Java 代码未按计划运行

Question

这不是完整的代码，只是问题区域。 (完整代码如下)

if (passLength > 4) {
    System.out.println("Signup alost complete.");

    Random rand = new Random();

    int randm = rand.nextInt(100000) + 1;

    System.out.println(
            "To confirm you are not a robot, please enter this code: "
                    + randm);

    String code = userInput.next();

    if (code.equals(randm)) {
        System.out.println("Thank you, " + userName);
        System.out.println(
                "You may now login. Begin by entering your username");

        if (userInput.equals(userName)) {
            System.out.println("Now please enter you password");
        }

        // Where the rest of the program will go
    }

    else {
        System.out.println("The code entered is incorrect.");
    }

}

else {
    System.out.println("Invalid Password");
}

我正在制作一个程序，用户创建一个帐户，然后再登录。我遇到问题的部分是验证以确保用户是人(他们显然是，但仍然是)。创建他们的用户名和密码后，我生成并打印一个随机 int，他们必须输入它。

我的问题是程序总是跳到 else 语句，并打印 "The code entered is incorrect." 即使我输入得很完美。

谁能告诉我我做错了什么？

下面是完整的代码，以防万一。

public static void main(String[] args) {

    System.out.println("Hi! To begin please choose your username.");
    System.out.println("To do this, please enter your username below. ");
    System.out.println("This name must be at least three characters.");

    Scanner userInput = new Scanner(System.in);

    String userName = userInput.next();

    int nameLength = userName.length();

    if (nameLength > 2) {

        System.out.println("Now please enter your password.");
        System.out
                .println("This password must be at lease five characters");

        String passWord = userInput.next();

        int passLength = passWord.length();

        if (passLength > 4) {
            System.out.println("Signup alost complete.");

            Random rand = new Random();

            int randm = rand.nextInt(100000) + 1;

            System.out.println(
                    "To confirm you are not a robot, please enter this code: "
                            + randm);

            String code = userInput.next();

            if (code.equals(randm)) {
                System.out.println("Thank you, " + userName);
                System.out.println(
                        "You may now login. Begin by entering your username");

                if (userInput.equals(userName)) {
                    System.out.println("Now please enter you password");
                }

                // Where the rest of the program will go
            }

            else {
                System.out.println("The code entered is incorrect.");
            }

        }

        else {
            System.out.println("Invalid Password");
        }

    }

    else {
        System.out.println("Invalid Username");

    }

}

Answer 1

你正在比较一个字符串和一个整数，这显然是不一样的。

int randm = rand.nextInt(100000) + 1;
...
String code = userInput.next();
if  (code.equals(randm)) 

要解决此问题，您可以将整数转换为字符串并比较字符串(或其他方式)。

String randm = String.valueOfrand.nextInt(100000) + 1;
...
String code = userInput.next();
if  (code.equals(randm)) // Comparing string now

编辑:正如@Pshemo 指出的那样，int code = userInput.nextInt();将完成工作，因为您将整数与 == 进行比较.