Problem with DocumentListener

I posted this to the nbuser mailing list, but this is probably a better place to get a response.

I am a complete newbie to Java (after many years with Visual C++), and am writing my first project. I have hit a brick wall in NetBeans 5.5 trying to implement a DocumentListener. I noticed that even though I imported java.awt.* I also had to import java.awt.event.* to implement EventListener. So I have imported javax.swing.event.*, but NetBeans still cannot find DocumentListener. I get a "cannot find symbol" error, and the location is given as class javax.swing.JTextField.

These are the relevant bits of code:

import javax.swing.*;

import java.awt.*;

import java.awt.event.*;

import java.io.*;

import javax.swing.event.*;

-

TopLevelListener tldl =new TopLevelListener();

-

topLevel =new JTextField(32);

topLevel.setMaximumSize(new Dimension(300, 25));

*topLevel.addDocumentListener(tldl);

--

*privateclass TopLevelListenerimplements DocumentListener

{

publicvoid insertUpdate(DocumentEvent e)

{

<some code>

}

}

I get error flags on the lines prefixed with *

Thanks for any help.

[1770 byte] By [JeffG1a] at [2007-11-27 2:01:40]