I'm having an issue with a mock game of Tic tac toe. I'm using a two-dimensional array to represent the playing board, and have instantiated it as follows. It's required that I use a char type array. I realize that I shouldn't have to specify that each index is null, as that's the default for char, but I thought I would give it a try.
public TicTacToe2D()
{
board = new char[3][3];
for(int i = 0; i < board.length; i++)
{
for(int j = 0; j < board[i].length; j++)
{
board[j] = null;
}
board[i] = null;
}
}
Here I'm checking for a win condition, seeing if indexes are equal to each other and not null (the default) though I have attempted using ' ' for my array initial value. In that case I got the error: "incompatible types: char cannot be converted to char[]"
public char isWin()
{
//Check for row wins
if (board[0][0] == board[0][1] && board[0][1] == board[0][2] && board[0][0] != null)
return true;
if (board[1][0]==board[1][1] && board[1][1]==board[1][2] && board[1][0] != null)
return true;
if (board[2][0]==board[2][1] && board[2][1]==board[2][2] && board[2][0] != null)
return true;
//Check for column wins
if (board[0][0]==board[1][0] && board[1][0]==board[2][0] && board[0][0] != null)
return true;
if (board[0][1]==board[1][1] && board[1][1]==board[2][1] && board[0][1] != null)
return true;
if (board[0][2]==board[1][2] && board[1][2]==board[2][2] && board[0][2] != null)
return true;
//Check for diagonal wins
if (board[0][0]==board[1][1] && board[1][1]==board[2][2] && board[0][0] != null)
return true;
if (board[2][0] == board[1][1] && board[1][1] == board[0][2] && board[2][0] != 0)
return true;
else return false;
}
When checking if an index is null I get the error "incomparable types: char and " Any help would be greatly appreciated!
The datatype char is primitive, so it can't be null. But the default value is the null character, \0 (or \u0000). JLS Section 4.12.5 gives default values:
- For type char, the default value is the null character, that is, '\u0000'.
Try comparing it to \0 or \u0000 instead of null.