Test-Driven Java Development, Second Edition - Second Edition

Requirement 7 – win condition (III)

This is the same win condition, but in a different direction.

If a player inserts a disc and connects more than three discs of his color in a straight horizontal line, then that player wins.

A few lines to implement this rule are as follows:

...
private void checkWinCondition(int col, int row) {
  ...
  // Horizontal check
  stringJoiner = new StringJoiner("");
  for (int column = 0; column < COLUMNS; ++column) {
    stringJoiner.add(board[column][row].toString());
  }
  if (winPattern.matcher(stringJoiner.toString()).matches()) { 
    winner = currentPlayer;
    System.out.println(currentPlayer + " wins");
    return;
  }
  ...
}
...