java实现屏幕取色

      代码1。在屏幕上输出当前鼠标所在的屏幕颜色。
      import java.awt.*;

      public class PickColor {
      public static void main(String[] args) {
      PickColor pc = new PickColor();
      Color color = pc.pickColor();
      System.out.println("color = "+color);
      }

      public Color pickColor() {
      Color pixel = new Color(0,0,0);
      Robot robot = null;
      Point mousepoint;
      int R,G,B;
      // MouseInfo mouseinfo = new MouseInfo();
      try {
      robot = new Robot();
      } catch (AWTException e) {
      e.printStackTrace();
      System.exit(1);
      }
      mousepoint = MouseInfo.getPointerInfo().getLocation();
      pixel = robot.getPixelColor(mousepoint.x,mousepoint.y);
      R = pixel.getRed();
      G = pixel.getGreen();
      return pixel;
      }

      }

      代码2。使用一个GUI，输出当前鼠标所在的屏幕颜色，并改变GUI的背景色。
      // create by kin 2004/10/24 refer to http://dev.csdn.net/article/44/44529.shtm

      import java.awt.*;
      import java.awt.event.*;
      import javax.swing.*;
      import javax.swing.event.*;

      public class PickColor2 extends JFrame {
      public static void main(String[] args) {
      PickColor2 pc = new PickColor2();
      //Color color = pc.pickColor();
      //System.out.println("color = "+color);
      }

      public PickColor2 () {
      super("Pick Color");
      setSize(200,200);
      JPanel p =new JPanel();
      getContentPane().add(p);
      // this mouse listener only is limited in the java desktop region
      p.addMouseMotionListener(new PickColorMouesMotionListener(p));
      // this thread is really effected!
      new PickColorThread(p).start();
      setVisible(true); 
      }

      /**Mouse Motion Listener,when mouse are moving, then set corresping screens color to the JPanels background Color. */
      class PickColorMouesMotionListener extends MouseMotionAdapter {
      private JPanel p = null;
      PickColorMouesMotionListener(JPanel p) {
      this.p = p;
      }
      public void mouseMoved(MouseEvent e) {
      Color c = pickColor();
      this.p.setBackground(c);
      //System.out.println (c);
      }
      }

      class PickColorThread extends Thread {
      private JPanel p = null;
      PickColorThread(JPanel p){
      this.p=p;
      }
      public void run () {
      while (true) {
      try {
      Thread.currentThread().sleep(10);
      Color c = pickColor();

      this.p.setBackground(c);

      // try change the foreground when background s r <= 50 or g <= 50 or b <= 50
      Graphics g = p.getGraphics ();
      if (c.getRed() <=50 || c.getGreen() <= 50 || c.getBlue() <= 50) {
      g.setColor(Color.WHITE);
      } else {
      g.setColor(Color.BLACK);
      }
      g.drawString(c.toString(),0,100);
      g = null;

      //System.out.println (c);
      } catch (InterruptedException e) {
      e.printStackTrace();
      System.exit(1);
      }
      }
      }
      }

      /**Get Screen Color*/
      public Color pickColor() {
      Color pixel = new Color(0,0,0);
      Robot robot = null;
      Point mousepoint;
      int R,G,B;
      // MouseInfo mouseinfo = new MouseInfo();
      try {
      robot = new Robot();
      } catch (AWTException e) {
      e.printStackTrace();
      System.exit(1);
      }
      mousepoint = MouseInfo.getPointerInfo().getLocation();
      pixel = robot.getPixelColor(mousepoint.x,mousepoint.y);
      R = pixel.getRed();
      G = pixel.getGreen();
      return pixel;
      }

      }