如何把awt或者swing的UI生成一个图形文件

 

package demo;

import java.io.File;
import org.jfree.chart.JFreeChart;
import java.io.IOException;
import java.io.OutputStream;
import java.io.BufferedOutputStream;
import java.io.FileOutputStream;
import java.awt.image.BufferedImage;
import org.jfree.chart.encoders.ImageFormat;
import java.awt.Graphics2D;
import java.awt.*;
import java.awt.*;
import org.jfree.chart.encoders.ImageEncoder;
import org.jfree.chart.encoders.ImageEncoderFactory;
import javax.swing.JFrame;
import javax.imageio.ImageIO;

public class ToImg {
  public ToImg() {
  }


  /** *//**
   * Saves a chart to a file in JPEG format.
   *
   * @param file  the file (<code>null</code> not permitted).
   * @param quality  the JPEG quality setting.
   * @param chart  the chart (<code>null</code> not permitted).
   * @param width  the image width.
   * @param height  the image height.
   *
   * @throws IOException if there are any I/O errors.
   */
  public static void saveChartAsJPEG(File file,
                                     float quality,
                                     JFreeChart chart,
                                     int width,
                                     int height) throws IOException {

    if (file == null) {
        throw new IllegalArgumentException("Null 'file' argument.");
    }
    if (chart == null) {
        throw new IllegalArgumentException("Null 'chart' argument.");
    }
    OutputStream out = new BufferedOutputStream(new FileOutputStream(file));

    BufferedImage images = chart.createBufferedImage(width, height, null);
    BufferedImage image = new BufferedImage(width, height, BufferedImage.TYPE_INT_RGB);
    Graphics2D g2 = image.createGraphics();
//    draw(g2, new Rectangle2D.Double(0, 0, width, height), null, info);
    g2.dispose();

    writeBufferedImage(image, ImageFormat.JPEG, out, quality);
    out.close();
  }

  public static void writeBufferedImage(BufferedImage image, String format,
      OutputStream outputStream, float quality)
      throws IOException {
    ImageEncoder imageEncoder
        = ImageEncoderFactory.newInstance(format, quality);
    imageEncoder.encode(image, outputStream);

  }

  public static void main(String[] args) {
    Robot robot = null;
    try {
      
      JFrame f = new Frame1(); 
      f.setSize(500,600);
      f.setVisible(true);
      f.setDefaultCloseOperation(2);
      BufferedImage image = new BufferedImage(500, 600, BufferedImage.TYPE_INT_RGB);
      f.getContentPane().paint(image.getGraphics());
      FileOutputStream out = new FileOutputStream("d:\\b.jpg");
      ImageIO.write(image, "jpeg" , out);
      out.close();

/** *//**    
     抓图  
      Robot robot = new java.awt.Robot();
      BufferedImage image = robot.createScreenCapture(new Rectangle(100, 100));
      ImageEncoder imageEncoder
          = ImageEncoderFactory.newInstance(ImageFormat.JPEG, 100);
      FileOutputStream out = new FileOutputStream("d:\\a.jpg");
      imageEncoder.encode(taget, out);
 }*/

   }
    catch (Exception ex) {
      ex.printStackTrace();
    }

  }

}