diff -r e70a0e3555fb -r 576e7a2861ae src/de/uapcore/sudoku/SudokuTextField.java
--- a/src/de/uapcore/sudoku/SudokuTextField.java	Fri Feb 01 10:18:47 2013 +0100
+++ /dev/null	Thu Jan 01 00:00:00 1970 +0000
@@ -1,138 +0,0 @@
-/*
- * Copyright 2013 Mike Becker. All rights reserved.
- * 
- * Redistribution and use in source and binary forms, with or without
- * modification, are permitted provided that the following conditions are met:
- * 
- * 1. Redistributions of source code must retain the above copyright
- *    notice, this list of conditions and the following disclaimer.
- * 
- * 2. Redistributions in binary form must reproduce the above copyright
- *    notice, this list of conditions and the following disclaimer in the
- *    documentation and/or other materials provided with the distribution.
- * 
- * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
- * AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
- * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
- * ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDER OR CONTRIBUTORS BE
- * LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
- * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
- * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
- * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
- * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
- * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
- * POSSIBILITY OF SUCH DAMAGE.
- */
-
-package de.uapcore.sudoku;
-
-import java.awt.Color;
-import java.awt.Dimension;
-import java.awt.Font;
-import java.awt.event.FocusAdapter;
-import java.awt.event.FocusEvent;
-import java.awt.event.KeyAdapter;
-import java.awt.event.KeyEvent;
-import javax.swing.JTextField;
-
-/**
- *
- * @author mike
- */
-public final class SudokuTextField extends JTextField {
-    
-    private boolean modified;
-    
-    public SudokuTextField() {
-        setBorder(null);
-        setBackground(Color.WHITE);
-        
-        setFont(new Font("Dialog", Font.PLAIN, 18));
-        setHorizontalAlignment(JTextField.CENTER);
-        
-        Dimension dim = new Dimension(40,40);
-        setPreferredSize(dim);
-        setMinimumSize(dim);
-        setMaximumSize(dim);
-        
-        addKeyListener(new KeyAdapter() {
-            private void handle(KeyEvent e) {
-                char c = e.getKeyChar();
-                if (!e.isAltDown() && !e.isControlDown() &&
-                        !Character.isISOControl(c)) {
-                    // Perform clean input check
-                    if (getText().length() > 0 && getSelectedText() == null) {
-                        if (c != KeyEvent.CHAR_UNDEFINED) {
-                            e.consume();
-                        }
-                    } else {
-                        if (c < '1' || c > '9') {
-                            e.consume();
-                        } else {
-                            setModified(true);
-                        }
-                    }
-                } else {
-                    // We can still be tricked by hotkeys, so do it the hard way
-                    if (!getText().matches("^[1-9]$")) {
-                        setText("");
-                    }
-                }
-            }
-            
-            @Override
-            public void keyPressed(KeyEvent e) {
-                handle(e);
-            }
-
-            @Override
-            public void keyTyped(KeyEvent e) {
-                handle(e);
-            }
-
-            @Override
-            public void keyReleased(KeyEvent e) {
-                handle(e);
-            }
-            
-        });
-        addFocusListener(new FocusAdapter() {
-            @Override
-            public void focusGained(FocusEvent e) {
-                selectAll();
-            }
-            @Override
-            public void focusLost(FocusEvent e) {
-                select(0, 0);
-            }
-        });
-    }
-    
-    public int getValue() {
-        if (getText().length() > 0) {
-            return Integer.valueOf(getText());
-        } else {
-            return 0;
-        }
-    }
-    
-    public void setValue(int v) {
-        if (v == 0) {
-            setText("");
-        } else if (v < 10) {
-            setText(String.valueOf(v));
-        } else {
-            throw new IllegalArgumentException(
-                    "Sudoku numbers must be in range 0-9 (0 means 'not set')");
-        }
-    }
-    
-    public void setModified(boolean modified) {
-        this.modified = modified;
-        setForeground(modified?Color.BLUE:Color.BLACK);
-    }
-    
-    public boolean isModified() {
-        return modified;
-    }
-}