How can I display a variable when the user asks for it?

Question

Basically, I want the user to input 'Average' or 'Sum' so I can then display the relevant one that was requested using System.out.println();

But how can I do this? (Apologies if this is really simple)

int SumChocolates = 0;
SumChocolates = (int) (data [0][7] + data [1][7] + data [2][7] + data [3][7]);

int AvgChocolates = 0;
AvgChocolates = (int) (SumChocolates / 4);

http://www.mkyong.com/java/how-to-read-input-from-console-java/ — Pshemo, Jan 15 '15 at 15:01
Take the input with a scanner, and have a switch-case statement for the input provided. — Drew Kennedy, Jan 15 '15 at 15:01
[tag:eclipse] tag removed as the question has no bearing on this IDE. — Hovercraft Full Of Eels, Jan 15 '15 at 15:02
@Pshemo You can't use console input in Eclipse. (The question was originally tagged Eclipse) — mbomb007, Jan 15 '15 at 15:03
@mbomb007 Examples of this article are about reading from standard input stream of process (`System.in`), regardless if process was run with console (`java.exe`) or without console (`javaw.exe` like eclipse does). — Pshemo, Jan 15 '15 at 15:04

score 1 · Answer 1 · answered Jan 15 '15 at 15:04

You can use a Scanner then use Scanner.nextLine(); to get input from the user in the console.

Also, you may want to take a look at the standard naming schemas in Java

Scanner scan = new Scanner(System. in ); //Create a new Scanner
System.out.println("Would you like the average, or sum?");
String input = scan.nextLine(); //Get input from the user

int SumChocolates = 0; //Must declare out here, because Average case uses this
SumChocolates = (int)(data[0][7] + data[1][7] + data[2][7] + data[3][7]);

if (input.equalsIgnoreCase("Sum")) {
    System.out.println("The Sum is: " + SumChocolates);
} else if (input.equalsIgnoreCase("Average")) {
    int AvgChocolates = 0;
    AvgChocolates = (int)(SumChocolates / 4);
    System.out.println("The average is: " + AvgChocolates);
}

score 0 · Answer 2 · answered Jan 15 '15 at 15:02

0

You can use a Scanner:

Scanner scanner = new Scanner(System.in);
String userInput = scanner.next();

answered Jan 15 '15 at 15:02

Michał Szydłowski

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better use `scanner.nextLine()` – Sharky Jan 15 '15 at 15:09
Out of curiosity: why exactly? next() returns the next token entered by the user as String. – Michał Szydłowski Jan 15 '15 at 15:10
1

what if the user enter more than one token? – Sharky Jan 15 '15 at 15:13

mbomb007 · Answer 3 · 2015-01-15T15:19:18.250

0

Use a scanner. Depending on their input, display the output you want. Also, variables should be lowerCamelCase to comply with Java coding standards.

This checks to make sure they enter valid input before displaying a result.

Scanner s = new Scanner(System.in);
String input = "";
System.out.println("Would you like to see the Average, or the Sum?");

while (true) {
    input = s.nextLine();
    if (input.equalsIgnoreCase("Average")) {
        System.out.println(avgChocolates);
        break;
    } else if (input.equalsIgnoreCase("Sum")) {
        System.out.println(sumChocolates);
        break;
    } else {
        System.out.println("Invalid input. Please enter 'Average' or 'Sum'.");
    }
}

edited Jan 15 '15 at 15:19

answered Jan 15 '15 at 15:06

mbomb007

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`if (input == "Average")` [no No NO, not again](http://stackoverflow.com/questions/513832/how-do-i-compare-strings-in-java). – Pshemo Jan 15 '15 at 15:07
you can't compare strings by "==" - use input.equals("Average") – Sharky Jan 15 '15 at 15:08
Oh sorry. I've been programming in other languages lately. Thanks, for that. – mbomb007 Jan 15 '15 at 15:08

How can I display a variable when the user asks for it?

3 Answers3