Crafting an Interactive Memory Game in Java
Explore our step-by-step guide on how to build a captivating memory game in Java with our comprehensive guide. This hands-on project will not only help your Java assignment but also provide you with valuable skills in Java Swing GUI development. Create an engaging game to challenge your friends and elevate your programming expertise, making it a fun and educational experience for programmers of all levels. Join us on this exciting journey to master Java game development!
Block 1 - Import Statements
```java
import javax.swing.*;
import java.awt.*;
import java.awt.event.ActionEvent;
import java.awt.event.ActionListener;
import java.util.ArrayList;
import java.util.Collections;
import java.util.HashMap;
import java.util.Map;
```
This block includes necessary import statements for Swing GUI components and event handling.
Block 2 - MemoryGame Class Definition
```java
public class MemoryGame {
// Class members and constructor
}
```
This block defines the `MemoryGame` class, which contains the game logic.
Block 3 - Instance Variables
```java
private JFrame frame;
private JButton[][] buttons = new JButton[5][4];
private ImageIcon[][] images = new ImageIcon[5][4];
private ImageIcon empty = new ImageIcon("images\\empty.png");
private int score = 0;
private int clickCount = 0;
private JButton firstButton;
private JButton secondButton;
private JLabel scoreLabel;
private JLabel timeLabel;
private int time = 0;
private int pairsFound = 0;
private Timer gameTime;
```
These are instance variables of the `MemoryGame` class. They include the frame, buttons, images, score, timers, and other game-related data.
Block 4 - MemoryGame Constructor
```java
public MemoryGame() {
frame = new JFrame("Memory Game");
frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
frame.setSize(600, 500);
frame.setLayout(new BorderLayout());
empty = new ImageIcon(empty.getImage().getScaledInstance(150, 90, Image.SCALE_DEFAULT));
JPanel gridPanel = new JPanel(new GridLayout(5, 4));
scoreLabel = new JLabel("Score: 0");
timeLabel = new JLabel("Time: 0");
JPanel scorePanel = new JPanel(new BorderLayout());
scorePanel.add(scoreLabel, BorderLayout.WEST);
scorePanel add(timeLabel, BorderLayout.EAST);
frame.add(scorePanel, BorderLayout.NORTH);
frame.add(gridPanel, BorderLayout.CENTER);
ArrayList imageList = new ArrayList<>();
Map imageMap = new HashMap<>();
for(int i=1; i<=7; i++) {
String imagePath = "images\\" + i + ".png";
ImageIcon imageIcon;
if (!imageMap.containsKey(imagePath)) {
imageIcon = new ImageIcon(imagePath);
imageIcon = new ImageIcon(imageIcon.getImage().getScaledInstance(150, 90, Image.SCALE_DEFAULT));
imageMap.put(imagePath, imageIcon);
} else {
imageIcon = imageMap.get(imagePath);
}
imageList.add(imageIcon);
imageList.add(imageIcon);
}
for(int i=1; i<=3; i++) {
String imagePath = "images\\" + i + ".png";
ImageIcon imageIcon;
if (!imageMap.containsKey(imagePath)) {
imageIcon = new ImageIcon(imagePath);
imageIcon = new ImageIcon(imageIcon.getImage().getScaledInstance(264, 158, Image.SCALE_DEFAULT));
imageMap.put(imagePath, imageIcon);
} else {
imageIcon = imageMap.get(imagePath);
}
imageList.add(imageIcon);
imageList.add(imageIcon);
}
Collections.shuffle(imageList);
int index = 0;
for(int i=0; i<5; i++) {
for(int j=0; j<4; j++) {
buttons[i][j] = new JButton();
buttons[i][j].setIcon(imageList.get(index));
images[i][j] = imageList.get(index);
buttons[i][j].setActionCommand(String.valueOf(index));
buttons[i][j].addActionListener(new ButtonClickListener());
gridPanel.add(buttons[i][j]);
index++;
}
}
Timer hideImageTimer = new Timer(10000, e -> {
for(int i=0; i<5; i++) {
for(int j=0; j<4; j++) {
buttons[i][j].setIcon(empty);
buttons[i][j].setEnabled(true);
}
gameTime.start();
}
});
hideImageTimer.setRepeats(false);
hideImageTimer.start();
gameTime = new Timer(1000, new ActionListener() {
@Override
public void actionPerformed(ActionEvent e) {
time++;
timeLabel.setText("Time: " + time);
}
});
frame.setVisible(true);
}
```
This is the constructor for the `MemoryGame` class. It sets up the game interface, initializes variables, and creates the game grid.
Block 5 - Frame Setup
```java
frame = new JFrame("Memory Game");
frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
frame.setSize(600, 500);
frame.setLayout(new BorderLayout());
```
This block creates and configures the main game frame.
Block 6 - Image Scaling
```java
empty = new ImageIcon(empty.getImage().getScaledInstance(150, 90, Image.SCALE_DEFAULT));
```
It scales the empty image to a specific size.
Block 7 - Panel Setup
```java
JPanel gridPanel = new JPanel(new GridLayout(5, 4));
scoreLabel = new JLabel("Score: 0");
timeLabel = new JLabel("Time: 0");
JPanel scorePanel = new JPanel(new BorderLayout());
scorePanel.add(scoreLabel, BorderLayout.WEST);
scorePanel.add(timeLabel, BorderLayout.EAST);
frame.add(scorePanel, BorderLayout.NORTH);
frame.add(gridPanel, BorderLayout.CENTER);
```
This block creates and configures panels to hold the game grid and score/time labels.
Block 8 - Image Loading and Shuffling
```java
// Image loading and shuffling code
ArrayList imageList = new ArrayList<>();
Map imageMap = new HashMap<>();
for (int i = 1; i <= 7; i++) {
String imagePath = "images\\" + i + ".png";
ImageIcon imageIcon;
if (!imageMap.containsKey(imagePath)) {
imageIcon = new ImageIcon(imagePath);
imageIcon = new ImageIcon(imageIcon.getImage().getScaledInstance(150, 90, Image.SCALE_DEFAULT));
imageMap.put(imagePath, imageIcon);
} else {
imageIcon = imageMap.get(imagePath);
}
imageList.add(imageIcon);
imageList.add(imageIcon);
}
for (int i = 1; i <= 3; i++) {
String imagePath = "images\\" + i + ".png";
ImageIcon imageIcon;
if (!imageMap.containsKey(imagePath)) {
imageIcon = new ImageIcon(imagePath);
imageIcon = new ImageIcon(imageIcon.getImage().getScaledInstance(264, 158, Image.SCALE_DEFAULT));
imageMap.put(imagePath, imageIcon);
} else {
imageIcon = imageMap.get(imagePath);
}
imageList.add(imageIcon);
imageList.add(imageIcon);
}
Collections.shuffle(imageList);
```
This section loads and shuffles the game's image pairs.
Block 9 - Grid Initialization
```java
int index = 0;
for (int i = 0; i < 5; i++) {
for (int j = 0; j < 4; j++) {
buttons[i][j] = new JButton();
buttons[i][j].setIcon(imageList.get(index));
images[i][j] = imageList.get(index);
buttons[i][j].setActionCommand(String.valueOf(index));
buttons[i][j].addActionListener(new ButtonClickListener());
gridPanel.add(buttons[i][j]);
index++;
}
}
```
This block initializes the game grid by adding buttons and assigning images to them.
Block 10 - Timer for Hiding Images
```java
Timer hideImageTimer = new Timer(10000, e -> {
for (int i = 0; i < 5; i++) {
for (int j = 0; j < 4; j++) {
buttons[i][j].setIcon(empty);
buttons[i][j].setEnabled(true);
}
gameTime.start();
}
});
hideImageTimer.setRepeats(false);
hideImageTimer.start();
```
A timer is set up to hide the images after a certain period.
Block 11 - Timer for Game Time
```java
gameTime = new Timer(1000, new ActionListener() {
@Override
public void actionPerformed(ActionEvent e) {
time++;
timeLabel.setText("Time: " + time);
}
});
```
This code sets up a timer to keep track of the game's elapsed time.
Block 12 - Frame Visibility
```java
frame.setVisible(true);
}
```
This line makes the game frame visible to the player.
Block 13 - ButtonClickListener Inner Class
```java
// ButtonClickListener Inner Class
class ButtonClickListener implements ActionListener {
public void actionPerformed(ActionEvent e) {
JButton clickedButton = (JButton) e.getSource();
int clickedIndex = Integer.parseInt(clickedButton.getActionCommand());
clickedButton.setIcon(images[clickedIndex / 4][clickedIndex % 4]);
clickedButton.setEnabled(false);
if (clickCount == 0) {
firstButton = clickedButton;
clickCount++;
} else {
secondButton = clickedButton;
if (firstButton.getIcon().equals(secondButton.getIcon())) {
pairsFound++;
score++;
if (pairsFound == 10) {
gameTime.stop();
JOptionPane.showMessageDialog(frame, "You won the game! Time: " + time + " seconds");
System.exit(0);
}
} else {
score--;
if (score == -10) {
gameTime.stop();
JOptionPane.showMessageDialog(frame, "Game Over! Score: " + score);
System.exit(0);
}
Timer timer = new Timer(1000, e1 -> {
firstButton.setIcon(empty);
firstButton.setEnabled(true);
secondButton.setIcon(empty);
secondButton.setEnabled(true);
});
timer.setRepeats(false);
timer.start();
}
clickCount = 0;
}
scoreLabel.setText("Score: " + score);
}
}
```
This inner class handles button click events and implements the game logic.
Block 14 - actionPerformed Method
```java
public void actionPerformed(ActionEvent e) {
JButton clickedButton = (JButton) e.getSource();
int clickedIndex = Integer.parseInt(clickedButton.getActionCommand());
clickedButton.setIcon(images[clickedIndex / 4][clickedIndex % 4]);
clickedButton.setEnabled(false);
if (clickCount == 0) {
firstButton = clickedButton;
clickCount++;
} else {
secondButton = clickedButton;
if (firstButton.getIcon().equals(secondButton.getIcon())) {
pairsFound++;
score++;
if (pairsFound == 10) {
gameTime.stop();
JOptionPane.showMessageDialog(frame, "You won the game! Time: " + time + " seconds");
System.exit(0);
}
} else {
score--;
if (score == -10) {
gameTime.stop();
JOptionPane.showMessageDialog(frame, "Game Over! Score: " + score);
System.exit(0);
}
Timer timer = new Timer(1000, e1 -> {
firstButton.setIcon(empty);
firstButton.setEnabled(true);
secondButton.setIcon(empty);
secondButton.setEnabled(true);
});
timer.setRepeats(false);
timer.start();
}
clickCount = 0;
}
scoreLabel.setText("Score: " + score);
}
```
This method handles button click events, checks for matches, and updates the game state.
Block 15 - Main Method
```java
public static void main(String[] args) {
new MemoryGame();
}
```
The `main` method initializes the game by creating an instance of the `MemoryGame` class.
Conclusion
In conclusion, this Java memory game project offers a delightful blend of education and entertainment, making it a perfect choice for both novice and experienced Java programmers. By delving into the intricacies of Swing GUI, you've not only developed a captivating memory game but also honed your Java skills. Whether you're a student looking to enhance your programming abilities or a hobbyist eager to create fun games, this project has provided valuable insights and hands-on experience. We encourage you to explore further, expand your Java knowledge, and keep creating exciting projects. Happy coding!