Question

Do we really need static final constants in Java?

Assume I have the following code:

public class Test {

    public static final int A = 1234;

    public static int getA()
    {
        return 1234;
    }
}

Can you please compare the following two cases in terms of efficiency?

1. Test.A

2. Test.getA()

Answer 1

Assuming a JIT compiler, there should be no noticeable difference in efficiency – at least not enough to make a significant difference in the execution speed of your application.

There is a noticeable gain in flexibility, though: encapsulating the value in a method is nearly always good, because it lets you change the way the value is calculate later.

A notable exception to this rule is pure constants, say, from the world of mathematics: it does not make much sense to encapsulate access to Math.PI, because there is no chance that the value of this fundamental constant is going to change, prompting a need to switch the method the value is obtained in your program.