每当客户端单击打印屏幕按钮时，我都需要捕获一个网页屏幕以将其存储在客户端计算机上。为此，我通过在jsp页面中嵌入带有签名的小程序（受信任的小程序）来进行搜索。因此，我正在尝试为独立的Java类使用一个简单的applet。成功后，我可以在签署了applet后尝试使用jsp。我试过的是：

import java.applet.Applet;  
import java.awt.Graphics;  
import java.util.Date;
import javax.imageio.ImageIO;
import java.awt.image.BufferedImage;
import java.io.File;
import java.awt.Dimension;
import java.awt.Rectangle;
import java.awt.Robot;
import java.awt.Toolkit;
import javax.swing.ImageIcon;
/* <applet code = MyApplet.class width="500" height="500">Java Applet for screen capture</applet>  */



public class MyApplet extends Applet {

  /* Applet Life cycle Methods */  
  public void start()
  { 
   try{
   // capture the whole screen
   BufferedImage screencapture = new Robot().createScreenCapture(new Rectangle(Toolkit.getDefaultToolkit().getScreenSize()) );
   // Save as JPEG
   File file = new File("D:/screencapture.jpg");
   ImageIO.write(screencapture, "jpg", file);
   System.out.println("screen capture finished : ");
     }//try closing...
     catch(Exception e)
     {
       System.out.println("screen capture error : ");
       e.printStackTrace();
     }//catch closing...  
   }//start closing...

 public void stop()
  {

  }   
}

我得到这个：

java.security.AccessControlException: access denied ("java.awt.AWTPermission" "createRobot")
        at java.security.AccessControlContext.checkPermission(AccessControlContext.java:366)
        at java.security.AccessController.checkPermission(AccessController.java:560)
        at java.lang.SecurityManager.checkPermission(SecurityManager.java:549)
        at java.awt.Robot.checkRobotAllowed(Robot.java:170)
        at java.awt.Robot.init(Robot.java:134)
        at java.awt.Robot.<init>(Robot.java:96)
        at MyApplet.start(MyApplet.java:23)
        at sun.applet.AppletPanel.run(AppletPanel.java:474)
        at java.lang.Thread.run(Thread.java:722)

任何帮助，任何想法都会得到应用。