This is the GUI that I promised much too long ago. At this late date, it is completely optional whether you use it or not. If you would like to try it, here's how:

1. Download the file SudokuGui.java into the same directory as your Sudoku project.
   
   
2. Compile everything.
   
   
3. Run the program from the SudokuGui class (which contains a main method).
   

To use the program, either enter your own numbers into the GUI and click Solve, or use one of the three preprogrammed problem (Buttons 1, 2, and 3).

This program assumes you have a SudokuSolver class with a default constructor (one with no parameters) and a solve(int[][]) method. The single line in my program that uses your program is:

new SudokuSolver().solve(array);

If you have done the assignment correctly, this should work with your program.