Tic-Tac-Toe Game Result

/*
 * Problem : Find the result.
 * Input   : 3 lines of 3 characters.
 * Output  : The result text.
 * Approach: Check 8 lines.
 * Time    : O(1)
 * Space   : O(1)
 * Java    : 8 or newer.
 */
import java.util.Scanner;

public class Main {
    // This method solves the task. It receives the input and returns the answer.
    static String solve(String[] lines) {
        // Step 1: Collect all 8 winning lines: 3 rows, 3 columns and 2 diagonals. Each line is a text of 3 characters.
        String[] winLines = new String[8];
        for (int i = 0; i < 3; i++) {
            winLines[i] = lines[i];
            winLines[3 + i] = "" + lines[0].charAt(i) + lines[1].charAt(i) + lines[2].charAt(i);
        }
        winLines[6] = "" + lines[0].charAt(0) + lines[1].charAt(1) + lines[2].charAt(2);
        winLines[7] = "" + lines[0].charAt(2) + lines[1].charAt(1) + lines[2].charAt(0);

        // Step 2: A player wins if one line has the same player three times.
        for (String line : winLines) {
            if (line.equals("XXX")) {
                return "X wins";
            }
            if (line.equals("OOO")) {
                return "O wins";
            }
        }

        // Step 3: No winner. If an empty cell is left, the game goes on. Otherwise it is a draw.
        for (String row : lines) {
            if (row.indexOf('.') >= 0) {
                return "Pending";
            }
        }
        return "Draw";
    }

    public static void main(String[] args) {
        Scanner scanner = new Scanner(System.in);
        java.util.List<String> all = new java.util.ArrayList<>();
        while (scanner.hasNextLine()) {
            String line = scanner.nextLine().trim();
            if (!line.isEmpty()) {
                all.add(line);
            }
        }
        String[] lines = all.toArray(new String[0]);
        System.out.println(solve(lines));
    }
}