CODEWITHSUNDEEP
java
Rick Bunch
Rick Bunch

Reputation: 31

Java scanner: nextInt

I am a beginner in programming (learning Java). I am trying to write a program in which I list four different options for the user to choose from.

Here is part of it:

import java.util.*;
    public class fight {

            public static int upgrade1 = 0;
            public static int upgrade2 = 0;
            public static int upgrade3 = 0;
            public static int upgrade4 = 0;

    public static void main(String[] args) {

        Scanner scan = new Scanner(System.in);

        System.out.println("Please enter your name:");

            String player = scan.next();    

System.out.println("You have earned 2 upgrade points. Which of the following traits would you like to boost by 2 points?\n"
    + " 1. upgrade1\n 2. upgrade2\n 3. upgrade3\n"
    + " 4. upgrade4");

                    if (scan.nextInt() == 1) {
                        upgrade1 = upgrade1 + 2;
                            System.out.println("Your upgrade1 level is now: " + upgrade1);
                    }
                    else if (scan.nextInt() == 2) {
                        upgrade2 = upgrade2 + 2;
                            System.out.println("Your upgrade2 level is now: " + upgrade2);
                    }
                    else if (scan.nextInt() == 3) {
                        upgrade3 = upgrade3 + 2;
                            System.out.println("Your upgrade3 level is now: " + upgrade3);
                    }
                    else if (scan.nextInt() == 4) {
                        upgrade4 = upgrade4 + 2;
                            System.out.println("Your upgrade4 level is now: " + upgrade4);
                    }                                                       
        }
}

The problem is: When the user enters which option they want to pick, they must enter the number (x being the number they choose) x amount of times. For instance, the user wants to choose option 3. They must enter the number 3 three times into the console before it understands and completes the next line.

Here is the console after running the program:

Please enter your name: rick Hello, rick. You have earned 2 upgrade points. Which of the following traits would you like to boost by 2 points? 1. upgrade1 2. upgrade2 3. upgrade3 4. upgrade4 3 3 3 Your upgrade3 level is now: 2

I hope this makes sense, and any help is much appreciated (I assume I'm just making a dumb rookie error). Also, if you have any constructive criticism about the way it's structured, please don't hesitate. Thanks!

Upvotes: 2

Views: 9671

Answers (4)

Sean James
Sean James

Reputation: 330

This is because you are calling scan.nextInt() in every if/else if statement. What you want to do is store the value they entered and then check the value in the if/else if statements, otherwise you're basically prompting the user for input multiple times.

int input = scan.nextInt();

if (input == 1) {
    upgrade1 = upgrade1 + 2;
        System.out.println("Your upgrade1 level is now: " + upgrade1);
}
else if (input == 2) {
    upgrade2 = upgrade2 + 2;
        System.out.println("Your upgrade2 level is now: " + upgrade2);
}
else if (input == 3) {
    upgrade3 = upgrade3 + 2;
        System.out.println("Your upgrade3 level is now: " + upgrade3);
}
else if (input == 4) {
    upgrade4 = upgrade4 + 2;
        System.out.println("Your upgrade4 level is now: " + upgrade4);
}

Upvotes: 0

paulsm4
paulsm4

Reputation: 121649

You can't repeatedly call scan.nextInt(). Unless, of course, you're expecting multiple different integers to be read.

Instead:

Scanner scan = new Scanner(System.in);
System.out.println("Please enter your name:");
String player = scan.next();
int ichoice = scan.nextInt();
switch (ichoice) {
  case 1:
  ...

Upvotes: 2

Wug
Wug

Reputation: 13196

Each time you call scan.nextInt in one of your if statements, it reads another int. Change to:

int userChoice = scan.nextInt();
if (userChoice == 1)
{
    ...
}
else if (userChoice == 2)

...

As for constructive criticism, pick a style you like and use it. Your indentation is all over the place; this makes code more difficult to read. It doesn't matter if it's a commonly used style and it doesn't matter what everyone else thinks of it, just make sure you like it and stick to it.

Eclipse can auto-format code for you, and this behavior is customizable (You can fiddle with it so it matches your style).

Upvotes: 1

2v0mjdrl
2v0mjdrl

Reputation: 575

Each time you call nextInt(), another int is read from the input. You thus want to call it only once!

int choice = scan.nextInt();

if (choice == 1) ...
if (choice == 2) ...

Upvotes: 0

Related Questions