Test-Driven Java Development, Second Edition - Second Edition

Requirement 6 – win condition (II)

The first win condition.

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

The checkWinCondition private method implements this rule by scanning whether or not the last move is a winning one:

... 
private Color winner;

public static final int DISCS_FOR_WIN = 4;
 
public void putDisc(int column) {
  ...
  if (numOfDiscs < ROWS) {
    board[column - 1][numOfDiscs] = currentPlayer;
    printBoard();
    checkWinCondition(column - 1, numOfDiscs);
    switchPlayer();
    ...
}
 
private void checkWinCondition(int col, int row) {
  Pattern winPattern = Pattern.compile(".*" + currentPlayer + "{" + DISCS_FOR_WIN + "}.*"); // Vertical check StringJoiner stringJoiner ...