Java应用程序实现屏幕的"拍照"

package Camera;
import java.awt.image.BufferedImage;
import java.io.*;
import javax.imageio.*;
import java.awt.*;
/*******************************************************************
 * 该JavaBean可以直接在其他Java应用程序中调用，实现屏幕的"拍照"
 * This JavaBean is used to snapshot the GUI in a 
 * Java application! You can embeded
 * it in to your java application source code, and us
 * it to snapshot the right GUI of the application
 * @see javax.ImageIO
 * @author Visec·Dana
 * @version 1.0
 *****************************************************/
public class GuiCamera {
    private String fileName; //文件的前缀
    private String defaultName = "GuiCamera";
    static int serialNum=0;
    private String imageFormat; //图像文件的格式
    private String defaultImageFormat="png";
    Dimension d=Toolkit.getDefaultToolkit().getScreenSize();

    /****************************************************************
     * 默认的文件前缀为GuiCamera，文件格式为PNG格式
     * The default construct will use the default 
     * Image file surname "GuiCamera", 
     * and default image format "png"
     ****************************************************************/
    public GuiCamera() {
        fileName = defaultName;
        imageFormat=defaultImageFormat;

    }
    /****************************************************************
     * @param s the surname of the snapshot file
     * @param format the format of the  image file, 
     * it can be "jpg" or "png"
     * 本构造支持JPG和PNG文件的存储
     ****************************************************************/
    public GuiCamera(String s,String format){
        fileName = s;
        imageFormat=format;
    }
    /****************************************************************
     * 对屏幕进行拍照
     * snapShot the Gui once
     ****************************************************************/
    public void snapShot(){
        try {
            //拷贝屏幕到一个BufferedImage对象screenshot
            BufferedImage screenshot = (new Robot()).createScreenCapture(new Rectangle(0, 0, (int) d.getWidth(), (int) d.getHeight()));
            //根据文件前缀变量和文件格式变量，自动生成文件名
            String name=fileName+String.valueOf(serialNum)+"."+imageFormat;
            File f = new File(name);
            System.out.print("Save File "+name);
            //将screenshot对象写入图像文件
            ImageIO.write(screenshot, imageFormat, f);
            System.out.print("..Finished!\n");
        }
        catch (Exception ex) {
            System.out.println(ex);
        }
    }
}

package Camera;
import java.text.SimpleDateFormat;
import java.util.Date;
/***
 * 实现屏幕的"拍照"
 * @author Visec·Dana
 */
public class Client{
    public static void main(String[] args) {
        Date date=new Date();
        SimpleDateFormat df=new SimpleDateFormat("yyyy-MM-dd-HH-mm");
        GuiCamera cam= new GuiCamera("F://"+df.format(date), "png"); 
        cam.snapShot();
    }
}