Java switch语句：优雅处理用户输入与特殊场景的策略

import java.util.Scanner;

public class TicTacToeGame {
    // 井字棋盘，使用String[][]表示，方便存储" ", "X", "O"
    String[][] board = {
        {" ", "|", " ", "|", " "},
        {"-", "-", "-", "-", "-"},
        {" ", "|", " ", "|", " "},
        {"-", "-", "-", "-", "-"},
        {" ", "|", " ", "|", " "}
    };

    int currentPlayer = 1; // 1代表玩家X，2代表玩家O
    Scanner scanner = new Scanner(System.in);

    public void startGame() {
        String inputCommand;
        while (true) { // 游戏主循环
            printBoard(); // 打印当前棋盘

            boolean moveAccepted = false;
            int targetRow = -1, targetCol = -1; // 临时存储用户选择的坐标

            while (!moveAccepted) {
                String playerPiece = (currentPlayer == 1) ? "X"龙猫"O";
                System.out.println("玩家 " + playerPiece + "，请输入您的落子位置 (例如: 1,1): ");
                inputCommand = scanner.next();

                boolean inputFormatValid = false; // 标记输入格式是否匹配某个case

                // 根据输入解析坐标
                switch (inputCommand) {
                    case "1,1" -> { targetRow = 0; targetCol = 0; inputFormatValid = true; }
                    case "1,2" -> { targetRow = 0; targetCol = 2; inputFormatValid = true; }
                    case "1,3" -> { targetRow = 0; targetCol = 4; inputFormatValid = true; }
                    case "2,1" -> { targetRow = 2; targetCol = 0; inputFormatValid = true; }
                    case "2,2" -> { targetRow = 2; targetCol = 2; inputFormatValid = true; }
                    case "2,3" -> { targetRow = 2; targetCol = 4; inputFormatValid = true; }
                    case "3,1" -> { targetRow = 4; targetCol = 0; inputFormatValid = true; }
                    case "3,2" -> { targetRow = 4; targetCol = 2; inputFormatValid = true; }
                    case "3,3" -> { targetRow = 4; targetCol = 4; inputFormatValid = true; }
                    default -> {
                        System.out.println("输入格式无效，请检查并重新输入。");
                        // inputFormatValid 保持为 false，将继续内层循环
                    }
                }

                if (inputFormatValid) {
                    // 格式有效后，进行业务逻辑检查：位置是否已被占用
                    if (!board[targetRow][targetCol].trim().isEmpty()) { // .trim()确保即使有空格也能正确判断
                        System.out.println("该位置已被占用，请选择其他空位。");
                        // moveAccepted 保持为 false，将继续内层循环
                    } else {
                        // 格式和业务逻辑都有效，接受落子
                        moveAccepted = true;
                    }
                }
            }

            // 放置棋子
            String pieceToPlace = (currentPlayer == 1) ? "X" : "O";
            board[targetRow][targetCol] = pieceToPlace;
            System.out.println(pieceToPlace + " 成功落子在 (" + ((targetRow / 2) + 1) + "," + ((targetCol / 2) + 1) + ")");

            // 检查胜负或平局（此处省略具体实现，仅为示意）
            if (checkWin(pieceToPlace)) {
                System.out.println("玩家 " + pieceToPlace + " 获胜！游戏结束。");
                break; // 退出游戏主循环
            }
            if (checkDraw()) {
                System.out.println("平局！游戏结束。");
                break; // 退出游戏主循环
            }

            // 切换玩家
            currentPlayer = (currentPlayer == 1) ? 2 : 1;
        }
        scanner.close();
    }

    // 打印棋盘
    private void printBoard() {
        System.out.println("\n--- 当前棋盘 ---");
        for (int r = 0; r < 5; r++) {
            for (int c = 0; c < 5; c++) {
                System.out.print(board[r][c]);
            }
            System.out.println();
        }
        System.out.println("-----------------\n");
    }

    // 检查胜利条件（简化示例，实际游戏需完整实现）
    private boolean checkWin(String player) {
        // 检查行
        for (int r = 0; r < 5; r += 2) {
            if (board[r][0].equals(player) && board[r][2].equals(player) && board[r][4].equals(player)) {
                return true;
            }
        }
        // 检查列
        for (int c = 0; c < 5; c += 2) {
            if (board[0][c].equals(player) && board[2][c].equals(player) && board[4][c].equals(player)) {
                return true;
            }
        }
        // 检查对角线
        if (board[0][0].equals(player) && board[2][2].equals(player) && board[4][4].equals(player)) {
            return true;
        }
        if (board[0][4].equals(player) && board[2][2].equals(player) && board[4][0].equals(player)) {
            return true;
        }
        return false;
    }

    // 检查平局条件（简化示例，实际游戏需完整实现）
    private boolean checkDraw() {
        for (int r = 0; r < 5; r += 2) {
            for (int c = 0; c < 5; c += 2) {
                if (board[r][c].trim().isEmpty()) {
                    return false; // 仍有空位，未平局
                }
            }
        }
        return true; // 所有位置都已填满
    }

    public static void main(String[] args) {
        new TicTacToeGame().startGame();
    }
}