Help making a very simple calculator?

[sfs]

Hi, I'm very new to java I have been self teaching for about 3 days now and at the moment I am attempting to create a very simple calculator, however I have encountered a problem.

I'll show the code I've done first though:

 import java.util.Scanner;

public class calculatortest{

   enum mathfunctions { Sum, Difference, Product, Quotient }

              public static void main(String [] args){

Scanner input = new Scanner ( System.in );

   mathfunctions a;
   mathfunctions b;
   mathfunctions c;
   mathfunctions d;

   String f;

   double x;
   double y;
   double z;


 a = mathfunctions.Sum;
 b = mathfunctions.Difference;
 c = mathfunctions.Product;
 d = mathfunctions.Quotient;

   System.out.print("Choose a mathematical function: Sum, Difference, 

Product, Quotient?");
   
f = input.nextmathfunctions(); // This is where the error is occuring.

if(f.equals(a)){

System.out.print("Enter a value for x?");

x = input.nextDouble();

System.out.print("Enter a value for y?");

y = input.nextDouble();

z = x + y;

System.out.print("The sum of the two values is: " + z );
}

else if (f.equals(b)){

System.out.print("Enter a value for x?");

x = input.nextDouble();

System.out.print("Enter a value for y?");

y = input.nextDouble();

z = x - y;

System.out.print("The difference of the two values is: " + z );
}

else if(f.equals(c)){

System.out.print("Enter a value for x?");

x = input.nextDouble();

System.out.print("Enter a value for y?");

y = input.nextDouble();

z = x * y;

System.out.print("The product of the two values is: " + z );
}

else if(f.equals(d)){

System.out.print("Enter a value for x?");

x = input.nextDouble();

System.out.print("Enter a value for y?");

y = input.nextDouble();

z = x / y;

System.out.print("The quotient of the two values is: " + z );
}
}
}

The error I get is:

 calculatortest.java:30: error: cannot find symbol
f = input.mathfunctions();
symbol:   nextmathfunctions()
location:  variable input of type scanner

Can anyone help explain the problem for me?

[Fubarable]

You can't make up methods for a class (i.e., you're calling a nextmathfunctions() method on a Scanner object) and expect them to mathemagically work. Check out the Scanner API to see what methods are available to it, and only use those methods.

[sfs]

I realised I was making things way more complicated then they needed to be, so I got rid of the enums and worked it out. It's all working fine now thanks.