Keyboard - Character replacement - Keystroke Event !

Question

Hello ! I am developing a specialized editor using JEditorPane.
One the functionalities that I am trying to provide is character replacement using keyboard. Meaning that if some one enters, say, 'q' then a 'z' should be printed at the point of insertion. Something like
"This is a ebra"--> After typing 'q' on the keyboard before the beginning of the fourth word "ebra", the resulting text in the editor pane should look like "This is a zebra"; meaning here 'q' is used to type in 'z'.
Now here is my code but I am getting both 'z' and 'q' printed i.e. the result looks like, "This is a zebraq". So my questions are,
1) How do I get rid of the unwanted 'q'?
2) Is there a better way of doing this kind of replacement.
Thanks in advance!!
public void keyTyped (KeyEvent e)
PressedKey = e.getKeyChar();
String strBeforeInsert = new String("");
String strAfterInsert = new String("");
String docString = new String("");
try{
int length = edit.getDocument().getLength();
strBeforeInsert = edit.getDocument().getText(0,dot);
System.out.println("---- strBeforeInsert " + strBeforeInsert);
strAfterInsert = edit.getDocument().getText((dot), (length-dot));
System.out.println("---- strAfterInsert " + strAfterInsert);     
catch (BadLocationException ble){
if (PressedKey == 'q')
     System.out.println(">>>>>> " + PressedKey);
     docString = strBeforeInsert.concat("z") + strAfterInsert;
     edit.setText(docString);

Answer 1

I would use a DocumentListener. Check out the Swing tutorial for more information:
http://java.sun.com/docs/books/tutorial/uiswing/events/documentlistener.html
In the insertString(..) method when a 'q' is typed, insert a 'z' instead.