JAVA截屏程序(第四版)_java程序5-4截图-优快云博客

昨天看到留言,于是今天又把一些功能加进进去了

比如,
1,程序可以最小化到系统托盘区
2,程序可以批量保存所有截过的图片
3,修正了以前的一个小BUG,那就是输入保存图片的文件名时,如果没有输入后缀名,将保存正常,如果输入了后缀名,将会保存格式出错
打包文件请点击这里下载,dist文件夹里面的JAR文件是可以双击执行的

感谢朋友们的建议,谢谢.

/*
* CaptureScreen.java
*
* Created on 2007年8月30日, 下午12:46
*
* To change this template, choose Tools | Template Manager
* and open the template in the editor.
*/

package hadeslee.swing;

/**
*
* @author lbf
*/
import java.awt. * ;
import java.awt.datatransfer.DataFlavor;
import java.awt.datatransfer.Transferable;
import java.awt.datatransfer.UnsupportedFlavorException;
import java.awt.event. * ;
import javax.swing. * ;
import java.io. * ;
import javax.imageio. * ;
import java.awt.image. * ;

public class CaptureScreen extends JFrame implements ActionListener{
 private JButton start,cancel,saveAll;
 private JPanel c;
 private BufferedImage get;
 private JTabbedPane jtp; // 一个放置很多份图片
 private int index; // 一个一直会递增的索引,用于标认图片
 private JRadioButton java,system; // JAVA界面,系统界面
 /** Creates a new instance of CaptureScreen */
 public CaptureScreen() {
 super ( " 屏幕截取软件(第三版) " );
 try {
 UIManager.setLookAndFeel(UIManager.getSystemLookAndFeelClassName());
 } catch (Exception exe){
 exe.printStackTrace();
 }
 initWindow();
 initOther();
 initTrayIcon();
 }
 private void initOther(){
 jtp = new JTabbedPane(JTabbedPane.TOP,JTabbedPane.SCROLL_TAB_LAYOUT);
 }
 private void initWindow(){
 start = new JButton( " 开始截取 " );
 saveAll = new JButton( " 保存所有 " );
 cancel = new JButton( " 退出 " );
 start.addActionListener( this );
 saveAll.addActionListener( this );
 cancel.addActionListener( this );
 JPanel buttonJP = new JPanel();
 c = new JPanel( new BorderLayout());
 c.setBackground(Color.BLACK);
 JLabel jl = new JLabel( " 屏幕截取 " ,JLabel.CENTER);
 JLabel jl1 = new JLabel( " <Html>作者：千里冰封 " +
 " QQ:24325142 </html> " ,JLabel.CENTER);
 jl.setFont( new Font( " 黑体 " ,Font.BOLD, 40 ));
 jl.setForeground(Color.RED);
 jl1.setForeground(Color.BLUE);
 c.add(jl,BorderLayout.CENTER);
 c.add(jl1,BorderLayout.SOUTH);
 buttonJP.add(start);
 buttonJP.add(saveAll);
 buttonJP.add(cancel);
 buttonJP.setBorder(BorderFactory.createTitledBorder( " 公共操作区 " ));
 JPanel jp = new JPanel(); // 放两个单选按钮的面板
 jp.add(java = new JRadioButton( " java界面 " ));
 jp.add(system = new JRadioButton( " 系统界面 " , true ));
 java.addActionListener( this );
 system.addActionListener( this );
 jp.setBorder(BorderFactory.createTitledBorder( " 界面风格 " ));
 ButtonGroup bg = new ButtonGroup();
 bg.add(java);
 bg.add(system);
 JPanel all = new JPanel();
 all.add(jp);
 all.add(buttonJP);
 this .getContentPane().add(c,BorderLayout.CENTER);
 this .getContentPane().add(all,BorderLayout.SOUTH);
 this .setSize( 500 , 400 );
 this .setLocationRelativeTo( null );
 this .setVisible( true );
 this .setAlwaysOnTop( true );
 this .setDefaultCloseOperation(JFrame.DO_NOTHING_ON_CLOSE);
 this .addWindowListener( new WindowAdapter(){
 public void windowClosing(WindowEvent we){
 CaptureScreen. this .setVisible( false );
 }
 });
 }
 private void initTrayIcon(){
 try {
 SystemTray st = SystemTray.getSystemTray();
 Image im = ImageIO.read( this .getClass().getResource( " bg.gif " ));
 PopupMenu pm = new PopupMenu( " 弹出菜单 " );
 pm.add( new MenuItem( " 关于 " )).addActionListener( new ActionListener(){
 public void actionPerformed(ActionEvent ae){
 JOptionPane.showMessageDialog(CaptureScreen. this , " <html><center><h2>关于</h2></center> " +
 " 这是一款纯JAVA的屏幕截取程序 在以前的基础上增加了一些常用的功能, " +
 " 比如,批量保存,多幅截取,复制到系统粘帖板

" +
 " 在使用过程中有任何问题,欢迎联系. " +
 " 作者:千里冰封 " +
 " QQ:24325142 </html> " );
 }
 });
 pm.addSeparator();
 pm.add( new MenuItem( " 显示主窗口 " )).addActionListener( new ActionListener(){
 public void actionPerformed(ActionEvent ae){
 CaptureScreen. this .setVisible( true );
 }
 });
 pm.add( new MenuItem( " 开始截取 " )).addActionListener( new ActionListener(){
 public void actionPerformed(ActionEvent ae){
 doStart();
 }
 });
 pm.add( new MenuItem( " 退出程序 " )).addActionListener( new ActionListener(){
 public void actionPerformed(ActionEvent ae){
 System.exit( 0 );
 }
 });
 TrayIcon ti = new TrayIcon(im, " JAVA屏幕截取 " ,pm);
 st.add(ti);
 ti.addActionListener( new ActionListener(){
 public void actionPerformed(ActionEvent ae){
 CaptureScreen. this .setVisible( true );
 }
 });
 } catch (Exception exe){
 exe.printStackTrace();
 }
 }
 private void updates(){
 this .setVisible( true );
 if (get != null ){
 // 如果索引是0,则表示一张图片都没有被加入过,
 // 则要清除当前的东西,重新把tabpane放进来
 if (index == 0 ){
 c.removeAll();
 c.add(jtp,BorderLayout.CENTER);
 } else { // 否则的话,直接对tabpane添加面板就可以了
 // 就什么都不用做了
 }
 PicPanel pic = new PicPanel(get);
 jtp.addTab( " 图片 " + ( ++ index),pic);
 jtp.setSelectedComponent(pic);
 SwingUtilities.updateComponentTreeUI(c);
 }
 }
 private void doStart(){
 try {
 this .setVisible( false );
 Thread.sleep( 500 ); // 睡500毫秒是为了让主窗完全不见
 Robot ro = new Robot();
 Toolkit tk = Toolkit.getDefaultToolkit();
 Dimension di = tk.getScreenSize();
 Rectangle rec = new Rectangle( 0 , 0 ,di.width,di.height);
 BufferedImage bi = ro.createScreenCapture(rec);
 JFrame jf = new JFrame();
 Temp temp = new Temp(jf,bi,di.width,di.height);
 jf.getContentPane().add(temp,BorderLayout.CENTER);
 jf.setUndecorated( true );
 jf.setSize(di);
 jf.setVisible( true );
 jf.setAlwaysOnTop( true );
 } catch (Exception exe){
 exe.printStackTrace();
 }
 }
 /**
 *公共方法,处理保存所有的图片
 */
 public void doSaveAll(){
 if (jtp.getTabCount() == 0 ){
 JOptionPane.showMessageDialog( this , " 图片不能为空!! " , " 错误 " ,JOptionPane.ERROR_MESSAGE);
 return ;
 }
 JFileChooser jfc = new JFileChooser( " . " );
 jfc.addChoosableFileFilter( new GIFfilter());
 jfc.addChoosableFileFilter( new BMPfilter());
 jfc.addChoosableFileFilter( new JPGfilter());
 jfc.addChoosableFileFilter( new PNGfilter());
 int i = jfc.showSaveDialog( this );
 if (i == JFileChooser.APPROVE_OPTION){
 File file = jfc.getSelectedFile();
 String about = " PNG " ;
 String ext = file.toString().toLowerCase();
 javax.swing.filechooser.FileFilter ff = jfc.getFileFilter();
 if (ff instanceof JPGfilter){
 about = " JPG " ;
 } else if (ff instanceof PNGfilter){
 about = " PNG " ;
 } else if (ff instanceof BMPfilter){
 about = " BMP " ;
 } else if (ff instanceof GIFfilter){
 about = " GIF " ;
 }
 if (ext.endsWith(about.toLowerCase())){
 ext = ext.substring( 0 ,ext.lastIndexOf(about.toLowerCase()));
 }
 // 起一个线程去保存这些图片并显示出进度条
 new SaveAllThread(ext,about).setVisible( true );
 }

 }
 // 专门用来保存所有图片的线程类,它还要显示出保存的进度条
 private class SaveAllThread extends JDialog implements Runnable{
 private String name; // 文件名头部份
 private String ext; // 文件格式
 private JProgressBar jpb; // 一个进度条
 private JLabel info; // 一个信息显示条
 private int allTask,doneTask; // 所有任务,已完成任务
 public SaveAllThread(String name,String ext){
 super (CaptureScreen. this , " 保存 " , true );
 this .name = name;
 this .ext = ext;
 initWindow();
 }
 private void initWindow(){
 jpb = new JProgressBar();
 allTask = jtp.getTabCount();
 jpb.setMaximum(allTask);
 jpb.setMinimum( 0 );
 jpb.setValue( 0 );
 jpb.setStringPainted( true );
 setProgressBarString();
 info = new JLabel( " 正在保存到: " );
 this .getContentPane().setBackground(Color.CYAN);
 this .add(info,BorderLayout.NORTH);
 this .add(jpb,BorderLayout.SOUTH);
 this .setUndecorated( true );
 this .setSize( 300 , 100 );
 this .setLocationRelativeTo(CaptureScreen. this );
 new Thread( this ).start();
 }
 private void setProgressBarString(){
 jpb.setString( "" + doneTask + " / " + allTask);
 }
 public void run(){
 try {
 for ( int i = 0 ;i < allTask;i ++ ){
 PicPanel pp = (PicPanel)jtp.getComponentAt(i);
 BufferedImage image = pp.getImage();
 File f = new File(name + (doneTask + 1 ) + " . " + ext.toLowerCase());
 info.setText( " <html>正在保存到: " + f.toString() + " </html> " );
 ImageIO.write(image,ext,f);
 doneTask ++ ;
 jpb.setValue(doneTask);
 setProgressBarString();
 Thread.sleep( 500 );
 }
 JOptionPane.showMessageDialog( this , " 保存完毕!! " );
 this .dispose();
 } catch (Exception exe){
 exe.printStackTrace();
 this .dispose();
 }
 }
 }
 /**
 *公用的处理保存图片的方法
 *这个方法不再私有了
 */
 public void doSave(BufferedImage get){
 try {
 if (get == null ){
 JOptionPane.showMessageDialog( this , " 图片不能为空!! " , " 错误 " ,JOptionPane.ERROR_MESSAGE);
 return ;
 }
 JFileChooser jfc = new JFileChooser( " . " );
 jfc.addChoosableFileFilter( new GIFfilter());
 jfc.addChoosableFileFilter( new BMPfilter());
 jfc.addChoosableFileFilter( new JPGfilter());
 jfc.addChoosableFileFilter( new PNGfilter());
 int i = jfc.showSaveDialog( this );
 if (i == JFileChooser.APPROVE_OPTION){
 File file = jfc.getSelectedFile();
 String about = " PNG " ;
 String ext = file.toString().toLowerCase();
 javax.swing.filechooser.FileFilter ff = jfc.getFileFilter();
 if (ff instanceof JPGfilter){
 about = " JPG " ;
 if ( ! ext.endsWith( " .jpg " )){
 String ns = ext + " .jpg " ;
 file = new File(ns);
 }
 } else if (ff instanceof PNGfilter){
 about = " PNG " ;
 if ( ! ext.endsWith( " .png " )){
 String ns = ext + " .png " ;
 file = new File(ns);

 }
 } else if (ff instanceof BMPfilter){
 about = " BMP " ;
 if ( ! ext.endsWith( " .bmp " )){
 String ns = ext + " .bmp " ;
 file = new File(ns);

 }
 } else if (ff instanceof GIFfilter){
 about = " GIF " ;
 if ( ! ext.endsWith( " .gif " )){
 String ns = ext + " .gif " ;
 file = new File(ns);

 }
 }
 if (ImageIO.write(get,about,file)){
 JOptionPane.showMessageDialog( this , " 保存成功！ " );
 } else
 JOptionPane.showMessageDialog( this , " 保存失败！ " );
 }
 } catch (Exception exe){
 exe.printStackTrace();
 }
 }
 /**
 *公共的处理把当前的图片加入剪帖板的方法
 */
 public void doCopy( final BufferedImage image){
 try {
 if (get == null ){
 JOptionPane.showMessageDialog( this , " 图片不能为空!! " , " 错误 " ,JOptionPane.ERROR_MESSAGE);
 return ;
 }
 Transferable trans = new Transferable(){
 public DataFlavor[] getTransferDataFlavors() {
 return new DataFlavor[] { DataFlavor.imageFlavor };
 }
 public boolean isDataFlavorSupported(DataFlavor flavor) {
 return DataFlavor.imageFlavor.equals(flavor);
 }
 public Object getTransferData(DataFlavor flavor) throws UnsupportedFlavorException, IOException {
 if (isDataFlavorSupported(flavor))
 return image;
 throw new UnsupportedFlavorException(flavor);
 }

 };
 Toolkit.getDefaultToolkit().getSystemClipboard().setContents(trans, null );
 JOptionPane.showMessageDialog( this , " 已复制到系统粘帖板!! " );
 } catch (Exception exe){
 exe.printStackTrace();
 JOptionPane.showMessageDialog( this , " 复制到系统粘帖板出错!! " , " 错误 " ,JOptionPane.ERROR_MESSAGE);
 }
 }
 // 处理关闭事件
 private void doClose(Component c){
 jtp.remove(c);
 c = null ;
 System.gc();
 }
 public void actionPerformed(ActionEvent ae){
 Object source = ae.getSource();
 if (source == start){
 doStart();
 } else if (source == cancel){
 System.exit( 0 );
 } else if (source == java){
 try {
 UIManager.setLookAndFeel(UIManager.getCrossPlatformLookAndFeelClassName());
 SwingUtilities.updateComponentTreeUI( this );
 } catch (Exception exe){
 exe.printStackTrace();
 }
 } else if (source == system){
 try {
 UIManager.setLookAndFeel(UIManager.getSystemLookAndFeelClassName());
 SwingUtilities.updateComponentTreeUI( this );
 } catch (Exception exe){
 exe.printStackTrace();
 }
 } else if (source == saveAll){
 doSaveAll();
 }
 }
 // 一个内部类,它表示一个面板,一个可以被放进tabpane的面板
 // 也有自己的一套处理保存和复制的方法
 private class PicPanel extends JPanel implements ActionListener{
 JButton save,copy,close; // 表示保存,复制,关闭的按钮
 BufferedImage get; // 得到的图片
 public PicPanel(BufferedImage get){
 super ( new BorderLayout());
 this .get = get;
 initPanel();
 }
 public BufferedImage getImage(){
 return get;
 }
 private void initPanel(){
 save = new JButton( " 保存(S) " );
 copy = new JButton( " 复制到剪帖板(C) " );
 close = new JButton( " 关闭(X) " );
 save.setMnemonic( ' S ' );
 copy.setMnemonic( ' C ' );
 close.setMnemonic( ' X ' );
 JPanel buttonPanel = new JPanel();
 buttonPanel.add(copy);
 buttonPanel.add(save);
 buttonPanel.add(close);
 JLabel icon = new JLabel( new ImageIcon(get));
 this .add( new JScrollPane(icon),BorderLayout.CENTER);
 this .add(buttonPanel,BorderLayout.SOUTH);
 save.addActionListener( this );
 copy.addActionListener( this );
 close.addActionListener( this );
 }
 public void actionPerformed(ActionEvent e) {
 Object source = e.getSource();
 if (source == save){
 doSave(get);
 } else if (source == copy){
 doCopy(get);
 } else if (source == close){
 get = null ;
 doClose( this );
 }
 }
 }
 // 保存BMP格式的过滤器
 private class BMPfilter extends javax.swing.filechooser.FileFilter{
 public BMPfilter(){

 }
 public boolean accept(File file){
 if (file.toString().toLowerCase().endsWith( " .bmp " ) ||
 file.isDirectory()){
 return true ;
 } else
 return false ;
 }
 public String getDescription(){
 return " *.BMP(BMP图像) " ;
 }
 }
 // 保存JPG格式的过滤器
 private class JPGfilter extends javax.swing.filechooser.FileFilter{
 public JPGfilter(){

 }
 public boolean accept(File file){
 if (file.toString().toLowerCase().endsWith( " .jpg " ) ||
 file.isDirectory()){
 return true ;
 } else
 return false ;
 }
 public String getDescription(){
 return " *.JPG(JPG图像) " ;
 }
 }
 // 保存GIF格式的过滤器
 private class GIFfilter extends javax.swing.filechooser.FileFilter{
 public GIFfilter(){

 }
 public boolean accept(File file){
 if (file.toString().toLowerCase().endsWith( " .gif " ) ||
 file.isDirectory()){
 return true ;
 } else
 return false ;
 }
 public String getDescription(){
 return " *.GIF(GIF图像) " ;
 }
 }

 // 保存PNG格式的过滤器
 private class PNGfilter extends javax.swing.filechooser.FileFilter{
 public boolean accept(File file){
 if (file.toString().toLowerCase().endsWith( " .png " ) ||
 file.isDirectory()){
 return true ;
 } else
 return false ;
 }
 public String getDescription(){
 return " *.PNG(PNG图像) " ;
 }
 }
 // 一个暂时类，用于显示当前的屏幕图像
 private class Temp extends JPanel implements MouseListener,MouseMotionListener{
 private BufferedImage bi;
 private int width,height;
 private int startX,startY,endX,endY,tempX,tempY;
 private JFrame jf;
 private Rectangle select = new Rectangle( 0 , 0 , 0 , 0 ); // 表示选中的区域
 private Cursor cs = new Cursor(Cursor.CROSSHAIR_CURSOR); // 表示一般情况下的鼠标状态
 private States current = States.DEFAULT; // 表示当前的编辑状态
 private Rectangle[] rec; // 表示八个编辑点的区域
 // 下面四个常量,分别表示谁是被选中的那条线上的端点
 public static final int START_X = 1 ;
 public static final int START_Y = 2 ;
 public static final int END_X = 3 ;
 public static final int END_Y = 4 ;
 private int currentX,currentY; // 当前被选中的X和Y,只有这两个需要改变
 private Point p = new Point(); // 当前鼠标移的地点
 private boolean showTip = true ; // 是否显示提示.如果鼠标左键一按,则提示不再显了
 public Temp(JFrame jf,BufferedImage bi, int width, int height){
 this .jf = jf;
 this .bi = bi;
 this .width = width;
 this .height = height;
 this .addMouseListener( this );
 this .addMouseMotionListener( this );
 initRecs();
 }
 private void initRecs(){
 rec = new Rectangle[ 8 ];
 for ( int i = 0 ;i < rec.length;i ++ ){
 rec[i] = new Rectangle();
 }
 }
 public void paintComponent(Graphics g){
 g.drawImage(bi, 0 , 0 ,width,height, this );
 g.setColor(Color.RED);
 g.drawLine(startX,startY,endX,startY);
 g.drawLine(startX,endY,endX,endY);
 g.drawLine(startX,startY,startX,endY);
 g.drawLine(endX,startY,endX,endY);
 int x = startX < endX ? startX:endX;
 int y = startY < endY ? startY:endY;
 select = new Rectangle(x,y,Math.abs(endX - startX),Math.abs(endY - startY));
 int x1 = (startX + endX) / 2 ;
 int y1 = (startY + endY) / 2 ;
 g.fillRect(x1 - 2 ,startY - 2 , 5 , 5 );
 g.fillRect(x1 - 2 ,endY - 2 , 5 , 5 );
 g.fillRect(startX - 2 ,y1 - 2 , 5 , 5 );
 g.fillRect(endX - 2 ,y1 - 2 , 5 , 5 );
 g.fillRect(startX - 2 ,startY - 2 , 5 , 5 );
 g.fillRect(startX - 2 ,endY - 2 , 5 , 5 );
 g.fillRect(endX - 2 ,startY - 2 , 5 , 5 );
 g.fillRect(endX - 2 ,endY - 2 , 5 , 5 );
 rec[ 0 ] = new Rectangle(x - 5 ,y - 5 , 10 , 10 );
 rec[ 1 ] = new Rectangle(x1 - 5 ,y - 5 , 10 , 10 );
 rec[ 2 ] = new Rectangle((startX > endX ? startX:endX) - 5 ,y - 5 , 10 , 10 );
 rec[ 3 ] = new Rectangle((startX > endX ? startX:endX) - 5 ,y1 - 5 , 10 , 10 );
 rec[ 4 ] = new Rectangle((startX > endX ? startX:endX) - 5 ,(startY > endY ? startY:endY) - 5 , 10 , 10 );
 rec[ 5 ] = new Rectangle(x1 - 5 ,(startY > endY ? startY:endY) - 5 , 10 , 10 );
 rec[ 6 ] = new Rectangle(x - 5 ,(startY > endY ? startY:endY) - 5 , 10 , 10 );
 rec[ 7 ] = new Rectangle(x - 5 ,y1 - 5 , 10 , 10 );
 if (showTip){
 g.setColor(Color.CYAN);
 g.fillRect(p.x,p.y, 170 , 20 );
 g.setColor(Color.RED);
 g.drawRect(p.x,p.y, 170 , 20 );
 g.setColor(Color.BLACK);
 g.drawString( " 请按住鼠标左键不放选择截图区 " ,p.x,p.y + 15 );
 }
 }
 // 根据东南西北等八个方向决定选中的要修改的X和Y的座标
 private void initSelect(States state){
 switch (state){
 case DEFAULT:
 currentX = 0 ;
 currentY = 0 ;
 break ;
 case EAST:
 currentX = (endX > startX ? END_X:START_X);
 currentY = 0 ;
 break ;
 case WEST:
 currentX = (endX > startX ? START_X:END_X);
 currentY = 0 ;
 break ;
 case NORTH:
 currentX = 0 ;
 currentY = (startY > endY ? END_Y:START_Y);
 break ;
 case SOUTH:
 currentX = 0 ;
 currentY = (startY > endY ? START_Y:END_Y);
 break ;
 case NORTH_EAST:
 currentY = (startY > endY ? END_Y:START_Y);
 currentX = (endX > startX ? END_X:START_X);
 break ;
 case NORTH_WEST:
 currentY = (startY > endY ? END_Y:START_Y);
 currentX = (endX > startX ? START_X:END_X);
 break ;
 case SOUTH_EAST:
 currentY = (startY > endY ? START_Y:END_Y);
 currentX = (endX > startX ? END_X:START_X);
 break ;
 case SOUTH_WEST:
 currentY = (startY > endY ? START_Y:END_Y);
 currentX = (endX > startX ? START_X:END_X);
 break ;
 default :
 currentX = 0 ;
 currentY = 0 ;
 break ;
 }
 }
 public void mouseMoved(MouseEvent me){
 doMouseMoved(me);
 initSelect(current);
 if (showTip){
 p = me.getPoint();
 repaint();
 }
 }
 // 特意定义一个方法处理鼠标移动,是为了每次都能初始化一下所要选择的地区
 private void doMouseMoved(MouseEvent me){
 if (select.contains(me.getPoint())){
 this .setCursor( new Cursor(Cursor.MOVE_CURSOR));
 current = States.MOVE;
 } else {
 States[] st = States.values();
 for ( int i = 0 ;i < rec.length;i ++ ){
 if (rec[i].contains(me.getPoint())){
 current = st[i];
 this .setCursor(st[i].getCursor());
 return ;
 }
 }
 this .setCursor(cs);
 current = States.DEFAULT;
 }
 }
 public void mouseExited(MouseEvent me){

 }
 public void mouseEntered(MouseEvent me){

 }
 public void mouseDragged(MouseEvent me){
 int x = me.getX();
 int y = me.getY();
 if (current == States.MOVE){
 startX += (x - tempX);
 startY += (y - tempY);
 endX += (x - tempX);
 endY += (y - tempY);
 tempX = x;
 tempY = y;
 } else if (current == States.EAST || current == States.WEST){
 if (currentX == START_X){
 startX += (x - tempX);
 tempX = x;
 } else {
 endX += (x - tempX);
 tempX = x;
 }
 } else if (current == States.NORTH || current == States.SOUTH){
 if (currentY == START_Y){
 startY += (y - tempY);
 tempY = y;
 } else {
 endY += (y - tempY);
 tempY = y;
 }
 } else if (current == States.NORTH_EAST || current == States.NORTH_EAST ||
 current == States.SOUTH_EAST || current == States.SOUTH_WEST){
 if (currentY == START_Y){
 startY += (y - tempY);
 tempY = y;
 } else {
 endY += (y - tempY);
 tempY = y;
 }
 if (currentX == START_X){
 startX += (x - tempX);
 tempX = x;
 } else {
 endX += (x - tempX);
 tempX = x;
 }

 } else {
 startX = tempX;
 startY = tempY;
 endX = me.getX();
 endY = me.getY();
 }
 this .repaint();
 }
 public void mousePressed(MouseEvent me){
 showTip = false ;
 tempX = me.getX();
 tempY = me.getY();
 }
 public void mouseReleased(MouseEvent me){
 if (me.isPopupTrigger()){
 if (current == States.MOVE){
 showTip = true ;
 p = me.getPoint();
 startX = 0 ;
 startY = 0 ;
 endX = 0 ;
 endY = 0 ;
 repaint();
 } else {
 jf.dispose();
 updates();
 }

 }
 }
 public void mouseClicked(MouseEvent me){
 if (me.getClickCount() == 2 ){
 // Rectangle rec=new Rectangle(startX,startY,Math.abs(endX-startX),Math.abs(endY-startY));
 Point p = me.getPoint();
 if (select.contains(p)){
 if (select.x + select.width < this .getWidth() && select.y + select.height < this .getHeight()){
 get = bi.getSubimage(select.x,select.y,select.width,select.height);
 jf.dispose();
 updates();
 } else {
 int wid = select.width,het = select.height;
 if (select.x + select.width >= this .getWidth()){
 wid = this .getWidth() - select.x;
 }
 if (select.y + select.height >= this .getHeight()){
 het = this .getHeight() - select.y;
 }
 get = bi.getSubimage(select.x,select.y,wid,het);
 jf.dispose();
 updates();
 }

 }
 }
 }
 }

 public static void main(String args[]){
 SwingUtilities.invokeLater( new Runnable(){
 public void run(){
 new CaptureScreen();
 }
 });
 }
}
// 一些表示状态的枚举
enum States{
 NORTH_WEST( new Cursor(Cursor.NW_RESIZE_CURSOR)), // 表示西北角
 NORTH( new Cursor(Cursor.N_RESIZE_CURSOR)),
 NORTH_EAST( new Cursor(Cursor.NE_RESIZE_CURSOR)),
 EAST( new Cursor(Cursor.E_RESIZE_CURSOR)),
 SOUTH_EAST( new Cursor(Cursor.SE_RESIZE_CURSOR)),
 SOUTH( new Cursor(Cursor.S_RESIZE_CURSOR)),
 SOUTH_WEST( new Cursor(Cursor.SW_RESIZE_CURSOR)),
 WEST( new Cursor(Cursor.W_RESIZE_CURSOR)),
 MOVE( new Cursor(Cursor.MOVE_CURSOR)),
 DEFAULT( new Cursor(Cursor.DEFAULT_CURSOR));
 private Cursor cs;
 States(Cursor cs){
 this .cs = cs;
 }
 public Cursor getCursor(){
 return cs;
 }
}

原文： http://www.blogjava.net/hadeslee/archive/2007/09/04/142542.html