ExampleDisplay.java

package fr.esir.project.sr.sweetsnake.client;

// -*- compile-command: "javac ExampleDisplay.java" -*- 

/* FT14Oct13
 *
 * A very basic example of key-driven movement in Java. Repaint not
 * optimized. Note there is no separation between interface and logic
 * (MVC pattern, etc.)
 */

import java.awt.Color;
import java.awt.Container;
import java.awt.Dimension;
import java.awt.Graphics;
import java.awt.event.KeyEvent;
import java.awt.event.KeyListener;
import java.util.HashMap;
import java.util.Map;
import java.util.Random;

import javax.swing.JComponent;
import javax.swing.JFrame;

abstract class AbstractGridShape extends JComponent
{

    /* Position of the shape in the grid */
    public int                   x = 0;
    public int                   y = 0;
    private final ExampleDisplay dis;

    public AbstractGridShape(ExampleDisplay display) {
        dis = display;
        dis.add(this);
        dis.pack(); // somehow needed or add does not work properly
    }

    /*
     * Set the positions of the shape in grid coordinates
     */
    public void setGridPos(int someX, int someY) {
        x = someX;
        y = someY;
    }

    abstract public void drawShape(Graphics g, int x, int y, int w, int h);

    /*
     * delegates drawing proper to drawShape. Transform the grid coordinates of
     * the shape into pixel coordinates, using the cell size of the
     * ExampleDisplay associated with the AbstractGridShape
     */
    @Override
    public void paint(Graphics g) {
        this.drawShape(g, dis.cellSize / 2 + x * dis.cellSize, dis.cellSize / 2 + y * dis.cellSize, dis.cellSize, dis.cellSize);
    }

    public void moveRect(int[] delta) {
        x = (x + delta[0] + dis.gridSize) % dis.gridSize;
        y = (y + delta[1] + dis.gridSize) % dis.gridSize;
    }
} // EndClass AbstractGridShape

class Rectangle extends AbstractGridShape
{
    public Rectangle(ExampleDisplay display) {
        super(display);
    }

    @Override
    public void drawShape(Graphics g, int x, int y, int w, int h) {
        g.setColor(Color.BLUE);
        g.fillRect(x, y, w, h);
    }
} // EndClass Rectangle

class Circle extends AbstractGridShape
{
    public Circle(ExampleDisplay display) {
        super(display);
    }

    @Override
    public void drawShape(Graphics g, int x, int y, int w, int h) {
        g.setColor(Color.RED);
        g.fillOval(x, y, w, h);
    }
} // EndClass Circle

public class ExampleDisplay extends JFrame implements KeyListener
{
    int                 cellSize       = 20;
    int                 gridSize       = 20;
    Map<Integer, int[]> moveTable      = new HashMap<Integer, int[]>();
    Rectangle           myRectangle    = new Rectangle(this);
    Container           myContainer;
    int                 numberOfSweets = 10;

    /*
     * gameMap contains the plan of the sweets to collect initialized to null by
     * default
     */
    Circle[][]          gameMap        = new Circle[gridSize][gridSize];

    public ExampleDisplay() {
        super();
        setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
        setResizable(false);
        setLocation(30, 30);
        myContainer = getContentPane();
        myContainer.setPreferredSize(new Dimension(cellSize * (gridSize + 1), cellSize * (gridSize + 1)));
        pack();

        // adding the red circles for a bit of landscape
        Random rand = new Random();

        for (int i = 0; i < numberOfSweets; i++) {
            int j, k;
            do {
                j = rand.nextInt(gridSize);
                k = rand.nextInt(gridSize);
            } while (gameMap[j][k] != null);

            gameMap[j][k] = new Circle(this);
            gameMap[j][k].setGridPos(j, k);
        } // EndFor i

        setVisible(true);

        moveTable.put(KeyEvent.VK_DOWN, new int[] { 0, +1 });
        moveTable.put(KeyEvent.VK_UP, new int[] { 0, -1 });
        moveTable.put(KeyEvent.VK_LEFT, new int[] { -1, 0 });
        moveTable.put(KeyEvent.VK_RIGHT, new int[] { +1, 0 });
        addKeyListener(this);

    } // EndConstructor ExampleDisplay

    /* needed to implement KeyListener */
    public void keyTyped(KeyEvent ke) {
    }

    public void keyReleased(KeyEvent ke) {
    }

    /* where the real work happens: reacting to key being pressed */
    public void keyPressed(KeyEvent ke) {
        int keyCode = ke.getKeyCode();
        if (!moveTable.containsKey(keyCode)) {
            return;
        }
        myRectangle.moveRect(moveTable.get(keyCode));
        if (gameMap[myRectangle.x][myRectangle.y] != null) {
            Circle c = gameMap[myRectangle.x][myRectangle.y];
            myContainer.remove(c);
            pack();
            gameMap[myRectangle.x][myRectangle.y] = null;
            numberOfSweets--;
            if (numberOfSweets == 0) {
                System.out.println("You've won. Congratulations!");
                System.exit(0);
            }
            System.out.println("Only " + numberOfSweets + " sweet(s) remaining...");
        }
        repaint();
    } // EndMethod keyPressed

    public static void main(String[] a) {
        JFrame window = new ExampleDisplay();
    } // EndMethod main
} // EndClass ExampleDisplay