Should ProtectedMethodInFinalClass really exist?

[victornoel]

When implementing a final class that extends an abstract class with protected methods, it feels very wrong to me to mark the implementations of those methods as being public.

But with the rule ProtectedMethodInFinalClassCheck, I am forced to make them public.
This exposes undesired internal behaviour to the outside and thus seem a bad idea.

[0crat]

@krzyk/z please, pay attention to this issue

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@victornoel/z this project will fix the problem faster if you donate a few dollars to it; just click here and pay via Stripe, it's very fast, convenient and appreciated; thanks a lot!

[krzyk]

@victornoel why would you use protected in such class? Doesn't default also work for the cases that you need?
protected adds only gives subclasses visibility (which is pointless in final class) in comparison to the default scope:

[victornoel]

@krzyk see the following example:

public abstract class AbstractClass {
    protected abstract void method();
}

// here qulice complains with ProtectedMethodInFinalClassCheck
public final class FinalClass extends AbstractClass {
    @Override
    protected void method() {
        // implem
    }
}

// here javac complains with "Cannot reduce the visibility of the inherited method from AbstractClass"
public final class FinalClass extends AbstractClass {
    @Override
    void method() {
        // implem
    }
}

// here we made a method not meant to be exposed public
public final class FinalClass extends AbstractClass {
    @Override
    public void method() {
        // implem
    }
}

To answer you question: default does not work in that case, so I have to make it public, which I think is worst design than having a protected method in a final class (or it should only be for non-overridden methods).

[krzyk]

@victornoel Oh, in that case it should be excluded in case of @Override

[krzyk]

@0crat in

[krzyk]

@0crat assign me

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@0crat in (here)

@krzyk Job #901 is now in scope, role is DEV

[0crat]

@0crat assign me (here)

@krzyk The job #901 assigned to @krzyk/z, here is why; the budget is 30 minutes, see §4; please, read §8 and §9; if the task is not clear, read this and this; there will be no monetary reward for this job

[0crat]

Bug was reported, see §29: +15 point(s) just awarded to @victornoel/z

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Manual assignment of issues is discouraged, see §19: -5 point(s) just awarded to @krzyk/z

[krzyk]

@victornoel fixed in #915, it will be available with next qulice release. Please close this issue.

[victornoel]

@krzyk don't you think the rule should be stricter and only allow it in case there is an override AND the superclass method is protected?

[krzyk]

@victornoel but this will be quite a narrow case when someone widens the scope from default to protected, and it has to be in a class that has visibility of that default method (so in the same package). Please create a new bug for this (we will probably need to convert this to PMD check in that case).

[victornoel]

@krzyk yep, I understand, this issue is fixed anyway :)

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Job was finished in 3 hours, bonus for fast delivery is possible (see §36)

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Order was finished: +35 point(s) just awarded to @krzyk/z

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The job #901 is now out of scope