/* 主要使用的是java.util.Robot类来捕获屏幕,

* 可以实现对屏幕一个矩形区域的捕获,通过这个类,

* 我们也可以实现一个远程桌面控制的程序

*/

package com.qiu.util;

import java.io.*;

import java.net.*;

import javax.swing.*;

import java.awt.*;

import java.awt.event.*;

import java.awt.image.*;

import javax.imageio.*;

import java.io.*;

public class ScreenCapture {

//test main

public static void main(String[] args) throws Exception{

String userdir = System.getProperty("user.dir");

File tempFile = new File("d:","temp.png");

ScreenCapture capture = ScreenCapture.getInstance();

capture.captureImage();

JFrame frame = new JFrame();

JPanel panel = new JPanel();

panel.setLayout(new BorderLayout());

JLabel imagebox = new JLabel();

panel.add(BorderLayout.CENTER,imagebox);

imagebox.setIcon(capture.getPickedIcon());

capture.saveToFile(tempFile);

capture.captureImage();

imagebox.setIcon(capture.getPickedIcon());

frame.setContentPane(panel);

frame.setSize(400,300);

frame.show();

System.out.println("Over");

}

private ScreenCapture() {

try{

robot = new Robot();

}

catch(AWTException e) {

System.err.println("Internal Error: " + e);

e.printStackTrace();

}

JPanel cp = (JPanel)dialog.getContentPane();

cp.setLayout(new BorderLayout());

labFullScreenImage.addMouseListener(new MouseAdapter() {

public void mouseReleased(MouseEvent evn) {

isFirstPoint = true;

pickedImage = fullScreenImage.getSubimage(recX,recY,recW,recH);

dialog.setVisible(false);

}

});

labFullScreenImage.addMouseMotionListener(new MouseMotionAdapter() {

public void mouseDragged(MouseEvent evn) {

if(isFirstPoint) {

x1 = evn.getX();

y1 = evn.getY();

isFirstPoint = false;

}

else {

x2 = evn.getX();

y2 = evn.getY();

int maxX = Math.max(x1,x2);

int maxY = Math.max(y1,y2);

int minX = Math.min(x1,x2);

int minY = Math.min(y1,y2);

recX = minX;

recY = minY;

recW = maxX-minX;

recH = maxY-minY;

labFullScreenImage.drawRectangle(recX,recY,recW,recH);

}

}

public void mouseMoved(MouseEvent e) {

labFullScreenImage.drawCross(e.getX(),e.getY());

}

});

cp.add(BorderLayout.CENTER,labFullScreenImage);

dialog.setCursor(Cursor.getPredefinedCursor(Cursor.CROSSHAIR_CURSOR));

dialog.setAlwaysOnTop(true);

dialog.setMaximumSize(

Toolkit.getDefaultToolkit().getScreenSize());

dialog.setUndecorated(true);

dialog.setSize(dialog.getMaximumSize());

dialog.setModal(true);

}

//Singleton Pattern

public static ScreenCapture getInstance() {

return defaultCapturer;

}

/**捕捉全屏慕*/

public Icon captureFullScreen() {

fullScreenImage = robot.createScreenCapture(new Rectangle(

Toolkit.getDefaultToolkit().getScreenSize()));

ImageIcon icon = new ImageIcon(fullScreenImage);

return icon;

}

/**捕捉屏幕的一个矫形区域

*/

public void captureImage() {

fullScreenImage = robot.createScreenCapture(new Rectangle(

Toolkit.getDefaultToolkit().getScreenSize()));

ImageIcon icon = new ImageIcon(fullScreenImage);

labFullScreenImage.setIcon(icon);

dialog.setVisible(true);

}

/**得到捕捉后的BufferedImage*/

public BufferedImage getPickedImage() {

return pickedImage;

}

/**得到捕捉后的Icon*/

public ImageIcon getPickedIcon() {

return new ImageIcon(getPickedImage());

}

/**储存为一个文件,为PNG格式

*@deprecated

*replaced by saveAsPNG(File file)

**/

@Deprecated

public void saveToFile(File file) throws IOException{

ImageIO.write(getPickedImage(),defaultImageFormater,file);

}

/**储存为一个文件,为PNG格式*/

public void saveAsPNG(File file) throws IOException {

ImageIO.write(getPickedImage(),"png",file);

}

/**储存为一个JPEG格式图像文件*/

public void saveAsJPEG(File file) throws IOException {

ImageIO.write(getPickedImage(),"JPEG",file);

}

/**写入一个OutputStream*/

public void write(OutputStream out) throws IOException{

ImageIO.write(getPickedImage(),defaultImageFormater,out);

}

//singleton design pattern

private static ScreenCapture defaultCapturer = new ScreenCapture();

private int x1,y1,x2,y2;

private int recX,recY,recH,recW; //截取的图像

private boolean isFirstPoint   = true;

private BackgroundImage labFullScreenImage = new BackgroundImage();

private Robot robot;

private BufferedImage fullScreenImage;

private BufferedImage pickedImage;

private String defaultImageFormater = "png";

private JDialog dialog = new JDialog();

}

/**显示图片的Label*/

class BackgroundImage extends JLabel{

public void paintComponent(Graphics g) {

super.paintComponent(g);

g.drawRect(x,y,w,h);

String area = Integer.toString(w)+" * "+ Integer.toString(h);

g.drawString(area,x+(int)w/2-15,y+(int)h/2);

g.drawLine(lineX,0,lineX,getHeight());

g.drawLine(0,lineY,getWidth(),lineY);

}

public void drawRectangle(int x,int y,int width,int height) {

this.x = x;

this.y = y;

h = height;

w = width;

repaint();

}

public void drawCross(int x,int y) {

lineX = x;

lineY = y;

repaint();

}

int lineX,lineY;

int x,y,h,w;

}