提供测试包的私有方法？

Question

I'm writing the following class:

public class MyClass{

    private final MyAnotherClass[][] anotherClasses;

    public MyClass(//args){
        //initialization
    }

    //...
}

I'd like to test this class, but wouldn't like to provide any methods exposing its iternal state ( anotherClasses array in this case). The test is going to test the state of the array, so we have to access it.

Is it considering as a good practice to provide a method, say

MyAnotherClass[][] getAnotherClasses(){
    retun anotherClasses;
}

with package-private visibility to use it only for testing? I'm kind of not sure about that. We introduce some annoying coupling between the class and its test...

Maybe there's a better approach to deal with that?

Answer 1

As already mentioned, it is not good practice to test non-public methods. But sometimes if it is really needed for me, I'm using @VisibleForTesting annotation from guava.