How to forbid the backspace in a JTextField?

Question

Hello,
I'm trying to write a JTextField KeyListener that basically consumes all backspaces, so that anything input by the user in the field cannot be cancelled. (The user doesn't setText()).
How can I do that? It seems like I cannot!
I've tried by identifying '\b' and consume the KeyEvent, but then the backspace is still executed.

Answer 1

Lolz, ok I'm not sure of the use case, but lets have some fun.
One way would be to set the DocumentFilter
                ((AbstractDocument)jtf.getDocument()).setDocumentFilter(new DocumentFilter(){
                    @Override
                    public void remove(FilterBypass fb, int offset, int length) throws BadLocationException {
                        //Won't remove
                        //new Exception("remove " + offset + "," + length).printStackTrace();
                    @Override
                    public void replace(FilterBypass fb, int offset, int length, String text, AttributeSet attrs)
                            throws BadLocationException {
                        if(offset == fb.getDocument().getLength()){
                            super.replace(fb, offset, length, text, attrs);
                });Just make sure that you remove the doc filter if you want to programmatically modify the value.
Edited by: Moot_Void on Mar 19, 2010 5:19 PM
Need to figure something out for replace too though.
Edited by: Moot_Void on Mar 19, 2010 5:34 PM
Added replace only allowed when the offset is at length of document.