import java.awt.Color;  import java.awt.Graphics;  import java.awt.Graphics2D;  import java.awt.Rectangle;  import java.awt.event.KeyAdapter;  import java.awt.event.KeyEvent;  import java.awt.image.BufferedImage;  import java.util.ArrayList;  import java.util.List;  import javax.swing.JFrame;    /**   * @url http://download.csdn.net/detail/leasystu/4308246   *    * @author Easy   */  public class InterFace extends JFrame {   public static final int WIDTH = 800, HEIGHT = 600, SLEEPTIME = 20, L = 1,     R = 2, U = 3, D = 4;   BufferedImage offersetImage = new BufferedImage(WIDTH, HEIGHT,     BufferedImage.TYPE_3BYTE_BGR);;   Rectangle rect = new Rectangle(20, 40, 15 * 50, 15 * 35);   Snake snake;   Node node;     public InterFace() {    snake = new Snake(this);    createNode();    this.setBounds(100, 100, WIDTH, HEIGHT);    this.addKeyListener(new KeyAdapter() {     public void keyPressed(KeyEvent arg0) {      System.out.println(arg0.getKeyCode());      switch (arg0.getKeyCode()) {      case KeyEvent.VK_LEFT:       snake.dir = L;       break;      case KeyEvent.VK_RIGHT:       snake.dir = R;       break;      case KeyEvent.VK_UP:       snake.dir = U;       break;      case KeyEvent.VK_DOWN:       snake.dir = D;      }     }    });    this.setTitle("贪吃蛇 0.1   By ： Easy");    this.setDefaultCloseOperation(EXIT_ON_CLOSE);    this.setVisible(true);    new Thread(new ThreadUpadte()).start();   }     public void paint(Graphics g) {    Graphics2D g2d = (Graphics2D) offersetImage.getGraphics();    g2d.setColor(Color.white);    g2d.fillRect(0, 0, WIDTH, HEIGHT);    g2d.setColor(Color.black);    g2d.drawRect(rect.x, rect.y, rect.width, rect.height);    if (snake.hit(node)) {     createNode();    }    snake.draw(g2d);    node.draw(g2d);    g.drawImage(offersetImage, 0, 0, null);   }     class ThreadUpadte implements Runnable {    public void run() {     while (true) {      try {       Thread.sleep(SLEEPTIME);       repaint();      } catch (InterruptedException e) {       e.printStackTrace();      }     }    }   }     public void createNode() {    int x = (int) (Math.random() * 650) + 50, y = (int) (Math.random() * 500) + 50;    Color color = Color.blue;    node = new Node(x, y, color);   }     public static void main(String args[]) {    new InterFace();   }  }    class Node {   int x, y, width = 15, height = 15;   Color color;     public Node(int x, int y, Color color) {    this(x, y);    this.color = color;   }     public Node(int x, int y) {    this.x = x;    this.y = y;    this.color = color.black;   }     public void draw(Graphics2D g2d) {    g2d.setColor(color);    g2d.drawRect(x, y, width, height);   }     public Rectangle getRect() {    return new Rectangle(x, y, width, height);   }  }    class Snake {   public List<Node> nodes = new ArrayList<Node>();   InterFace interFace;   int dir = InterFace.R;     public Snake(InterFace interFace) {    this.interFace = interFace;    nodes.add(new Node(20 + 150, 40 + 150));    addNode();   }     public boolean hit(Node node) {    for (int i = 0; i < nodes.size(); i++) {     if (nodes.get(i).getRect().intersects(node.getRect())) {      addNode();      return true;     }    }    return false;   }     public void draw(Graphics2D g2d) {    for (int i = 0; i < nodes.size(); i++) {     nodes.get(i).draw(g2d);    }    move();   }     public void move() {    nodes.remove((nodes.size() - 1));    addNode();   }     public synchronized void addNode() {    Node nodeTempNode = nodes.get(0);    switch (dir) {    case InterFace.L:     if (nodeTempNode.x <= 20) {      nodeTempNode = new Node(20 + 15 * 50, nodeTempNode.y);     }     nodes.add(0, new Node(nodeTempNode.x - nodeTempNode.width,       nodeTempNode.y));     break;    case InterFace.R:     if (nodeTempNode.x >= 20 + 15 * 50 - nodeTempNode.width) {      nodeTempNode = new Node(20 - nodeTempNode.width, nodeTempNode.y);     }     nodes.add(0, new Node(nodeTempNode.x + nodeTempNode.width,       nodeTempNode.y));     break;    case InterFace.U:     if (nodeTempNode.y <= 40) {      nodeTempNode = new Node(nodeTempNode.x, 40 + 15 * 35);     }     nodes.add(0, new Node(nodeTempNode.x, nodeTempNode.y       - nodeTempNode.height));     break;    case InterFace.D:     if (nodeTempNode.y >= 40 + 15 * 35 - nodeTempNode.height) {      nodeTempNode = new Node(nodeTempNode.x,        40 - nodeTempNode.height);     }     nodes.add(0, new Node(nodeTempNode.x, nodeTempNode.y       + nodeTempNode.height));     break;    }   }  }