Modify numeric data type to set its minimum to 1

Question

I want to have a numeric data type starting at 1. Not use negative and 0.

So I could use Example class

public class Example extends Long {

    private int min = 1;

    public LifeTime(long value) {
        this.value = value;
    }

How could I change the min value of Long class with 1 at this Example data type class?

Is it possible to modify Long by extending the class?

Could you give a complete example? What exactly are you trying to achieve? — Mureinik, Mar 27 '20 at 12:24
It is not possible to extend `Long`, it is declared as `final` — Amongalen, Mar 27 '20 at 12:27
I have a field where the user could type there Long. However, I do not want to allow the user to type 0. I do not have regex condition otherwise I might do it like that. However, I want to limit the Long.class so that the user could only type from 1 to max of Long. — SeriousEngineer, Mar 27 '20 at 12:27
Yes I saw it as an error @Amongalen how is it possible to modify it somehow? — SeriousEngineer, Mar 27 '20 at 12:27
Usually, you do not solve such a "trivial" limitation of valid input values with an extra class. Instead, use a _Validator_ to achieve your goal. — Florian Albrecht, Mar 27 '20 at 12:30

score 2 · Answer 1 · answered Mar 27 '20 at 12:29

You could just use the constructor as a way to add the validation. E.g.:

public class LifeTime {

private static final int MINIMAL_VALUE = 1;
private long value;

public LifeTime(long value) {
    if (value < MINIMAL_VALUE) {
        this.value = MINIMAL_VALUE;
    } else {
        this.value = value;
    }
}

Modify numeric data type to set its minimum to 1

1 Answers1