < textFields.length - 1){
buffer.append('.');
}
}
ipResult = buffer.toString();
return ipResult;
}
/**
* general purpose key listener
*/
private class MyKeyListener implements KeyListener {
public void keyPressed(KeyEvent e) {
for (int i = 0; i < keyListenersList.size(); i++) {
KeyListener keyListener = keyListenersList.get(i);
keyListener.keyPressed(new KeyEvent(VersionTextField.this,
e.getID(), e.getWhen(), e.getModifiers(), e
.getKeyCode(), e.getKeyChar(), e
.getKeyLocation()));
}
}
public void keyReleased(KeyEvent e) {
for (int i = 0; i < keyListenersList.size(); i++) {
KeyListener keyListener = keyListenersList.get(i);
keyListener.keyReleased(new KeyEvent(VersionTextField.this, e
.getID(), e.getWhen(), e.getModifiers(),
e.getKeyCode(), e.getKeyChar(), e.getKeyLocation()));
}
}
public void keyTyped(KeyEvent e) {
for (int i = 0; i < keyListenersList.size(); i++) {
KeyListener keyListener = keyListenersList.get(i);
keyListener.keyTyped(new KeyEvent(VersionTextField.this, e.getID(),
e.getWhen(), e.getModifiers(), e.getKeyCode(), e
.getKeyChar(), e.getKeyLocation()));
}
}
}
private class MyFocusAdapter extends FocusAdapter {
public void focusGained(FocusEvent e) {
for (int i = 0; i < focusListenersList.size(); i++) {
FocusListener focusListener = focusListenersList.get(i);
focusListener.focusGained(new FocusEvent(
VersionTextField.this,
e.getID(),
e.isTemporary(),
e.getOppositeComponent()
));
}
if(e.getComponent() instanceof javax.swing.JTextField){
highlightText((JTextField)e.getSource());
}
}
public void focusLost(FocusEvent e) {
for (int i = 0; i < focusListenersList.size(); i++) {
FocusListener focusListener = focusListenersList.get(i);
focusListener.focusLost(new FocusEvent(
VersionTextField.this,
e.getID(),
e.isTemporary(),
e.getOppositeComponent()
));
}
}
public void highlightText(javax.swing.JTextField ctr){
//ctr.setSelectionColor(Color.BLUE);
//ctr.setSelectedTextColor(Color.WHITE);
ctr.setSelectionStart(0);
ctr.setSelectionEnd(ctr.getText().length());
System.out.println(ctr.getText());
}
}
}
here a view what we got:
here you go
JFormattedTextField

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