java - 多类类(class)

Question

嗨，我正在尝试创建一个可以加减乘除的计算器来挑战自己，但发现自己卡在开关部分:(我会指出开关消息中的错误，即“方法加法等(字符串 [] ) 中的类型添加等不适用于参数 ()。”我相信问题出在其他类的公共(public)无效中。

脚本:

public class ComputronCalc {
    public static void main(String args[]) {

        int mode;
        mode = 1;

        Addition ADD = new Addition();
        Subtraction SUB = new Subtraction();
        Multiplication MUL = new Multiplication();
        Division DIV = new Division();

        System.out.println("Hello welcome to the Computron fully functional calculator, coded by Samuel Cole, designed by Dwight Schrute.");

        switch(mode) {
        case 1:
            ADD.Addition();<-----------addition is underlined in red
            break;
        case 2:
            SUB.Subtraction();<-------------same
            break;
        case 3:
            MUL.Multiplication();<---------------same
            break;
        case 4:
            DIV.Division();<----------------same
            break;
        default:
            System.out.println("You have not selected a mode, do so by editing the mode variable in the source.");
        }
    System.out.println("Thank you for choosing Computron.");
    }
}

import java.util.Scanner;

public class Addition {
    public void Addition(String Args[]) {
        Scanner input = new Scanner(System.in);

        double fnum, snum, answer;
        System.out.println("Type the first number you desire to calculate.");
        fnum = input.nextDouble();
        System.out.println("Type the second number you desire to calculate.");
        snum = input.nextDouble();
        System.out.println("Calculating...");
        answer = fnum + snum;
        System.out.println(answer);

    }
}

import java.util.Scanner;

public class Multiplication {
    public void Multiplication(String Args[]) {
        Scanner input = new Scanner(System.in);

        double fnum, snum, answer;
        System.out.println("Type the first number you desire to calculate.");
        fnum = input.nextDouble();
        System.out.println("Type the second number you desire to calculate.");
        snum = input.nextDouble();
        System.out.println("Calculating...");
        answer = fnum * snum;
        System.out.println(answer);

    }
}

import java.util.Scanner;

public class Division {
    public void Division(String Args[]) {
        Scanner input = new Scanner(System.in);

        double fnum, snum, answer;
        System.out.println("Type the first number you desire to calculate.");
        fnum = input.nextDouble();
        System.out.println("Type the second number you desire to calculate.");
        snum = input.nextDouble();
        System.out.println("Calculating...");
        answer = fnum / snum;
        System.out.println(answer);

    }
}

注意:我使用的是 eclipse，所以每个类都像不同的页面一样。

Answer 1

您的方法需要您不使用的参数“args”。去掉它。例如:

public void Addition(String Args[]) {

变成:

public void Addition() {

(顺便说一句，您的代码不遵循 Oracle Java Naming Convention )