How can i replace some string in a JTextaArea/JTex at current time!

Question

Hey guys, this problem is driving me crazy... i want to do a keyboard event.. like the emoticons in msn,
so, i want that when i type /land ("latex comand"), a character appears replacing the command in the JTextArea. I did it, but when i type
/happy, the character doesn�t appear! Just when i type space in keyboard...:/
Can anybody help me?
public class TelaParametro extends JDialog {
     private GerenciadorExterno gerInterface;
     private TelaLeis telaLeis;
     private int parametro;
     private Argument argumento;
     private String codigo;
     private String path = "images/";
     private TecladoVirtual tecl;
     private boolean DigitandoLatex;
     private String latex;
     /* atributo que serve para dizer se o usuario apertou no Ok ou no Cancel */
     private int flagModal;
       JPanel panel1 = new JPanel();
       JButton btnOK = new JButton();
       JButton btnCancel = new JButton();
       JTextArea tfEspec = new JTextArea();
       JScrollPane rolagem;
       JLabel labelEntrada = new JLabel();
       JButton btnDigitacao = new JButton();
       JButton btnTecladoVirtual = new JButton();
     JPanel panel2 = new JPanel();
     BorderLayout borderLayout1 = new BorderLayout();
     BorderLayout borderLayout2 = new BorderLayout();
     JPanel panel3 = new JPanel();
     GridLayout gridLayout1 = new GridLayout();
     JPanel panel4 = new JPanel();
     BorderLayout borderLayout3 = new BorderLayout();
     JPanel panel5 = new JPanel();
     JPanel panel6 = new JPanel();
     JPanel panel7 = new JPanel();
     JPanel panel8 = new JPanel();
public TelaParametro(TelaLeis telaLeis, GerenciadorExterno gerInterface) {
          super(telaLeis);
          try  {
               this.telaLeis = telaLeis;
               this.gerInterface = gerInterface;
               this.tecl = new TecladoVirtual(this);
               flagModal = 0;
               DigitandoLatex = false;
               jbInit();
          catch (Exception e) {
                 e.printStackTrace();
private void jbInit() throws Exception {
             this.setLocation(240,220);
//             this.setLocation((gerInterface.getTamanhoHorizontal()/2) - 160,(gerInterface.getTamanhoVertical()/2) - 80);
             this.setSize(320, 160);
             this.setTitle("Parametro");
             tfEspec.setFont(new Font ("CZT", Font.PLAIN, 12));
             tfEspec.setText("");
          rolagem = new JScrollPane(tfEspec);
          this.setModal( true );
          tfEspec.addKeyListener(new java.awt.event.KeyAdapter() {
               public void keyPressed(KeyEvent e) {
                    tfEspec_keyPressed(e);
          btnOK.setForeground(Color.green);
          btnOK.setFont(new Font("Dialog", 1, 12));
          btnOK.setLabel(this.retornarMensagem("COD0072"));
          btnOK.addActionListener(new java.awt.event.ActionListener() {
              public void actionPerformed(ActionEvent e) {
                    btnOK_actionPerformed(e);
          btnDigitacao.setFont(new Font("Dialog", 1, 12));
          btnDigitacao.setText("D");
          btnDigitacao.addActionListener(new java.awt.event.ActionListener() {
          public void actionPerformed(ActionEvent e) {
               btnTecladoVirtual_actionPerformed(e);
          ImageIcon teclicon = new ImageIcon(path + "teclado.gif");
          btnTecladoVirtual.setIcon(teclicon);
          btnTecladoVirtual.setToolTipText("TecladoVirtual");
          btnTecladoVirtual.addActionListener(new java.awt.event.ActionListener() {
          public void actionPerformed(ActionEvent e) {
               btnTecladoVirtual_actionPerformed(e);
          btnCancel.setForeground(Color.red);
          btnCancel.setFont(new Font("Dialog", 1, 12));
          btnCancel.setLabel(this.retornarMensagem("COD0078"));
          btnCancel.addActionListener(new java.awt.event.ActionListener() {
                 public void actionPerformed(ActionEvent e) {
                    btnCancel_actionPerformed(e);
          labelEntrada.setText("   Entre com tal parametro:");
          panel1.setLayout(borderLayout1);
          panel2.setLayout(borderLayout2);
          panel3.setLayout(gridLayout1);
          panel4.setLayout(borderLayout3);
          this.getContentPane().add(panel1, BorderLayout.CENTER);
          panel1.add(panel2, BorderLayout.CENTER);
          panel2.add(rolagem,  BorderLayout.CENTER);
          panel2.add(panel5, BorderLayout.WEST);
          panel2.add(panel6,  BorderLayout.SOUTH);
          panel2.add(panel7,  BorderLayout.EAST);
          panel2.add(panel8, BorderLayout.NORTH);
          panel1.add(panel3,  BorderLayout.SOUTH);
          panel3.add(btnOK, null);
          panel3.add(btnCancel, null);
          panel1.add(panel4, BorderLayout.NORTH);
          panel4.add(labelEntrada,  BorderLayout.CENTER);
          panel4.add(btnTecladoVirtual,  BorderLayout.EAST);
private void tfEspec_keyPressed(KeyEvent e){
         String str = tfEspec.getText() ;
         System.out.println("char "  + e.getKeyChar());
         System.out.println("texto " + str);
         str = str.replace("\\land", ZString.AND);
         //System.out.println("strReplaced " + str);
         tfEspec.setText(str);
         tfEspec.repaint();
}

Answer 1

But there is no method "addDocumentListener" for JTextArea =/ [url http://java.sun.com/docs/books/tutorial/uiswing/events/documentlistener.html]How to Write a Document Listener.