java 复制图像

import java.awt.Color; import java.awt.Graphics; import java.awt.Image; import java.awt.event.MouseEvent; import java.awt.event.MouseListener; import java.awt.event.MouseMotionListener; import javax.swing.ImageIcon; import javax.swing.JFrame; import javax.swing.JPanel; public class CopyArea { JFrame frame; public CopyArea(){ frame=new JFrame(); frame.setSize(500, 500); frame.add(new DrawPanel()); frame.setVisible(true); } public static void main(String arg[]){ new CopyArea(); } } class DrawPanel extends JPanel implements MouseListener,MouseMotionListener { int x1; int y1; int x2; int y2; int xx1; int yy1; int xx2; int yy2; Color color; int sign=0; public DrawPanel() { setBackground(Color.white); addMouseListener(this); addMouseMotionListener(this); } public void mousePressed(MouseEvent e) { if(sign==0){ x1=e.getX(); y1=e.getY(); } else{ xx1=e.getX(); yy1=e.getY(); } } public void paintComponent(Graphics g){ super.paintComponent(g); g.setColor(Color.black); ImageIcon imageIcon = new ImageIcon("pic.jpg"); Image im = imageIcon.getImage(); g.drawImage(im, 0, 0, this); } public void mouseReleased(MouseEvent e) {if(sign==0){ x2=e.getX(); y2=e.getY(); sign=(sign+1)%2; } else{ xx2=e.getX(); yy2=e.getY(); Graphics g=this.getGraphics(); g.copyArea(Math.min(x1, x2), Math.min(y1, y2), Math.max(x1, x2)-Math.min(x1, x2), Math.max(y1, y2)-Math.min(y1, y2), xx1-x1, yy1-y1); // System.out.println("("+x1+","+y1+")"+"("+x2+","+y2+")"+"("+xx1+","+yy1+")"); sign=(sign+1)%2; } } public void mouseClicked(MouseEvent e) {} public void mouseEntered(MouseEvent e) {} public void mouseExited(MouseEvent e) {} public void mouseDragged(MouseEvent e) {} public void mouseMoved(MouseEvent e) {} }