^_^y

以下範例示範如何將JPanel的畫面輸出成JPEG

import java.awt.image.BufferedImage;
import java.io.BufferedOutputStream;
import java.io.FileOutputStream;

import javax.swing.JButton;
import javax.swing.JFrame;
import javax.swing.JLabel;
import javax.swing.JPanel;

import com.sun.image.codec.jpeg.JPEGCodec;
import com.sun.image.codec.jpeg.JPEGEncodeParam;
import com.sun.image.codec.jpeg.JPEGImageEncoder;

public class JPanel2JPG {
 public static void main(String[] args) throws Exception {
  new JPanel2JPG().createAndShowGUI();
 }
 
 public void createAndShowGUI() throws Exception
 {
  JFrame frame = new JFrame();
  JPanel panel = new JPanel();
  frame.getContentPane().add(panel);
  
  JButton button = new JButton("將此畫面輸出");
  JLabel label = new JLabel("Hello World");
  panel.add(button);
  panel.add(label);
  
  frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
  frame.setSize(400,300);
  frame.setVisible(true);
  
  // 將畫面輸出成圖片
  BufferedImage bufferedImage = (BufferedImage) panel.createImage(
   panel.getWidth(), panel.getHeight());
  panel.paint(bufferedImage.getGraphics());
  
  // 設定檔案輸入目錄
  BufferedOutputStream out = new BufferedOutputStream(new FileOutputStream("c:/jpanel.jpg"));
  JPEGImageEncoder imageEncoder = JPEGCodec.createJPEGEncoder(out);
  JPEGEncodeParam encodeParam = 
   imageEncoder.getDefaultJPEGEncodeParam(bufferedImage);
  encodeParam.setQuality(1.0f, false);
  imageEncoder.encode(bufferedImage);
  out.flush();
  out.close();
 }
}