public void solve(int I, int J)
	{
		if (!STOP)
		{
			//terminating condition
			if (J == 9)
			{
				I++;
				J = 0;
				if (I == 9)
				{
					if (main.numSolutions < 999)
					{
						main.numSolutions++;
						main.numSolutionsLabel.setText("# of Solutions: "+(main.numSolutions+1));
						
						for (int i = 0; i < 9; i++)
							for (int j = 0; j < 9; j++)
								main.solutionBoard[main.numSolutions][9*i+j] = board[i][j]; //store solution info to be displayed later
					}
					else
					{
						main.numSolutions++;
						main.numSolutionsLabel.setText("# of Solutions: "+(main.numSolutions+1));
					}
					return;
				}
			}
			
			if (board[I][J] == -1) //empty space
			{
				int testVal = 1;
				
				while (testVal < 10)//find value to pass in
				{				
					board[I][J] = testVal;
					if (main.watchBox.getState())
						main.field[I][J].setText(" "+testVal);
					if (isValid())
						solve(I,J+1); //try to solve with this value
					
					testVal++;			//try a different value		
				}
				
				board[I][J] = -1;
				if (main.watchBox.getState())
					main.field[I][J].setText("");
				
				return;
			}
			else 
				solve(I,J+1); //go to next empty square
		}
	}