Access off screen data

Question

Does anyone know if it is possible to do the following in Java (It is step 2 that I need help with):
1) Load any third party application e.g Firefox
This will display part of a web page and the rest will only be made visible by using the scrollbar.
2) I want to access the text/images in the whole of the web page without using the scroll bar. e.g access off screen data and save it to something like a BufferedImage.(I guess it is similar to a screenshot but of data that is not currently visible on the screen).
I need this to be generic enough to work for any application that uses scroll bars.
Thanks

Answer 1

1. Use Runtime.getRuntime().exec( <command> ) to run another program.
2. You can use ImageIO.read( <url> ) to read images and return a BufferedImage from the internet.
You can give this program I made a test drive as it shows how to run a separate process and load an image from the internet:
/* DynamicClasses.java
* @author scphan
* created: 12, May 2009
* tested successfully with jdk1.6.0_11
import java.lang.ref.*;
import java.util.*;
import javax.tools.*;
import java.io.*;
public class DynamicClasses
     public static void main( String args[] )
          DynamicClasses obj = new DynamicClasses();
          obj.compileAndRun( new File( "CompileTest.java" ) );
     public void compileAndRun( final File file )
          JavaCompiler compiler = ToolProvider.getSystemJavaCompiler();
          StandardJavaFileManager filemanager = compiler.getStandardFileManager( null, null, null );
          System.out.println( "Default Compiler: " + compiler.getClass().getName() + "  toString(): " + compiler );
          try
               deleteClassFile( file );
               try
                    Thread.sleep( 5000 );
               catch ( InterruptedException e )
                    e.printStackTrace();
               Iterable compilationUnits = filemanager.getJavaFileObjects( file );
               compiler.getTask( null, filemanager, null, null, null, compilationUnits ).call();
               filemanager.close();
               run( file.getName().replaceAll(".java","") );
          catch ( IOException e )
               e.printStackTrace();
     public void run( final String filenameNoExt )
          throws IOException
          Process proc = Runtime.getRuntime().exec( String.format( "java %s", filenameNoExt ) );
     private void deleteClassFile( File file )
          String fNameNoExt = file.getName().replaceAll( ".java", "" );
          File xFile = new File( fNameNoExt+".class" );
               if ( xFile.exists() )
                    xFile.delete();
/* CompileTest.java
* @author scphan
* created: 12, May 2009
* tested successfully with jdk1.6.0_11
import java.awt.*;
import java.awt.image.BufferedImage;
import javax.swing.*;
import java.net.URL;
import java.io.IOException;
import javax.imageio.ImageIO;
public class CompileTest
     private static final String IMAGE_URL = "http://konohaleaf.info/images/stories/cherry_tree.png";
     public static void main( String args[] )
          final JOptionPane pane = new JOptionPane();
          pane.showMessageDialog( null, "Greetings, compiling test successful!", "Compile Test Successful", JOptionPane.INFORMATION_MESSAGE );
          final JFrame f = new JFrame( "Compile Test Successful" );
          f.setDefaultCloseOperation( f.EXIT_ON_CLOSE );
          final JLabel label = new JLabel();
          final BufferedImage image = grabImage( CompileTest.IMAGE_URL );
          if ( image != null )
               label.setIcon( new ImageIcon(image) );
          else
               label.setText( "Image could not load, displaying alternative text instead..." );
          f.getContentPane().add( label );
          f.pack();
          f.setVisible( true );
     private static BufferedImage grabImage( String url )
          BufferedImage image = null;
          try
               image = ImageIO.read( new URL( url ) );
          catch ( IOException e )
               e.printStackTrace();
               return null;
          return image;
}[http://konohaleaf.info/index.php?option=com_content&view=article&id=71:programmatically-compile-and-execute-in-java&catid=50:misc-example-programs&Itemid=64]
Just parse through the html code for any <img src... ".jpg", ".png", etc. and store the paths which will then be used to read the images with javax.imageio.ImageIO.
Edited by: scphan on May 13, 2009 1:09 PM