这篇文章主要讲解了“Java实现屏幕截图工具的代码怎么写”，文中的讲解内容简单清晰，易于学习与理解，下面请大家跟着小编的思路慢慢深入，一起来研究和学习“Java实现屏幕截图工具的代码怎么写”吧！
效果展示
程序运行后的截图：
先测试一下功能：
截图过程对界面的捕捉：
双击保存后的显示界面：
后续的步骤就自己去尝试吧，这里给出了简单的测试过程。
程序结构
核心代码
CaptureScreen.java类
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; 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 public CaptureScreen() { super("屏幕截取"); try{ UIManager.setLookAndFeel(UIManager.getSystemLookAndFeelClassName()); }catch(Exception exe){ exe.printStackTrace(); } initWindow(); initOther(); } private void initOther(){ jtp=new JTabbedPane(JTabbedPane.TOP,JTabbedPane.SCROLL_TAB_LAYOUT); } private void initWindow(){ start=new JButton("开始截取"); cancel=new JButton("退出"); start.addActionListener(this); cancel.addActionListener(this); JPanel buttonJP=new JPanel(); c=new JPanel(new BorderLayout()); JLabel jl=new JLabel("屏幕截取", JLabel.CENTER); jl.setFont(new Font("黑体",Font.BOLD,40)); jl.setForeground(Color.RED); c.add(jl,BorderLayout.CENTER); buttonJP.add(start); buttonJP.add(cancel); buttonJP.setBorder(BorderFactory.createTitledBorder("公共操作区")); JPanel jp=new JPanel();//放置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.EXIT_ON_CLOSE); } 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); // 调整LookAndFeel（javax.swing） } } 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(); // （通过本地操作）控制鼠标、键盘等实际输入源（java.awt） Toolkit tk=Toolkit.getDefaultToolkit(); // AWT组件的抽象父类（java.awt） 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); // 自定义的Temp类的对象 jf.getContentPane().add(temp,BorderLayout.CENTER); jf.setUndecorated(true); jf.setSize(di); jf.setVisible(true); jf.setAlwaysOnTop(true); } catch(Exception exe){ exe.printStackTrace(); } } 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){ if(!ext.endsWith(".jpg")){ String ns=ext+".jpg"; file=new File(ns); about="JPG"; } } else if(ff instanceof PNGfilter){ if(!ext.endsWith(".png")){ String ns=ext+".png"; file=new File(ns); about="PNG"; } }else if(ff instanceof BMPfilter){ if(!ext.endsWith(".bmp")){ String ns=ext+".bmp"; file=new File(ns); about="BMP"; } }else if(ff instanceof GIFfilter){ if(!ext.endsWith(".gif")){ String ns=ext+".gif"; file=new File(ns); about="GIF"; } } 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(); } } 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; } // java.awt.datatransfer（接口） Transferable trans = new Transferable(){ // 内部类 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){ // 金属外观 try{ UIManager.setLookAndFeel(UIManager.getCrossPlatformLookAndFeelClassName()); SwingUtilities.updateComponentTreeUI(this); }catch(Exception exe){ exe.printStackTrace(); } }else if(source==system){ // 本地外观 try{ UIManager.setLookAndFeel(UIManager.getSystemLookAndFeelClassName()); SwingUtilities.updateComponentTreeUI(this); }catch(Exception exe){ exe.printStackTrace(); } } } //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(); } 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)"; } } //一个临时类，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（十字线） 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,则提示就不再显示了 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); // current：当前状态（state） 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区域 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(); // 分别处理一系列的（光标）状态（枚举值） 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()){ // 右键 if(current==States.MOVE){ showTip=true; p=me.getPoint(); startX=0; startY=0; endX=0; endY=0; repaint(); } else{ // 普通情况 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; }}感谢各位的阅读，以上就是“Java实现屏幕截图工具的代码怎么写”的内容了，经过本文的学习后，相信大家对Java实现屏幕截图工具的代码怎么写这一问题有了更深刻的体会，具体使用情况还需要大家实践验证。这里是编程网，小编将为大家推送更多相关知识点的文章，欢迎关注！
