Java错误处理-这是最好的方法吗？

我正在制作的控制台程序中有一个错误，我似乎无法处理错误

如果用户输入了不正确的输入类型（例如整数所在的浮点），则会对其进行谴责，并且程序会运行（即使程序关闭，也会按我的方式运行）：

例如，如果用户输入一个不等于零的变量零（由于零的除法），用户将受到谴责，生活仍在继续，程序仍在运行：

while (b == 0) {
            System.out.println("Did you even read the instructions??  You cannot divide by zero!");
            System.out.println();
            System.out.println("Second Integer: ");
            b = scanner.nextLong();
        }

但是，如果用户试图除以零，然后输入错误的输入类型，程序将崩溃。我做错了什么？我尝试过像在其他实例中一样进入try/catch-while循环，但似乎没有达到目的：

System.out.println("Second Integer: ");
        while(!scanner.hasNextLong()){
            System.out.println("You entered something bad..  Why do you hurt me?");
            System.out.println("*Calcumatastic dies, and I hope you feel remorseful*");
            try {
                Thread.sleep(4000);
            } catch (InterruptedException f) {
                f.printStackTrace();
            }
            System.exit(0);
        }
        b = scanner.nextLong();
        while (b == 0) {
            System.out.println("Did you even read the instructions??  You cannot divide by zero!");
            System.out.println();
            System.out.println("Second Integer: ");
            b = scanner.nextLong();
        }

---

如果您尝试执行零除法，则会抛出一个

java.lang.arithmetricException

，当您尝试读取一个long，并且用户输入了一些无法解析的内容时，会抛出

InputMismatchException

（可能称为“崩溃”）

发生错误，因为您正在使用

b=scanner.nextLong（）当用户输入0而不检查用户是否输入了有效的长值时

以下是您的代码：

public static void main(String[] args) {
    Scanner scanner = new Scanner(System.in);

    long b = 0;

    do {
        System.out.println("Second Integer: ");

        b = readLong(scanner);

        if (b == 0) {
            System.out.println("Did you even read the instructions??  You cannot divide by zero!");
            System.out.println();
        }
    } while (b == 0);
}

private static long readLong(Scanner scanner) {
    if (!scanner.hasNextLong()) {
        System.out.println("You entered something bad..  Why do you hurt me?");
        System.out.println("*Calcumatastic dies, and I hope you feel remorseful*");
        try {
            Thread.sleep(4000);
        } catch (InterruptedException f) {
            f.printStackTrace();
        }
        System.exit(0);
    }
    return scanner.nextLong();
}

您的问题是您的输入验证似乎是连续的。也就是说，检查无效输入，然后检查零值。您可能希望在每次有输入时都执行这两项操作

您可能希望在单个循环中检查所有错误情况。比如：

System.out.println("Second Integer: ");
// a loop wrapping your other validation checks
while(scanner.hasNext()){ // while there is input:
    while(!scanner.hasNextLong()){ // check for non-long input
        System.out.println("You entered something bad..  Why do you hurt me?");
        System.out.println("*Calcumatastic dies, and I hope you feel remorseful*");
        try {
            Thread.sleep(4000);
        } catch (InterruptedException f) {
            f.printStackTrace();
        }
        System.exit(0);
    }
    b = scanner.nextLong();
    while (b == 0) { // check for non-zero input
        System.out.println("Did you even read the instructions??  You cannot divide by zero!");
        System.out.println();
        System.out.println("Second Integer: ");
        b = scanner.nextLong();
    }
}

“撞车”是什么意思？您是否得到异常和堆栈跟踪？正确，InputMismatchException被抛出，不是崩溃。抱歉术语上的错误，我有点糊涂。谢谢你的帮助！没问题。我们是来帮忙的。别忘了对答案投赞成票或反对票。
System.out.println("Second Integer: ");
// a loop wrapping your other validation checks
while(scanner.hasNext()){ // while there is input:
    while(!scanner.hasNextLong()){ // check for non-long input
        System.out.println("You entered something bad..  Why do you hurt me?");
        System.out.println("*Calcumatastic dies, and I hope you feel remorseful*");
        try {
            Thread.sleep(4000);
        } catch (InterruptedException f) {
            f.printStackTrace();
        }
        System.exit(0);
    }
    b = scanner.nextLong();
    while (b == 0) { // check for non-zero input
        System.out.println("Did you even read the instructions??  You cannot divide by zero!");
        System.out.println();
        System.out.println("Second Integer: ");
        b = scanner.nextLong();
    }
}