How to know whether any changes in the jtextarea have been made or not?

Question

I've created a jtextarea where a user can modify its content. I want to know,if there is any way, whether the user has modified its content or not before closing the application. Please help.
-Thanks in advance

Answer 1

You need to add a DocumentListener to the Document that backs the text area.

Then in the callback methods (insertUpdate(), removeUpdate(), changedUpdate()) of the listener, simply set a flag that something has changed and test that flag before closing the application

public class MyPanel
  implements DocumentListener
{
  private boolean changed;

  public MyPanel()
  {
    JTextArea textArea = new JTextArea();
    textArea.getDocument().addDocumentListener(this);
    .....
  }

  .....

  public void insertUpdate(DocumentEvent e)
  {
    changed = true;
  }
  public void removeUpdate(DocumentEvent e)
  {
    changed = true;
  }
  public void changedUpdate(DocumentEvent e)
  {
    changed = true;
  }
}