How To Take A BufferedImage From JEditorPane?

I need to load a URL into a JEditorPane, then take a BufferedImge from the JEditorPane, my code below will get me a blank/black image :

import java.awt.*;
import java.awt.image.*;
import javax.imageio.*;
import javax.swing.JEditorPane;
import javax.swing.JFrame;
import javax.swing.text.html.*;
import java.io.*;

public class Html_Browser
{
  public static void main(String[] args)
  {
    Dimension screenSize=Toolkit.getDefaultToolkit().getScreenSize();
    JEditorPane editorPane=new JEditorPane();
    editorPane.setEditorKit(new HTMLEditorKit());
    editorPane.setEditable(false);

    try
    {
      editorPane.setPage("https://news.yahoo.com/");
      Thread.sleep(3000);
      BufferedImage saveimg=new BufferedImage((int)screenSize.getWidth(),(int)screenSize.getHeight()-36,BufferedImage.TYPE_INT_RGB);
      Graphics2D g2=saveimg.createGraphics();
      editorPane.paint(g2); 
      ImageIO.write(saveimg,"png",new File("test.png"));
    }
    catch (Exception e)
    {
      editorPane.setContentType("text/html");
      editorPane.setText("<html>Connection issues!</html>");
    }
    
    JFrame frame=new JFrame();
    frame.getContentPane().add(editorPane);
    frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
    frame.setBounds(0,0,(int)screenSize.getWidth(),(int)screenSize.getHeight()-36);
    frame.setLocationRelativeTo(null);
    frame.setVisible(true);
  }
}

I added a 3-second delay, but it didn't work, what's the right way to do it ?

Solution

You might be able to use this approach.

It modifies the editor pane to read all the files synchronously. Then a PropertyChanngeEvent is generated when the I/O is finished.

import java.awt.*;
import java.awt.event.*;
import java.beans.*;
import java.io.*;
import java.net.*;
import javax.swing.*;
import javax.swing.text.*;
import javax.swing.text.html.*;
import java.awt.image.*;

public class EditorPaneLoadSynchronously extends JFrame
    implements ActionListener, PropertyChangeListener
{
    private JEditorPane html;
    private JTextField webURL;

    public EditorPaneLoadSynchronously()
    {
        JPanel urlPanel = new JPanel();
        getContentPane().add(urlPanel, BorderLayout.NORTH);

        webURL = new JTextField("https://stackoverflow.com", 15);
        webURL.addActionListener(this);
        urlPanel.add(webURL);

        JButton gotoURL = new JButton("Goto URL");
        gotoURL.addActionListener(this);
        urlPanel.add(gotoURL);

        HTMLEditorKit editorKit = new HTMLEditorKit()
        {
            private final ViewFactory factory = new HTMLFactory()
            {
                public View create(Element elem)
                {
                    View v = super.create(elem);

                    if ((v != null) && (v instanceof ImageView))
                    {
                        ((ImageView)v).setLoadsSynchronously( true );
                    }

                    return v;
                }
            };

            public ViewFactory getViewFactory()
            {
                return factory;
            }
        };

        html = new JEditorPane();
//      html.setEditorKit( editorKit );
//      html.setEditable( false );
        html.addPropertyChangeListener("page", this);

        JScrollPane scrollPane = new JScrollPane(html);
        scrollPane.setPreferredSize( new Dimension(400, 400) );
        getContentPane().add(scrollPane);
    }

    public void actionPerformed(ActionEvent e)
    {
        try
        {
//          html.setDocument( new HTMLDocument() );
            html.setPage( new URL(webURL.getText()) );
            System.out.println("After setPage");
        }
        catch(Exception exc)
        {
            System.out.println(exc);
        }
    }

    public void propertyChange(PropertyChangeEvent e)
    {
        try
        {
            System.out.println("Page Loaded");
//          BufferedImage bi = ScreenImage.createImage(html);
//          ScreenImage.writeImage(bi, "sync.jpg");
        }
        catch(Exception ee) {}
    }

    private static void createAndShowGUI()
    {
        EditorPaneLoadSynchronously frame = new EditorPaneLoadSynchronously();
        frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
        frame.pack();
        frame.setLocationByPlatform( true );
        frame.setVisible( true );

        frame.actionPerformed(null);
    }

    public static void main(String[] args) throws Exception
    {
        java.awt.EventQueue.invokeLater( () -> createAndShowGUI() );
    }
}

Note: the above code uses the Screen Image convenience class. You can replace it with your only code to create and write the BufferedImage.