Long or String for Norwegian birth number

Question

I have a class called Person that looks something like this:

public abstract class Person {
    private String birthNo;
    ...
}

Numbers of Norwegian births are 11 digits and are constructed according to the algorithm described on this page on Wikipedia . I cannot use int since most birth numbers are greater than Integer.MAX_VALUE.

I heard that when deciding whether to use a String or integer to store numeric values, you should ask yourself: do I need to perform mathematical operations on this value?

I do this on birthNo, but many operations become somewhat easier with String charAt(int i). If I were to keep birth numbers for how long, I would have to use modulo and division to get the desired digit:

int ninth = Character.getNumericValue(birthNo.charAt(8));

against.

int ninth = birthNo / 100 % 10

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Answer 1

. . (DDMMYY), .

BirthNumber LocalDate int String , , . , .

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import java.time.LocalDate;

public class DNumberLocalDate {

    private final LocalDate localDate;
    private final boolean isDNumber;

    public DNumberLocalDate(LocalDate localDate, boolean isDNumber) {
        this.localDate = localDate;
        this.isDNumber = isDNumber;
    }

    public DNumberLocalDate(LocalDate localDate) {
        this(localDate, false);
    }

    public int getDayOfMonth() {
        return isDNumber ? localDate.getDayOfMonth() + 40 : localDate.getDayOfMonth();
    }

}

Answer 2

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BigDecimal BigInteger.

Answer 3

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