How can I format a number adding corresponding suffix to the end of it? - Java

Question

I need in my text view to add a number, but also I need to add the corresponding suffix to that number like 1 is 1st, 2 is 2nd and so on. Is there any way to do this instead of writing a bunch of switch statements? The number is dynamic, so it doesn't have a range. Thank you.

Detailed description:

public String getNumberWithSuffix(int number) {
    /** Add an suffix to the end of the number, convert to string and return. 
        E.g. the number is 1, the suffix needs to be 'st', 
        so we concat them and return 1st. 
        If the number is 2, the suffix needs to be 'nd', 
        we concat them and return 2nd. 
        The range is not specified so it can be any integer number. 
    **/
}

your question is a vague description of an assignment, nothing more. — Stultuske, Feb 15 '22 at 09:37
I can write this using switch statement, but I wondering maybe there's something that Java provides and we can use that to do so. — Hayk Mkrtchyan, Feb 15 '22 at 09:38
I think he means the additional letters like "st" to 1, "rd" to 3 etc — Avital, Feb 15 '22 at 09:41
So you don't have to write switch cases for all numbers, just check for the last digit of the passed number. If last digit is 1 then append "st", if 2 then append "nd"and if 3 then append "rd" and th otherwise (last else case) — Astha Garg, Feb 15 '22 at 09:49
@AsthaGarg actually I thought about it, but the thing is that for 11 the last number is also 1, but suffix is 'th'. 11th. In other cases seems it works. — Hayk Mkrtchyan, Feb 15 '22 at 09:52
Ya correct, so what I understand is for such exceptions you need to check them at starting. I don't see any in-built way in java so you need to handle manually. Basically 1 is exception not 11, 21 kind of numbers here — Astha Garg, Feb 15 '22 at 09:54
If you are asking what can replace a switch statement, I'd suggest a map. If you are asking if there is a library that already handles this, I dont know of one. — leoOrion, Feb 15 '22 at 09:57

score 2 · Answer 1 · answered Feb 15 '22 at 10:23

Found an answer from similar question:-

public static String ordinal(int i) {
    String[] suffixes = new String[] { "th", "st", "nd", "rd", "th", "th", "th", "th", "th", "th" };
    switch (i % 100) {
    case 11:
    case 12:
    case 13:
        return i + "th";
    default:
        return i + suffixes[i % 10];

    }
}

Link - https://stackoverflow.com/a/6810409/8762338

leoOrion · Answer 2 · 2022-02-15T10:36:43.073

Something like this -

// Initialize this as a singelton smwhere.
Map<Integer, String> suffixMapper = new HashMap<Integer, String>
suffixMapper.put(1, 'st');
suffixMapper.put(2, 'nd');
suffixMapper.put(3, 'rd');

String getSuffix(int num) {
  if (num % 100 / 10 == 1) return "th"
  Integer lastDigit = num % 10
  String suffix = suffixMapper.get(lastDigit) != null ? suffixMapper.get(lastDigit) : "th";
  return suffix;
}

You can also make the map return an Optional to handle the null if needed.

If you are using Android, you can check this answer out - https://stackoverflow.com/a/49384322/4983469

How can I format a number adding corresponding suffix to the end of it? - Java

2 Answers2