[Java:S3398] False, if method touches members from other class

[mfroehlich (Marvin Fröhlich)]

A little hard to describe in one row for subject. But here we go.

public class A
{
    private int counter = 0;
    
    private void foo() // FP
    {
        counter++;
    }
    
    public class B
    {
        public void bar()
        {
            foo();
        }
    }
}

In this example rule S3398 in SonarQube will suggest to move foo() into B, because foo() is used from nowhere, but from a method in B. So far, so good.

Now as we see, foo() manipulates a member of A and hence belongs very well to A. I would consider it, well not right, but also not wrong, to move foo() into B. At least I would not want this rule to complain, as it is a matter of taste.

What do you think?