写一个简易计算器用java

好的，下面是一个简单的计算器 Java 代码，可以实现加减乘除四则运算：

import java.util.Scanner;

public class Calculator {
    public static void main(String[] args) {
        double num1, num2;
        Scanner scanner = new Scanner(System.in);
        System.out.print("输入第一个数字: ");
        num1 = scanner.nextDouble();
        System.out.print("输入第二个数字: ");
        num2 = scanner.nextDouble();

        System.out.print("请选择运算符 (+, -, *, /): ");
        char operator = scanner.next().charAt(0);

        double result;
        switch(operator) {
            case '+':
                result = num1 + num2;
                System.out.print(num1 + " + " + num2 + " = " + result);
                break;
            case '-':
                result = num1 - num2;
                System.out.print(num1 + " - " + num2 + " = " + result);
                break;
            case '*':
                result = num1 * num2;
                System.out.print(num1 + " * " + num2 + " = " + result);
                break;
            case '/':
                result = num1 / num2;
                System.out.print(num1 + " / " + num2 + " = " + result);
                break;

            default:
                System.out.println("错误! 请输入正确的运算符");
                return;
        }
    }
}

如果您有任何其他问题，请告诉我。