Java：向while循环添加用户输入

Question

我试图在PlayerOne类中放入一个while循环，这样就可以通过用户输入来选择玩家的职业。我不知道怎么让它起作用。你能给我一个建议或提示吗？谢谢！（我想你不需要玩家类或者主类，所以我就让他们置身事外）

Scanner scanner = new Scanner(System.in);
while (true) {
         System.out.println("Choose your profession: \n" +
        "Press 1 for a knight class\n" +
        "Press 2 for a rider class\n" +
        "Press 3 for a mage class");
    int choice = scanner.nextInt();
    scanner.nextLine();
    switch (choice) {
        case 0:
            // here I want to put an option to choose a knight by pressing number 1
            break;
        case 1:
            // an option to choose a rider by pressing number 2
            break;
case 1:
            // an option to choose a mage by pressing number 3
            break;

Answer 1

public static void main(String[] args) {
    Scanner scanner = new Scanner(System.in);
    String profession= null;
    while (profession == null) {
        System.out.println("Choose your profession: \n" +
                "Press 1 for a knight class\n" +
                "Press 2 for a rider class\n" +
                "Press 3 for a mage class");
        String choice = scanner.nextLine();

        if (choice.equals("1")){
            profession = "knight";
            System.out.println("You selected: "+profession+" class.");
        }else if (choice.equals("2")){
            profession = "rider";
            System.out.println("You selected: "+profession+" class.");
        }else if (choice.equals("3")){
            profession = "mage";
            System.out.println("You selected: "+profession+" class.");
        }else {
            System.out.println("invaild option");
        }
    }
    
}

Answer 2

我认为当某人选择一个有效的职业时，你需要一个停止条件，比如：

Scanner scanner = new Scanner(System.in);
String profession = null;
while (profession == null) {
    System.out.println("Choose your profession: \n" +
        "Press 1 for a knight class\n" +
        "Press 2 for a rider class\n" +
        "Press 3 for a mage class");
    int choice = scanner.nextInt();
    scanner.nextLine();
    switch (choice) {
        case 1:
            profession = "knight";
            break;
        case 2:
            profession = "rider";
            break;
        case 3:
            profession = "mage";
            break;
        default:
            System.out.println("Invalid option");
            profession = null;
            break;
    }
}
System.out.println("You selected: "+profession+" class.");