基礎入門:Java的Robot類實現抓屏

主要使用的是java.util.Robot類來捕獲屏幕，可以實現對屏幕一個矩形區(qū)域的捕獲，通過這個類，我們也可以實現一個遠程桌面控制的程序。主要使用的是java.util.Robot類來捕獲屏幕,可以實現對屏幕一個矩形區(qū)域的捕獲,通過這個類,我們也可以實現一個遠程桌面控制的程序。
    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.*;
    /** *//**@Author Qiu_BaiChao
    *一個簡單的屏幕抓圖
    如抓取http://www.bt285.cn/content.php?id=1196863 中的甜性澀愛的照片。
    *
    **/
    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;
    }
    /** *//**捕捉屏幕的一個矯形區(qū)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());
    }
    /** *//**儲存為一個文件,為PNG格式
    *@deprecated
    *replaced by saveAsPNG(File file)
    **/
    @Deprecated
    public void saveToFile(File file) throws IOException{
    ImageIO.write(getPickedImage(),defaultImageFormater,file);
    }
    /** *//**儲存為一個文件,為PNG格式*/
    public void saveAsPNG(File file) throws IOException {
    ImageIO.write(getPickedImage(),"png",file);
    }
    /** *//**儲存為一個JPEG格式圖像文件*/
    public void saveAsJPEG(File file) throws IOException {
    ImageIO.write(getPickedImage(),"JPEG",file);