Java

Welcome to Dream.In.Code
	Become a Java Expert! Join 306,831 Java Programmers for FREE! Get instant access to thousands of Java experts, tutorials, code snippets, and more! There are 1,742 people online right now. Registration is fast and FREE... Join Now! Chat LIVE With a Java Expert

Write a CalculatorClass using the ScannerClass and a SwitchStatement

Write a CalculatorClass using the ScannerClass and a SwitchStatement, Have to write a Calculator which calculate the 5 fundamental rules of

Options

p.tryfle	17 May, 2009 - 04:50 AM Post #1
New D.I.C Head Joined: 17 May, 2009 Posts: 4	Hallo to everybody, I'm a noob to java and have to write this calculator. I'm learning JAVA for three weeks now but this is a number to big for me. Sitting three days of thinking, reading, searching and of course trying to get it right I'm out of any ideas! Most of the programm code have to be in methods and the main method should just start the programm! My version works until the system asks you about the arithmetic operation. I got no Idea how to link the switch statement including the arithmetic operations to the scannermethod. So that one choose an arithmetic operation and the result comes out like this: for example systemoutput: 12+12=24. The task is to realize this using local variables as much as possible. here is the code: CODE import java.util.Scanner; public class calculator { private int calculate; private int x; private int y; private int result; public static void input(){ Scanner sc = new Scanner(System.in); System.out.print("Systemoutput: "); System.out.print("insert an integral number:"); System.out.println(""); int x = Integer.parseInt(sc.next()); System.out.print("userinput: "); System.out.println(x); System.out.println(""); System.out.print("Systeoutput: "); System.out.print("insert another integral number:"); System.out.println(""); int y = Integer.parseInt(sc.next()); System.out.print("userinput: "); System.out.println(y); System.out.println(""); System.out.print("Systemoutput: "); System.out.println("please choose the arithmetic operation"); System.out.println(" (" + 1 + " = " + "addition; " + 2 + " = " + "subtraction;" + 3 + " = "); System.out.print(" multiplication; " + 4 + " = " + "division; " + 5 + " = " + "percent; )" ); int calculate = Integer.parseInt(sc.next()); } public static void calculate(){ public int getcalculate(){ switch (calculate) { case 1 : result = x + y; break; case 2: result = x - y; break; case 3: result = x * y; break; case 4: result = x / y; break; case 5: result = x * 100 / y; break; } } } public static void main (String[] args){ input(); calculate(); } } Maybe somebody can help. Thanks in advance. greets
	This Post Was Helpful!

Register for Free to Make These Ads Go Away!

g00se

RE: Write A CalculatorClass Using The ScannerClass And A SwitchStatement

17 May, 2009 - 05:55 AM

Post #2

D.I.C Lover

Joined: 19 Sep, 2008
Posts: 1,234

Thanked: 144 times
My Contributions

You're not far off. Inegrate something like the following into it:

java


System.out.println("please choose the arithmetic operation (+ - / *)");
char operator = sc.next().charAt(0);
System.out.println(calculate(x, y, operator));


....

public int calculate(int x, int y, char operator) {
// Assume integer only operations
	switch(operator) {
		case '+':
			return x + y;
		case '-':
			return x - y;
		case '/':
			return x / y;
		case '*':
			return x * y;	
		default:
			throw new IllegalArgumentException(String.format("%s is not a valid operator", operator));
}

This Post Was Helpful!

p.tryfle	RE: Write A CalculatorClass Using The ScannerClass And A SwitchStatement 17 May, 2009 - 07:20 AM Post #3
New D.I.C Head Joined: 17 May, 2009 Posts: 4	QUOTE(g00se @ 17 May, 2009 - 05:55 AM) You're not far off. Inegrate something like the following into it: java System.out.println("please choose the arithmetic operation (+ - / )"); char operator = sc.next().charAt(0); System.out.println(calculate(x, y, operator)); .... public int calculate(int x, int y, char operator) { // Assume integer only operations switch(operator) { case '+': return x + y; case '-': return x - y; case '/': return x / y; case '': return x * y; default: throw new IllegalArgumentException(String.format("%s is not a valid operator", operator)); } thanks, this helps but I have to put all the basic arithmetiic operations into it. In addition the results of the "/" and percent: " x * 100 / y" have to put out in double! I have changed the code: please excuse the german language, because I'm running out of time I can't rewrite it anymore. CODE import java.util.Scanner; public class TaschenRechner { public static void eingabe(){ Scanner sc = new Scanner(System.in); int zahl1,zahl2,ergebnis; float ergebnis1; System.out.print("Systemausgabe: "); System.out.print("Bitte geben Sie einen ganzzahligen Wert ein:"); System.out.println(""); zahl1 = sc.nextInt(); System.out.print("usereingabe: "); System.out.println(zahl1); System.out.println(""); System.out.print("Systemausgabe: "); System.out.print("Bitte geben Sie einen weiteren ganzzahligen Wert ein:"); System.out.println(""); zahl2 = sc.nextInt(); System.out.print("usereingabe: "); System.out.println(zahl2); System.out.println(""); System.out.print("Systemausgabe: "); System.out.println("Bitte geben Sie die gewünschte Operation an"); System.out.println(" (" + 1 + " = " + "Addieren; " + 2 + " = " + "Subtraktion;" + 3 + " = "); System.out.print(" Multiplikation; " + 4 + " = " + "Division; " + 5 + " = " + "Prozent; )" ); ergebnis = sc.nextInt(); System.out.print("usereingabe: "); System.out.println(ergebnis); System.out.println(""); System.out.print("Systemausgabe: "); switch (ergebnis) { case 1 : System.out.print(zahl1 + " + " + zahl2); System.out.print (" = " ); System.out.print(ergebnis = zahl1 + zahl2); break; case 2: System.out.print(zahl1 + " - " + zahl2); System.out.print (" = " ); System.out.print(ergebnis = zahl1 - zahl2); break; case 3: System.out.print(zahl1 + " * " + zahl2); System.out.print (" = " ); System.out.print(ergebnis = zahl1 * zahl2); break; case 4: // Here the result should be put out in double not in integer System.out.print(zahl1 + " / " + zahl2); System.out.print (" = " ); System.out.print(ergebnis = zahl1 / zahl2); break; case 5: // Here the result should be put out in double not in integer System.out.print(zahl1 + " * 100 / " + zahl2); System.out.print (" = " ); System.out.print(ergebnis= zahl1 * 100 / zahl2); break; } } public static void main (String[] args){ eingabe(); } }
	This Post Was Helpful!

g00se	RE: Write A CalculatorClass Using The ScannerClass And A SwitchStatement 17 May, 2009 - 07:34 AM Post #4
D.I.C Lover Joined: 19 Sep, 2008 Posts: 1,234 Thanked: 144 times My Contributions	QUOTE but I have to put all the basic arithmetiic operations into it. I don't understand sorry. The basic operations are in the code i gave you, with the exception of percent. As for needing to return double, just change the return type of the 'calculate' method
	This Post Was Helpful!