Multi Class program

Hi I was attempting to create a calculator that can add subtract multiply and divide to challenge myself but find myself getting stuck around the switch part:(I will point out the errors within the switch message that say "The method addition etc(String[]) in the type addition etc is not applicable for t开发者_开发百科he arguments ()." I believe the problem lies within the public void of the other classes.

Script:

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);

    }
}

note: I'm using eclipse so each class is on like a different page.

Your methods expect the argument "args", which you don't use. Remove it. For example:

public void Addition(String Args[]) {

becomes:

public void Addition() {

(by the way, your code does not follow Oracle Java Naming Convention)

While the acute problem is that you need to change your method signatures to not have any parameters or change the method invocation to send a parameter, I think there is a better solution you should concider.

Change the methods in your operation classes to be constructors:

public class Addition { 
    public Addition() {
    //...
    }
}

Then you do not need to instantiate all the operations for each run and the switch becomes:

switch(mode) {
case 1:
    Addition();
    break;
case 2:
    Subtraction();
    break;
case 3:
    Multiplication();
    break;
case 4:
    Division();
    break;
default:
    System.out.println("You have not selected a mode, do so by editing the mode variable in the source.");
}

Do not have any parameter (in this program, the String[] args parameter) for the function inside the four operator classes. Your program should work without them.

public class Addition { 
    public Addition() {
    //...
    }
}

Same applies for other classes too.

public class Subtraction { 
    public Subtraction() {
    //...
    }
}

public class Multiplication{ 
    public Multiplication() {
    //...
    }
}

public class Division { 
    public Division() {
    //...
    }
}