java源代码

				// ImagePanel.java
				// ImagePanel contains an image for display.  The image is 
				// converted to a BufferedImage for filtering purposes.
				package com.deitel.advjhtp1.java2d;
				
				// Java core packages
				import java.awt.*;
				import java.awt.event.*;
				import java.awt.image.*;
				import java.net.*;
				
				 // Java extension packages
				import javax.swing.*;
				import javax.swing.event.*;
				
				public class ImagePanel extends JPanel {
				   
				   private BufferedImage displayImage; // filtered image
				   private BufferedImage originalImage; // original image copy
				   private Image image; // image to load
				   
				   // ImagePanel constructor
				   public ImagePanel( URL imageURL )
				   {
				      image = 
				         Toolkit.getDefaultToolkit().createImage( imageURL );          
				      
				      // create MediaTracker for image
				      MediaTracker mediaTracker = new MediaTracker( this );
				      mediaTracker.addImage( image, 0 );
				      
				      // wait for Image to load
				      try {
				         mediaTracker.waitForAll();
				      } 
				      
				      // exit program on error
				      catch( InterruptedException interruptedException ) {
				         interruptedException.printStackTrace();
				      }
				      
				      // create BufferedImage from Image 
				      originalImage = new BufferedImage( image.getWidth( null ), 
				         image.getHeight( null ), BufferedImage.TYPE_INT_RGB );
				      
				      //displayImage = new BufferedImage( image.getWidth( null ), 
				      //   image.getHeight( null ), BufferedImage.TYPE_INT_RGB );
				      
				      displayImage = originalImage; 
				      
				      // draw Image on Graphics2D object
				      Graphics2D graphics = displayImage.createGraphics();
				      graphics.drawImage( image, null, null );
				   
				   } // end ImagePanel constructor 
				   
				   // apply Java2DImageFilter to Image   
				   public void applyFilter( Java2DImageFilter filter )
				   {
				      // process Image using ImageFilter
				      displayImage = filter.processImage( displayImage );
				      repaint();
				   }   
				   
				   // set Image to originalImage 
				   public void displayOriginalImage() 
				   {
				      displayImage = new BufferedImage( image.getWidth( null ), 
				         image.getHeight( null ), BufferedImage.TYPE_INT_RGB );
				      
				      Graphics2D graphics = displayImage.createGraphics();
				      graphics.drawImage( originalImage, null, null );
				      repaint();
				   }
				  
				   // draw ImagePanel 
				   public void paintComponent( Graphics g )
				   {
				      super.paintComponent( g );
				      Graphics2D graphics = ( Graphics2D ) g;
				      graphics.drawImage( displayImage, 0, 0, null );
				   }
				
				   // get preferred ImagePanel size
				   public Dimension getPreferredSize()
				   {
				      return new Dimension( displayImage.getWidth(), 
				         displayImage.getHeight() );
				   }
				   
				   // get minimum ImagePanel size
				   public Dimension getMinimumSize()
				   {
				      return getPreferredSize();
				   }
				}
				
				/***************************************************************
				 * (C) Copyright 2002 by Deitel & Associates, Inc. and         *
				 * Prentice Hall. All Rights Reserved.                         *
				 *                                                             *
				 * DISCLAIMER: The authors and publisher of this book have     *
				 * used their best efforts in preparing the book. These        *
				 * efforts include the development, research, and testing of   *
				 * the theories and programs to determine their effectiveness. *
				 * The authors and publisher make no warranty of any kind,     *
				 * expressed or implied, with regard to these programs or to   *
				 * the documentation contained in these books. The authors     *
				 * and publisher shall not be liable in any event for          *
				 * incidental or consequential damages in connection with, or  *
				 * arising out of, the furnishing, performance, or use of      *
				 * these programs.                                             *
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