从字符串输入中声明变量（Java）

Question

When I previously asked a question, it got many downvotes because I was not very specific. I will do my best to be clear this time. I have read questions with similar titles, but none have made it clear to me.

Basically, I have been assigned to make a fractional calculator for my AP comp sci class. The first checkpoint for this assignment is to be able to read fractions inputted by the user without the code crashing. For example, "1_1/2" "1/2" or just 1.

So far, I've gotten the following -

public static void identify() {
        Scanner console = new Scanner(System.in);
        String fraction = console.next();

        if(fraction.contains("_")) {
            int wholenumber = console.nextInt();
            int numerator = console.nextInt();
            int denomenator = console.nextInt();
            System.out.print(wholenumber + "_" + numerator + "/" + denomenator);
        }
        else if(fraction.contains("/")) {
            int numerator = console.nextInt();
            int denomenator = console.nextInt();
            System.out.print(numerator + "/" + denomenator);

        } 
        else {                                                                          
            System.out.print(fraction);
        }

        }

I thought it was working at first, but then I realized that if I inputted 1_1/2 or 1/2, the code would wait for inputs for the numerator, denominator, and whole number. So my problem is that I want the previously mentioned values to be declared from the originally inputted string, and not from different inputs.

I understand this might be confusing to read, so basically I if input 1_1/2, I want my code to declare 1 as wholenumber, 1 as numerator, and 2 as denominator. How would I achieve this?

Answer 1

int[] numbers = Arrays.asList(fraction.split("_|/")).stream()
            .mapToInt(s -> Integer.parseInt(s))
            .toArray();

Then,
If entry is of type 1_1/2 :

• wholenumber = numbers[0]
• numerator = numbers[1]
• denomenator = numbers[2]

If entry is of type 1/2 :

• numerator = numbers[0]
• denomenator = numbers[1]