Thread: Hi, your may be seeing alot of me soon ;)

Hi guys,

I'm new at Java, but I'm new and learning fast. I brought a book of Amazon called 'Java for Dummies' by Barry Burd, I recommend this book, it is easy to read and well explained. I am willing to learn alot about Java, hoping to be able to orientate myself to Android application development. I speak english and french fluently, though I don't think french will help alot here
I have written very little thing so far in Java, including a simple calculator (no gui) and a couple of other various thing. I'm new to all this, but I'm motivated.
The first thing I'm gonna ask is:
-Is this good for my first code ever in Java?

import static java.lang.System.in;
import static java.lang.System.out;
import java.util.Scanner;
 
public class calculatorCore {
 
	public static void main(String[] args) {
		Scanner input = new Scanner(in);
		boolean realAnswerMenu = false;
 
		out.println("------ extremeCalc by " + info.creatorName + "------");
		out.println();
		out.println("Menu-------------------------------");
		out.println("-- 1 - Calculate now! -------------");
		out.println("-- 2 - Info -----------------------");
		out.println("-----------------------------------");
		out.println();
		do {
			out.print("MENU > ");
			String menu = input.next();
			try {
				int menuInt = Integer.parseInt(menu);
				out.println();
				switch (menuInt) {
					case 1:
						realAnswerMenu = true;
						break;
					case 2:
						out.println("Simple, just type what your asked, and press [ENTER], if you want to stop, when they ask you a sign type stop and fill the input spaces with random ints until it stops, uppercase or lowercase does not matter.");
						out.println("Made by " + info.creatorName);
						out.println("Build " + info.build + " "+ info.versionName);
						out.println();
						break;
					default:
						out.println("Sorry, dunno that option, enter a number depending what you want and press [ENTER]");
						out.println();
				}
			} catch (NumberFormatException e) {
				out.println();
				out.println("Sorry, dunno that option, enter a number depending what you want and press [ENTER]");
				out.println();
			}
		} while (realAnswerMenu == false);
		out.println();
		String sign;
		double num;
		out.print("NUM  > ");
		double tot = input.nextDouble();
		boolean stop = false;
 
		do {
			do {
				out.print("SIGN > ");
				sign = input.next();
				if (!sign.equalsIgnoreCase("stop") && !sign.equals("-") && !sign.equals("+") && !sign.equals("*") && !sign.equals("/")) {
					out.println("ERROR> Sign not recognised");
				}
				if (sign.equalsIgnoreCase("stop")) {
					stop = true;
				}
			} while (!sign.equalsIgnoreCase("stop") && !sign.equals("-") && !sign.equals("+") && !sign.equals("*") && !sign.equals("/"));
			out.print("NUM  > ");
 
			num = input.nextDouble();
			if (sign.equals("+")) {
				tot = calculations.addition(tot , num);
			}
			if (sign.equals("-")) {
				tot = calculations.subtraction(tot , num);
			}
			if (sign.equals("*")) {
				tot = calculations.multiplication(tot , num);
			}
			if (sign.equals("/")) {
				tot = calculations.division(tot , num);
			}
			out.println("TOTAL> " + tot);
		} while (stop != true);
		out.print("Thanks HF for using my calculator :D, " + info.creatorName);
	}
 
}

public class calculations {
 
	public static double addition(double tot , double num) {
		return tot += num;
	}
	public static double subtraction(double tot , double num) {
		return tot -= num;
	}
	public static double multiplication(double tot , double num) {
		return tot *= num;
	}
	public static double division(double tot , double num) {
		return tot /= num;
	}
 
}

public class info {
 
	static int build = 1;
	static String versionName = "0.1 ALPHA";
	static String creatorName = "zeokila";
 
}

Please give me tips to make it better.

OK, thanks, and sorry for posting in the wrong section :S

the question about the structure is about OO. Anyway, the code looks great for a first timer, try to start organizing what you want done in groups.
I think your calc class should probably just be a method. and your info class could also be a method (perhaps one that printed out the version info).

methods DO STUFF to things
classes MAKE THINGS

I agree with what JonLane said, you can just make your calculations class into methods. I dont think there is any use in having it be a class; you can probably make it a void method too.

like for example:

public static void  add(double tot, double dum)
{
     tot = tot + num;
     System.out.print("TOTAL: " + tot);
}