Increment the number part of a String but keeping the character part in Java

I came across several questions but without an answer for my problem.

I have a code camming from data-base in this format: FR000009.

The output should be: FR000010

String original = "FR000009";
    String incremented = "FR" +  String.format("%0" + (original.length() - 2) + "d",
            Integer.parseInt(original.substring(2)) + 1);
    System.out.println(incremented);

Here came the difference from other questions: I want to parse the string without the need of hardcoding FR like in the example above. In time there can be different country codes (DE, UK,RO etc).

>Solution :

You can use this code by stripping all digits first and then stripping all non-digits:

String original = "FR000009";

String repl = String.format("%s%0" + (original.length() - 2) + "d",
    original.replaceFirst("\\d+", ""),
   (Integer.valueOf(original.replaceFirst("\\D+", "")) + 1));
//=> "FR000010"

Here:

• replaceFirst("\\d+", ""): removes all digits from input, giving us FR
• replaceFirst("\\D+", ""): removes all non-digits from input, giving us 000009

Note that if there are always only 2 letters at the start and remaining are digits then you won’t even need a regex code, just use substring:

String repl = String.format("%s%0" + (original.length() - 2) + "d",
   original.substring(0, 2),
   (Integer.valueOf(original.substring(2)) + 1));