try...catch異常捕獲

1. 這是沒用catch修補程式碼

        package com.catches;

        import java.util.Scanner;

        public class Demo01 {
            //需求：輸入兩數，求兩數的商
            public static void main(String[] args) {
                Scanner sc = new Scanner(System.in);
                System.out.println("請輸入第一個整數：");
                 //判斷錄入的數是否整數

                 if (sc.hasNextInt()){
                   int num1 = sc.nextInt();
                   if(num1!=0){
                       System.out.println("請輸入第二個整數：");
                       if (sc.hasNextInt()){
                           int num2 = sc.nextInt();
                           if (num2!=0){
                               System.out.println("商："+num1/num2);
                           }else {
                               System.out.println("輸入為0的數");
                           }

                       }else {
                           System.out.println("輸入不是整數");
                       }
                   }else {
                       System.out.println("輸入為0的數");
                   }

                 }else {
                     System.out.println("輸入不是整數");
                 }


            }
        }

 

2. 使用異常處理

        package com.catches;

        import java.util.Scanner;

        public class Demo02 {
            public static void main(String[] args) {
                try{Scanner sc = new Scanner(System.in);
                    System.out.println("別懷疑，輸入兩個數：");
                int num1 = sc.nextInt();
                int num2 = sc.nextInt();
                System.out.println("輸入兩個數的商是："+num1/num2);
            }catch(Exception ex){
                    System.out.println("輸入資料有誤");
                }
            }
        }