public class GreedSnake {  public static void main(String[] args) {    SnakeModel model = new SnakeModel(20,30);    SnakeControl control = new SnakeControl(model);    SnakeView view = new SnakeView(model,control);    //添加一個觀察者，讓view成為model的觀察者    model.addObserver(view);       (new Thread(model)).start();  }}

package mvcTest;//SnakeControl.javaimport java.awt.event.KeyEvent;import java.awt.event.KeyListener;public class SnakeControl implements KeyListener{  SnakeModel model;  public SnakeControl(SnakeModel model){    this.model = model;  }  public void keyPressed(KeyEvent e) {    int keyCode = e.getKeyCode();    if (model.running){        // 運行狀態(tài)下，處理的按鍵      switch (keyCode) {        case KeyEvent.VK_UP:          model.changeDirection(SnakeModel.UP);          break;        case KeyEvent.VK_DOWN:          model.changeDirection(SnakeModel.DOWN);          break;        case KeyEvent.VK_LEFT:          model.changeDirection(SnakeModel.LEFT);          break;        case KeyEvent.VK_RIGHT:          model.changeDirection(SnakeModel.RIGHT);          break;        case KeyEvent.VK_ADD:        case KeyEvent.VK_PAGE_UP:          model.speedUp();          break;        case KeyEvent.VK_SUBTRACT:        case KeyEvent.VK_PAGE_DOWN:          model.speedDown();          break;        case KeyEvent.VK_SPACE:        case KeyEvent.VK_P:          model.changePauseState();          break;        default:      }    }    // 任何情況下處理的按鍵，按鍵導(dǎo)致重新啟動游戲    if (keyCode == KeyEvent.VK_R ||        keyCode == KeyEvent.VK_S ||        keyCode == KeyEvent.VK_ENTER) {      model.reset();    }  }  public void keyReleased(KeyEvent e) {  }  public void keyTyped(KeyEvent e) {  }}

package mvcTest;//SnakeModel.javaimport javax.swing.*;import java.util.Arrays;import java.util.LinkedList;import java.util.Observable;import java.util.Random;class SnakeModel extends Observable implements Runnable {  boolean[][] matrix;             // 指示位置上有沒蛇體或食物  LinkedList nodeArray = new LinkedList();  // 蛇體  Node food;  int maxX;  int maxY;  int direction = 2;             // 蛇運行的方向  boolean running = false;          // 運行狀態(tài)  int timeInterval = 200;           // 時間間隔，毫秒  double speedChangeRate = 0.75;       // 每次得速度變化率  boolean paused = false;           // 暫停標(biāo)志  int score = 0;               // 得分  int countMove = 0;             // 吃到食物前移動的次數(shù)  // UP and DOWN should be even  // RIGHT and LEFT should be odd  public static final int UP = 2;  public static final int DOWN = 4;  public static final int LEFT = 1;  public static final int RIGHT = 3;  public SnakeModel( int maxX, int maxY) {    this.maxX = maxX;    this.maxY = maxY;    reset();  }  public void reset(){    direction = SnakeModel.UP;       // 蛇運行的方向    timeInterval = 200;           // 時間間隔，毫秒    paused = false;             // 暫停標(biāo)志    score = 0;               // 得分    countMove = 0;             // 吃到食物前移動的次數(shù)    // initial matirx, 全部清0    matrix = new boolean[maxX][];    for (int i = 0; i < maxX; ++i) {      matrix[i] = new boolean[maxY];      Arrays.fill(matrix[i], false);    }    // initial the snake    // 初始化蛇體，如果橫向位置超過20個，長度為10，否則為橫向位置的一半    int initArrayLength = maxX > 20 ? 10 : maxX / 2;    nodeArray.clear();    for (int i = 0; i < initArrayLength; ++i) {      int x = maxX / 2 + i;//maxX被初始化為20      int y = maxY / 2;  //maxY被初始化為30      //nodeArray[x,y]: [10,15]-[11,15]-[12，15]~~[20,15]      //默認(rèn)的運行方向向上，所以游戲一開始nodeArray就變?yōu)椋?     //    [10，14]-[10，15]-[11，15]-[12，15]~~[19，15]      nodeArray.addLast(new Node(x, y));      matrix[x][y] = true;    }    // 創(chuàng)建食物    food = createFood();    matrix[food.x][food.y] = true;  }  public void changeDirection(int newDirection) {    // 改變的方向不能與原來方向同向或反向    if (direction % 2 != newDirection % 2) {      direction = newDirection;    }  }    public boolean moveOn() {    Node n = (Node) nodeArray.getFirst();    int x = n.x;    int y = n.y;    // 根據(jù)方向增減坐標(biāo)值    switch (direction) {      case UP:        y--;        break;      case DOWN:        y++;        break;      case LEFT:        x--;        break;      case RIGHT:        x++;        break;    }    // 如果新坐標(biāo)落在有效范圍內(nèi)，則進行處理    if ((0 <= x && x < maxX) && (0 <= y && y < maxY)) {          if (matrix[x][y]) {    // 如果新坐標(biāo)的點上有東西（蛇體或者食物）        if (x == food.x && y == food.y) {    // 吃到食物，成功          nodeArray.addFirst(food);      // 從蛇頭贈長          // 分?jǐn)?shù)規(guī)則，與移動改變方向的次數(shù)和速度兩個元素有關(guān)          int scoreGet = (10000 - 200 * countMove) / timeInterval;          score += scoreGet > 0 ? scoreGet : 10;          countMove = 0;          food = createFood();        // 創(chuàng)建新的食物          matrix[food.x][food.y] = true;   // 設(shè)置食物所在位置          return true;        } else                 // 吃到蛇體自身，失敗          return false;              } else {         // 如果新坐標(biāo)的點上沒有東西（蛇體），移動蛇體        nodeArray.addFirst(new Node(x, y));        matrix[x][y] = true;        n = (Node) nodeArray.removeLast();        matrix[n.x][n.y] = false;        countMove++;        return true;      }    }    return false;                  // 觸到邊線，失敗  }  public void run() {    running = true;    while (running) {      try {        Thread.sleep(timeInterval);      } catch (Exception e) {        break;      }      if (!paused) {        if (moveOn()) {          setChanged();      // Model通知View數(shù)據(jù)已經(jīng)更新          notifyObservers();        } else {          JOptionPane.showMessageDialog(null,              "you failed",              "Game Over",              JOptionPane.INFORMATION_MESSAGE);          break;        }      }    }    running = false;  }  private Node createFood() {    int x = 0;    int y = 0;    // 隨機獲取一個有效區(qū)域內(nèi)的與蛇體和食物不重疊的位置    do {      Random r = new Random();      x = r.nextInt(maxX);      y = r.nextInt(maxY);    } while (matrix[x][y]);    return new Node(x, y);  }  public void speedUp() {    timeInterval *= speedChangeRate;  }  public void speedDown() {    timeInterval /= speedChangeRate;  }  public void changePauseState() {    paused = !paused;  }  public String toString() {    String result = "";    for (int i = 0; i < nodeArray.size(); ++i) {      Node n = (Node) nodeArray.get(i);      result += "[" + n.x + "," + n.y + "]";    }    return result;  }}class Node {  int x;  int y;  Node(int x, int y) {    this.x = x;    this.y = y;  }}

package mvcTest;//SnakeView.javaimport javax.swing.*;import java.awt.*;import java.util.Iterator;import java.util.LinkedList;import java.util.Observable;import java.util.Observer;public class SnakeView implements Observer {  SnakeControl control = null;  SnakeModel model = null;  JFrame mainFrame;  Canvas paintCanvas;  JLabel labelScore;  public static final int canvasWidth = 200;  public static final int canvasHeight = 300;  public static final int nodeWidth = 10;  public static final int nodeHeight = 10;  public SnakeView(SnakeModel model, SnakeControl control) {    this.model = model;    this.control = control;    mainFrame = new JFrame("GreedSnake");    Container cp = mainFrame.getContentPane();    // 創(chuàng)建頂部的分?jǐn)?shù)顯示    labelScore = new JLabel("Score:");    cp.add(labelScore, BorderLayout.NORTH);    // 創(chuàng)建中間的游戲顯示區(qū)域    paintCanvas = new Canvas();    paintCanvas.setSize(canvasWidth + 1, canvasHeight + 1);    paintCanvas.addKeyListener(control);    cp.add(paintCanvas, BorderLayout.CENTER);    // 創(chuàng)建底下的幫助欄    JPanel panelButtom = new JPanel();    panelButtom.setLayout(new BorderLayout());    JLabel labelHelp;    labelHelp = new JLabel("PageUp, PageDown for speed;", JLabel.CENTER);    panelButtom.add(labelHelp, BorderLayout.NORTH);    labelHelp = new JLabel("ENTER or R or S for start;", JLabel.CENTER);    panelButtom.add(labelHelp, BorderLayout.CENTER);    labelHelp = new JLabel("SPACE or P for pause", JLabel.CENTER);    panelButtom.add(labelHelp, BorderLayout.SOUTH);    cp.add(panelButtom, BorderLayout.SOUTH);    mainFrame.addKeyListener(control);    mainFrame.pack();    mainFrame.setResizable(false);    mainFrame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);    mainFrame.setVisible(true);  }  void repaint() {    Graphics g = paintCanvas.getGraphics();    //draw background    g.setColor(Color.WHITE);    g.fillRect(0, 0, canvasWidth, canvasHeight);    // draw the snake    g.setColor(Color.BLACK);    LinkedList na = model.nodeArray;    Iterator it = na.iterator();    while (it.hasNext()) {      Node n = (Node) it.next();      drawNode(g, n);    }    // draw the food    g.setColor(Color.RED);    Node n = model.food;    drawNode(g, n);    updateScore();  }  private void drawNode(Graphics g, Node n) {    g.fillRect(n.x * nodeWidth,        n.y * nodeHeight,        nodeWidth - 1,        nodeHeight - 1);  }  public void updateScore() {    String s = "Score: " + model.score;    labelScore.setText(s);  }  public void update(Observable o, Object arg) {    repaint();  }}