How to use

addDocumentListener

method

in

javax.swing.text.DefaultStyledDocument

doc.addDocumentListener(new DocumentListener() {
  public void insertUpdate(DocumentEvent documentEvent) {
    documentChangedSinceLastRepaint = true;
undoManager.addPropertyChangeListener(redoAction);
doc.addDocumentListener(undoAction);
doc.addDocumentListener(redoAction);

public void startIt()
{
  m_document.addDocumentListener(this);
  m_forceRefresh=true;
  synchronized(m_mutex)
   {
    m_mutex.notify();
   }
}

public void setDocument(DefaultStyledDocument doc)
{
  try
  {
 // System.out.println(this.getClass().getName() + " - setDocument(" + doc + ")");
 m_document.removeDocumentListener(this);
 m_document = doc;
 m_tune = m_parser.parse(doc.getText(0, doc.getLength()));
 m_document.addDocumentListener(this);
 }
 catch (Exception e)
 { e.printStackTrace();
 }
}

undoManager.addPropertyChangeListener(redoAction);
doc.addDocumentListener(undoAction);
doc.addDocumentListener(redoAction);

undoManager.addPropertyChangeListener(redoAction);
doc.addDocumentListener(undoAction);
doc.addDocumentListener(redoAction);

undoManager.addPropertyChangeListener(redoAction);
doc.addDocumentListener(undoAction);
doc.addDocumentListener(redoAction);

doc.addDocumentListener(listener);

doc.addDocumentListener(new DocumentListener() {
  public void insertUpdate(DocumentEvent documentEvent) {
    documentChangedSinceLastRepaint = true;
undoManager.addPropertyChangeListener(redoAction);
doc.addDocumentListener(undoAction);
doc.addDocumentListener(redoAction);

doc.addDocumentListener(new DocumentListener() {
  public void insertUpdate(DocumentEvent documentEvent) {
    documentChangedSinceLastRepaint = true;
undoManager.addPropertyChangeListener(redoAction);
doc.addDocumentListener(undoAction);
doc.addDocumentListener(redoAction);

add(b, BorderLayout.CENTER);
doc.addDocumentListener(new DocumentListener() {
  public void insertUpdate(DocumentEvent documentEvent) {
    listen();

add(b, BorderLayout.CENTER);
doc.addDocumentListener(new DocumentListener() {
  public void insertUpdate(DocumentEvent documentEvent) {
    listen();

/**
 * @param listener The document listener for detecting changes to the content
 * @param rows     The number of rows (normally 6)
 * @param columns  The number of columns (normally 60)
 *
 * @return A new read only length limited text field with default theme
 */
public static JTextArea newReadOnlyLengthLimitedTextArea(DocumentListener listener, int rows, int columns) {
 JTextArea textArea = newReadOnlyTextArea(rows, columns);
 // Limit the length of the underlying document
 DefaultStyledDocument doc = new DefaultStyledDocument();
 doc.setDocumentFilter(new DocumentMaxLengthFilter(rows * columns));
 textArea.setDocument(doc);
 // Ensure we monitor changes
 doc.addDocumentListener(listener);
 return textArea;
}

expressionTextDoc.addDocumentListener(new DocumentListener() {
  public void insertUpdate(DocumentEvent documentEvent) {
    listen();

doc = new DefaultStyledDocument();
doc.setDocumentFilter(new DocumentSizeFilter(500));
doc.addDocumentListener(new DocumentListener(){
  @Override
  public void changedUpdate(DocumentEvent e) { updateCount();}