board.java

package name= Snake-Game;

import java.awt.Color;
import java.awt.Dimension;
import java.awt.Font;
import java.awt.FontMetrics;
import java.awt.Graphics;
import java.awt.Toolkit;
import java.awt.event.ActionEvent;
import java.awt.event.ActionListener;
import java.awt.event.KeyAdapter;
import java.awt.event.KeyEvent;
import javax.swing.JPanel;
import javax.swing.Timer;

@SuppressWarnings("serial")
public class Board extends JPanel implements ActionListener {

private final static int BOARDWIDTH = 1000;
private final static int BOARDHEIGHT = 980;

private final static int PIXELSIZE = 25;

private final static int TOTALPIXELS = (BOARDWIDTH * BOARDHEIGHT)
        / (PIXELSIZE * PIXELSIZE);

private boolean inGame = true;

private Timer timer;

private static int speed = 45;

private Snake snake = new Snake();
private Food food = new Food();

public Board() {

    addKeyListener(new Keys());
    setBackground(Color.BLACK);
    setFocusable(true);

    setPreferredSize(new Dimension(BOARDWIDTH, BOARDHEIGHT));

    initializeGame();
}

@Override
protected void paintComponent(Graphics g) {
    super.paintComponent(g);

    draw(g);
}

void draw(Graphics g) {
    if (inGame == true) {
        g.setColor(Color.green);
        g.fillRect(food.getFoodX(), food.getFoodY(), PIXELSIZE, PIXELSIZE); // food

        for (int i = 0; i < snake.getJoints(); i++) {
            // Snake's head
            if (i == 0) {
                g.setColor(Color.RED);
                g.fillRect(snake.getSnakeX(i), snake.getSnakeY(i),
                        PIXELSIZE, PIXELSIZE);
                // Body of snake
            } else {
                g.fillRect(snake.getSnakeX(i), snake.getSnakeY(i),
                        PIXELSIZE, PIXELSIZE);
            }
        }

        Toolkit.getDefaultToolkit().sync();
    } else {
        endGame(g);
    }
}

void initializeGame() {
    snake.setJoints(3); // set our snake's initial size

    for (int i = 0; i < snake.getJoints(); i++) {
        snake.setSnakeX(BOARDWIDTH / 2);
        snake.setSnakeY(BOARDHEIGHT / 2);
    }
    snake.setMovingRight(true);

    food.createFood();

    timer = new Timer(speed, this);
    timer.start();
}

void checkFoodCollisions() {

    if ((proximity(snake.getSnakeX(0), food.getFoodX(), 20))
            && (proximity(snake.getSnakeY(0), food.getFoodY(), 20))) {

        System.out.println("intersection");
        snake.setJoints(snake.getJoints() + 1);
        food.createFood();
    }
}

void checkCollisions() {

    for (int i = snake.getJoints(); i > 0; i--) {

        if ((i > 5)
                && (snake.getSnakeX(0) == snake.getSnakeX(i) && (snake
                        .getSnakeY(0) == snake.getSnakeY(i)))) {
            inGame = false; // then the game ends
        }
    }

    if (snake.getSnakeY(0) >= BOARDHEIGHT) {
        inGame = false;
    }

    if (snake.getSnakeY(0) < 0) {
        inGame = false;
    }

    if (snake.getSnakeX(0) >= BOARDWIDTH) {
        inGame = false;
    }

    if (snake.getSnakeX(0) < 0) {
        inGame = false;
    }

    if (!inGame) {
        timer.stop();
    }
}

void endGame(Graphics g) {

    String message = "Game over";

    Font font = new Font("Times New Roman", Font.BOLD, 14);
    FontMetrics metrics = getFontMetrics(font);

    g.setColor(Color.red);
    g.setFont(font);

    g.drawString(message, (BOARDWIDTH - metrics.stringWidth(message)) / 2,
            BOARDHEIGHT / 2);

    System.out.println("Game Ended");

}
@Override
public void actionPerformed(ActionEvent e) {
    if (inGame == true) {

        checkFoodCollisions();
        checkCollisions();
        snake.move();

        System.out.println(snake.getSnakeX(0) + " " + snake.getSnakeY(0)
                + " " + food.getFoodX() + ", " + food.getFoodY());
    }
    repaint();
}

private class Keys extends KeyAdapter {

    @Override
    public void keyPressed(KeyEvent e) {

        int key = e.getKeyCode();

        if ((key == KeyEvent.VK_LEFT) && (!snake.isMovingRight())) {
            snake.setMovingLeft(true);
            snake.setMovingUp(false);
            snake.setMovingDown(false);
        }

        if ((key == KeyEvent.VK_RIGHT) && (!snake.isMovingLeft())) {
            snake.setMovingRight(true);
            snake.setMovingUp(false);
            snake.setMovingDown(false);
        }

        if ((key == KeyEvent.VK_UP) && (!snake.isMovingDown())) {
            snake.setMovingUp(true);
            snake.setMovingRight(false);
            snake.setMovingLeft(false);
        }

        if ((key == KeyEvent.VK_DOWN) && (!snake.isMovingUp())) {
            snake.setMovingDown(true);
            snake.setMovingRight(false);
            snake.setMovingLeft(false);
        }

        if ((key == KeyEvent.VK_ENTER) && (inGame == false)) {

            inGame = true;
            snake.setMovingDown(false);
            snake.setMovingRight(false);
            snake.setMovingLeft(false);
            snake.setMovingUp(false);

            initializeGame();
        }
    }
}

private boolean proximity(int a, int b, int closeness) {
    return Math.abs((long) a - b) <= closeness;
}

public static int getAllDots() {
    return TOTALPIXELS;
}

public static int getDotSize() {
    return PIXELSIZE;
}
}