APCS: AP Computer Science A @sfhs

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Snake Game

import java.awt.Color;
import java.awt.Font;
import java.awt.Graphics;
import java.awt.event.ActionEvent;
import java.awt.event.ActionListener;
import java.awt.event.KeyEvent;
import java.awt.event.KeyListener;
import javax.swing.JFrame;
import javax.swing.JPanel;
import javax.swing.Timer;

public class SnakeGame extends JPanel implements KeyListener, ActionListener
{
    public static int WIDTH=800;
    public static int HEIGHT=600;
    public static int SIZE=30;

    private Font titleFont, regularFont;
    private int x,y;
    private Timer timer;
    private Snake snake;

    public SnakeGame() 
    {

        snake = new Snake(WIDTH/2, HEIGHT/2, SIZE);
        titleFont = new Font("Roman", Font.BOLD, 18);
        regularFont = new Font("Helvetica", Font.PLAIN, 12);
        y=0;
        x=200;
        timer = new Timer(10, this); //1000=1 seconds	
        timer.start();

    }

    public static void main(String[] args) {
        SnakeGame app= new SnakeGame();
        JFrame window = new JFrame("Snake Version 0.1");
        window.setSize(WIDTH, HEIGHT);
        window.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
        window.getContentPane().add(app);
        window.addKeyListener(app);
        //window.pack();
        window.setVisible(true);

    }

    public void paintComponent(Graphics g){
        super.paintComponent(g);
        g.setColor(Color.WHITE);
        g.fillRect(0, 0, getWidth(),getHeight());
        g.setColor(Color.BLUE);
        g.setFont(titleFont);
        g.drawString("SnakeGame Example", 20, 20);
        g.setColor(Color.BLACK);
        g.setFont(regularFont);
        snake.draw(g);

    }

    // These 3 methods need to be declares to implement the KeyListener Interface
    @Override
    public void keyTyped(KeyEvent e) {}

    @Override
    public void keyPressed(KeyEvent e) {
        int code=e.getKeyCode();

        if (code ==39) // right
            snake.changeDirection('e');
        else if (code == 37 ) //left
            snake.changeDirection('w');
        else if (code == 38 ) //left
            snake.changeDirection('n');
        else if (code == 40 ) //left
            snake.changeDirection('s');

        repaint();
    }

    @Override
    public void keyReleased(KeyEvent e) {}

    @Override
    public void actionPerformed(ActionEvent e) {

        if (e.getSource()==timer){
            snake.move();
        }
        repaint();
    }

}

import java.awt.*;

public class Snake
{
    // instance variables - replace the example below with your own
    private int x, y, size;
    
    private char direction;
    
    /**
     * Constructor for objects of class Snake
     */
    public Snake(int x, int y, int size)
    {
        // initialise instance variables
        this.x = x;
        this.y = y;
        this.size = size;
        direction = 'e';
    }
    public void draw(Graphics g)
    {
        
       g.setColor(Color.GREEN);
       if (direction == 'e' || direction== 'w')
           g.fillOval(x, y, 2*size,size); 
       else 
           g.fillOval(x, y, size,2*size); 
    }
    /**
     * An example of a method - replace this comment with your own
     * 
     * @param  y   a sample parameter for a method
     * @return     the sum of x and y 
     */
    public void move()
    {
        if (direction == 'e')
            x++;
        else if (direction == 'w')
            x--;
        else if (direction == 'n')
            y--;
        else if (direction == 's')
            y++;
            
    }
    public void changeDirection(char ch)
    {
        direction = ch;
    }
}