Java TicTacToe Check for Win

public boolean checkwin(char c)
    {

        int left, right, up, down;
        boolean leftwin = false, rightwin = false, upwin = false, downwin = false, dI = false, dIV = false; //named my diagonals off the quadrants I is upperright, II is upperleft etc.
        for (int row = 0; row < size; row++)
        {
            for (int col = 0; col < size; col++)
            {
                if (board[row][col] == c)
                {
                    leftwin = true;
                    rightwin = true;
                    upwin = true;
                    downwin = true;// dI = true; dII = true; dIII = true; dIV = true;
                    left = col - 1;
                    while (left >= 0)
                    {
                        if (this.board[row][left] != c)
                        {
                            leftwin = false;
                            break;
                        }
                        left--;
                    }
                    right = col + 1;
                    while (right < size)
                    {
                        if (this.board[row][right] != c)
                        {
                            rightwin = false;
                            break;
                        }
                        right++;
                    }
                    up = row - 1;
                    while (up >= 0)
                    {
                        if (this.board[up][col] != c)
                        {
                            upwin = false;
                            break;
                        }
                        up--;
                    }
                    down = row + 1;
                    while (down < size)
                    {
                        if (this.board[down][col] != c)
                        {
                            downwin = false;
                            break;
                        }
                        down++;
                    }
                    //Diagonal statements
                    if ((col == 0 && (row == 0 || row == size - 1)))
                    {
                        dI = false;
                        dIV = false;
                        up = row - 1;
                        right = col + 1;
                        while (up >= 0 && right < size)
                        {
                            dI = true;
                            if (this.board[up][right] != c)
                            {
                                dI = false;
                                break;
                            }
                            up--;
                            right++;
                        }
                        down = row + 1;
                        right = col + 1;
                        while (down < size && row < size)
                        {
                            dIV = true;
                            if (this.board[down][right] != c)
                            {
                                dIV = false;
                                break;
                            }
                            down++;
                            right++;
                        }

                    }
                }
                if ((downwin && upwin) || (leftwin && rightwin) || (dI) || (dIV))
                {
                    return true;
                }
            }
        }



        return false;
    }