Empty Stack Exception

Question

I have got the following code to display a web page in a JScrollPane. It displays fine but i keep getting an empty stack exception(displayed at end) can anyone help?
package ACT;
import java.io.*;
import java.net.*;
import java.awt.*;
import java.awt.event.*;
import javax.swing.*;
import javax.swing.event.*;
import javax.swing.text.html.*;
public class Locate extends JEditorPane implements HyperlinkListener
private JEditorPane paneReference;
private static JScrollPane displayHolder;
public Locate(String URLString) throws IOException
super(URLString);
paneReference = this;
paneReference.setEditable(false);
displayHolder = new JScrollPane(paneReference);
displayHolder.setPreferredSize(new Dimension(740,465));
public void hyperlinkUpdate(HyperlinkEvent e)
try
if ( e.getEventType() == HyperlinkEvent.EventType.ACTIVATED )
paneReference.setPage(e.getURL());
catch (Exception ex)
ex.printStackTrace(System.err);
public JScrollPane getMap()
return displayHolder;
Error:
java.util.EmptyStackException
at java.util.Stack.peek(Stack.java:82)
at javax.swing.text.DefaultStyledDocument$ElementBuffer.insertElement(DefaultStyledDocument.java:1623)
at javax.swing.text.DefaultStyledDocument$ElementBuffer.insertUpdate(DefaultStyledDocument.java:1361)
at javax.swing.text.DefaultStyledDocument$ElementBuffer.insert(DefaultStyledDocument.java:1231)
at javax.swing.text.DefaultStyledDocument.insert(DefaultStyledDocument.java:194)
at javax.swing.text.html.HTMLDocument.insert(HTMLDocument.java:212)
at javax.swing.text.html.HTMLDocument$HTMLReader.flushBuffer(HTMLDocument.java:3014)
at javax.swing.text.html.HTMLDocument$HTMLReader.flush(HTMLDocument.java:1921)
at javax.swing.text.html.HTMLEditorKit.read(HTMLEditorKit.java:240)
at javax.swing.JEditorPane.read(JEditorPane.java:421)
at javax.swing.JEditorPane$PageLoader.run(JEditorPane.java:468)

Answer 1

Is the HTML of the webpage well-formed?