Java是一种广泛使用的编程语言，具有高效性和跨平台性。这里介绍Java如何输入算数运算符和两个运算数的代码。

import java.util.Scanner;public class ArithmeticOperators {public static void main(String[] args) {Scanner input = new Scanner(System.in);System.out.print("请输入一个算数运算符 (+, -, *, /): ");String operator = input.next();System.out.print("请输入第一个运算数: ");double num1 = input.nextDouble();System.out.print("请输入第二个运算数: ");double num2 = input.nextDouble();if (operator.equals("+")) {double sum = num1 + num2;System.out.println(num1 + " " + operator + " " + num2 + " = " + sum);} else if (operator.equals("-")) {double difference = num1 - num2;System.out.println(num1 + " " + operator + " " + num2 + " = " + difference);} else if (operator.equals("*")) {double product = num1 * num2;System.out.println(num1 + " " + operator + " " + num2 + " = " + product);} else if (operator.equals("/")) {if (num2 == 0) {System.out.println("除数不能为0！");} else {double quotient = num1 / num2;System.out.println(num1 + " " + operator + " " + num2 + " = " + quotient);}} else {System.out.println("无效的算数运算符！");}}}

以上代码使用Scanner类从用户输入获取算数运算符和两个运算数，然后根据不同的运算符进行相应的运算，并输出结果。如果除数为0，则会显示“除数不能为0！”提示。此代码可用于Java的基础学习。