整除 javascript 整除计算器

如题

import java.util.Scanner;

public class Calculator {
    public static void main(String[] args) {
        System.out.println("只支持整数计算，并且一次输入一个字符！");
        Scanner scanner1 = new Scanner(System.in);
        System.out.println("请输入第一个数字：");
        int a=scanner1.nextInt();
        Scanner scanner2 = new Scanner(System.in);
        System.out.println("请输入第二个数字：");
        int b=scanner2.nextInt();
        Scanner scanner = new Scanner(System.in);
        System.out.println("请输入运算方式，即加减乘除+-*/：");
        String c=scanner.next();
        switch (c){
            case "+":
                System.out.println("运算结果："+(a+b));
                break;
            case "-":
                System.out.println("运算结果："+(a-b));
                break;
            case "*":
                System.out.println("运算结果："+(a*b));
                break;
            case "/":
                System.out.println("运算结果："+(a/(double)b));
                break;
            default:
                System.out.println("输入方式错误！");
        }
        scanner1.close();
        scanner2.close();
        scanner.close();
    }

}

将int改为double即可支持小数，但是输入整数得带小数点，就这样吧，等后面学了怎么进行数据校检再说吧