java - 当我期望代码简单地打印 "Error"时，为什么我的代码会抛出 ArithmeticException ？

Question

我编写了一个程序，要求用户输入两个数字，如果第二个数字是 0，它应该会给出错误。但是，我收到了一个错误，如下所示。我有一个 if-else 语句，但它没有按照我的预期进行。我不确定我做错了什么。

public static void main(String[] args) {
    int x, y;
    Scanner kbd = new Scanner(System.in);

    System.out.print("Enter a: ");
    x = kbd.nextInt();
    System.out.print("Enter b: ");
    y = kbd.nextInt();

    int result = add(x, y);
    int result2 = sub(x, y);
    int result3 = multi(x, y);
    int result4 = divide(x, y);
    int result5 = mod(x, y);

    System.out.println(x + " + " + y + " = " + result);
    System.out.println(x + " - " + y + " = " + result2);
    System.out.println(x + " * " + y + " = " + result3);
    System.out.println(x + " / " + y + " = " + result4);
    System.out.print(x + " % " + y + " = " + result5);
}

public static int add(int x, int y) {
    int result;
    result = x + y;
    return result;
}

public static int sub(int x, int y) {
    int result2;
    result2 = x - y;
    return result2;
}

public static int multi(int x, int y) {
    int result3;
    result3 = x * y;
    return result3;
}

public static int divide(int x, int y) {
    int result4;
    result4 = x / y;
    if (y == 0) {
        System.out.print("Error");
    } else {
        result4 = x / y; 
    }
    return result4; 
}

public static int mod(int x, int y) {
    int result5;
    result5 = x % y;
    if (y == 0) {
        System.out.print("Error");
    } else {
        result5 = x % y;
    }
    return result5;
}

输出 我收到此错误..

Enter a: 10
Enter b: 0
Exception in thread "main" java.lang.ArithmeticException: / by zero

Answer 1

你得到这个是因为当你除以 0 时，Java 会抛出异常。如果您只想使用 if 语句来处理它，请使用如下内容:

public static int divide(int x, int y){
   int result;
   if ( y == 0 ) {
 // handle your Exception here
 } else {
   result = x/y; 
  }
  return result; 
}

Java 还通过 try/catch block 处理异常，它运行 try block 中的代码，并在 catch block 中处理异常的处理方式。所以你可以这样做:

try {  
       result4 = divide(a, b);
}
catch(//the exception types you want to catch ){
     // how you choose to handle it
}